Water can also be blamed for causing units to fail, we understand the need for some of these engines to be pressure washed but you have to consider the problems it can cause. Then check for continuity to ground on all four injector ground wires. Can any one help. I am curious as to why you suggest cleaning my MAP sensor and other sensors on the engine. If the ECU is suspected as a bad part, you need to use a scan tool such as a VAG com to attempt to communicate with the ECU. Remote shifters also running at $2000 and Shifters at $1000. crank senser fault or main engine ground on intake have had 3or 4 bad crank senser latly no spark or meatal bitts have found the magnet on end of crank senser or broken timing belt. Baseball Baseball: Facebook Baseball: Twitter Baseball: Instagram Baseball: Tickets Baseball: Schedule Baseball: Roster Baseball: News Basketball Basketball: Facebook Basketball: Twitter Basketball: Instagram Basketball: Schedule Basketball: Roster Basketball: News Cross Country Cross Country: Facebook Cross Country: Twitter Cross Country: Instagram Cross. The bad earth/ground can be traced to an essential ground strap on the front upper transmission bolt. Almost seems like there has to be a loose connection somewhere. ---- I will look into the power sources for these items. Fill out the Repair and Return Form and send us your unit today. People said i could have a loose wire/connector or a bad ground. 88 Likes, 6 Comments - Daniel Lux (@lux. such as a simple bad sensor. The engine control unit is a computer and a highly advanced piece of technology. Took out the ECU and opened it up but found no signs of it being shorted or anything open. Engine hesitation during acceleration: a bad throttle position sensor will make very hard for the ECU incrementing the necessary amount of fuel during sudden acceleration. The code chart is very short for this code, it says, If you have code P0606 go to step A. crank senser fault or main engine ground on intake have had 3or 4 bad crank senser latly no spark or meatal bitts have found the magnet on end of crank senser or broken timing belt. ECM works on other motor. In my honda book it says code 0= bad ecu. It could either be because the positive signal is not getting sent or the ground is bad on the stick coil. At this point you understand the ECU found in the middle of the engine bay. 5 volts of battery voltage. Checking the Fuel Pump relay, I find that the trigger from the computer is only giving 5. Dedicated to all things from Mopar, Chrysler, Dodge, Plymouth, and Desoto. Step A says to replace ECM. The original ground comes from two engine grounding points located at the topside of the upper intake manifold. So if you have dumb coils, you connect the coil to the 12V and the other end goes in to the ECU, and if the ecu decided it needs to be fired, closes the circuit to the ground. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. A bad oil leak is an instigator; oil will find its way into the ECM and slowly eat up its circuits. A bad ECU ground can cause every type of running problem the car can have. Re: 92 s10 Bad ECM? Dangerous to rely on wire colors since it is all too easy to splice in a wire of a different color, that is why i actually put in the pins on the plug. The ecm/pcm is a reman. Volkswagen Jetta Difficult to Diagnose Electrical Issues Are Typically Due to Ground Issues - 195 reports. Check all electrical connections. Check spark plugs. Fill out the Repair and Return Form and send us your unit today. Easy to use parts catalog. No ground at #9 pin on ECM. I talked with some motorcycle repair shops and a guy suggested that it is a bad ECU. The terms ECM and PCM are often used interchangeably when referring to engine electronics, but there is a difference. Control the bad plays with a young quarterback and let him go out and play and play his game. Known good ECM doesn't work on this motor and fuel pump doesn't run at key on. I could not have known at the time that inviting the ECU staff archaeologist and two fel-low students to join me would be the best decision I made all year. This website's security and privacy policies may differ from that of ECU's website and we cannot guarantee the accuracy of the information found on this third-party website. My fuel Pump and ECU have both been suggested. He says it was a bad ground for the "pcm ecu under the distributor" The only big ground I see is frame to frame. If not, check the wiring diagram to find where the wire is grounded. ) Poor ECM to engine block ground. At Module Experts, we are able to both repair and remanufacture ECMs, but we always strive to repair your existing ECM whenever possible, to keep your cost and wait. It is the central control unit of most vehicles and controls a variety of functions, such as electrical system power distribution, emissions, ignition, and fuel systems. If you are testing a vehicle for this code check the routing of the spark plug wires making sure they are not to close to the EST circuit(s) wiring. This is not happening. I have swapped injectors from cylinder to cylinder prob stayed a cylinder #3. Why start with the ground system? If the ground connections in the engine compartment are bad, you can chase problems across a variety of vehicle systems for hours and still not properly diagnose the root cause. the intelligent power distribution module (ipdm) assembly contains an engine control module (ecm) relay that has a diode for electrical current noise reduction. It looks like it's under 31/7, and the second attachment shows it's near the drivers side by the frame. vodka, Mar 17, 2017 #10. I'm trying to figure out if I have a bad ecu. Cadillac CTS SRX 3. Some manufacturers employ a dedicated O2 sensor ground. If this were to occur, excessive heat could cause a fire, possibly resulting in severe injury or death. Note: The installer of this harness is responsible for all ground wires not provided with this part. The injectors (3, 4, 5, 6, 8, 10, 12, or 16 of them) are operated by individual transistors inside the ECU that control the ground side. Even when I do Wide band hook ups the ground is directly on the head. JMU outgained ECU 228-to-114, had 13 first downs compared to ECU’s seven and won the turnover battle 1-to-0. Only the FL-XiED, current ViED and AFXiED have the ground wire for these bikes. I think I can help. Bad MAF harness Ground- Nissan Official Fix It could also be some sort of an internal ECU ground and for some reason it doesn't work sometimes so the harness just. That will severely affect the car's performance. On 5 V circuits, such as those used by the ECM to sense and control the engine and transmission, disconnect the ECM and the battery, set the multimeter to measure continuity, and probe between the circuit and body ground or engine ground. Ecm Performance offers custom Engine Control Module (ECM) programming & Diesel Particulate Filter (DPF) Solutions for Cummins ISB 6. It grounds through its case to the chassis just like the ignition ECU module needs a solid ground. •Determine if the source (battery +) or ground side of that section of the circuit is bad by the following: - Check for available voltage on the source side. The ignition module and the EEC-IV are not so likely. Im referring to the solution of the following thread. Im not throwing a CEL so I dont think anything is damaged but is it too late to reset the ecu or has there already been damaged done?. ACM Sensor Supply 2 Short to Ground: Sensor supply voltage 2 Voltage Below Normal, Or Shorted To Low Source; short circuit to ground on sensor supply 2 ECU 3510. Does anyone know the symptoms of an ECM that losses its memory? Does it behave as if the ECM is just bad? The strangest thing is the lack of a check engine light with the key turned on. There are no stored ECM faults, ignition and run switches are fine. After this, the flow chart recommends I replace the ECU. The metal plate behind the drivers seat is normally grounded with one or two black wires with ring terminals (can't remember how many is stock). I have swapped injectors from cylinder to cylinder prob stayed a cylinder #3. Ford Modules is a leader of automotive engine control units, known as ECU, ECM, PCM, TCU, we remanufacturer heavy truck, diesel truck ecu, FICM. I thought these things never fail especially at only 103,500 miles! Called the local Honda dealership they're telling me $1,550 to replace. Not that bad ECM's are uncommon in this carline but this ECM had been given the famous "tap test," by yours truly, often over the past three weeks. I took it into the local dealership and they said the ECM is bad and I need a new one to the tune of $800. Can any one help. A Chevrolet's ECM can sense problems as they present themselves, and it keeps an ongoing record. Ecu Transit. The icing on the cake is that the sprag starter clutch has completely gone, press the starter and it just freewheels and doesn't turn over the. - Check for continuity to ground on the ground side. The engine isn't turning over to start up. The ECU is usually diagnosed by a process of elimination. I am working on 2005 srx Cadillac with a 3. The injectors (3, 4, 5, 6, 8, 10, 12, or 16 of them) are operated by individual transistors inside the ECU that control the ground side. Check spark plugs. You are leaving Eastman Credit Union's website and visiting a third-party website. Faulty Engine Control Module (ECM) Engine Control Module (ECM) harness power supply circuit is open or shorted Engine Control Module (ECM) harness ground supply circuit is open or shorted. I check for power on the maf and I'm getting power and 3 ground. The only connection to a battery post negative should be to another battery negative, the vehicle chassis, and/or the engine block. Since it is a dedicated ground, it passes through the computer on its way to the computer main power ground that terminates at the battery pigtail ground. How to I know If I Have a MPEM or ECU Failure? ground near solenoid. In other words, our main ground for all the ECM's was bad. Anyone had an ECM fail? One note I did install a VCM Muzzler II onto the vehicle about 3-4 months ago. Bad ground causing ECU reset? I have sent the ECU back to be checked, but would like to also double check all the ground points while I'm waiting for the ECU. I looked, but could not find a diagram or process for checking the ground points on our cars. Notice at the bottom they reference the ground distribution schematics. My injectors are not firing, so Ive done some testsTL;DR: Has my ECU gone bad?Tested at the ECU harness, and each injector connection reads the proper voltage when grounded. If pin 22 circuit is shorted to ground internally,that would cause the fuel pump to run continuously. Created : 980818 Last updated: 990326 This page is in general how I get to the ECU either to replace it, or to use it to run diagnostic tests on the car. It's a turbo Truck I've been tuning myself. Bad TPS Ground Voltage Drop testing sensor grounds. Does this sound like an ECM failure, and what woudl cause it? started it the BCM is probably bad. The analysis above demonstrates that no matter where you ground, there is risk of voltage rise at the ECU. It's used to regulate many systems and subsystems in your car's engine, drive train and. 3- If ECM pin connectors show damage or corrosion, make necessary repairs. Most consumers do not know this and unfortunately they spend between $2000. him being an actual mechanic and me a regular joe, he said to try the distributor, i replaced that and plug wires, but it didnt help, he said the next thing i should check is ground wires, well i found a bunch of random wires dangling by the. Another issue that can cause failure in the ECM is poor grounding. They will do what you said above. Issue is the 12v is not being switched to ground by the ECU. EFI" on the diagram below. My understanding is that the ECM takes the signal from the A/C thermostat, processes it, and sends out a ground signal on the red/blue wire. In that case, it has taken a shortcut to ground, thus creating an electrical short circuit. (See page IG-11) Repair or replace. The 2009/2010 Touring bikes require a ground wire from the XiED's. wire) from the negative battery terminal to the chassis (frame). Their flatrate express service guarantees the ECU by 3 P. Bad Power and Ground Connections You've connected the power and ground and they are not switching to allow power to the engine. A proper functioning ECU is key to the performance, reliability, and longevity of your. Stored in the main memory chip (PROM) is the software (values programmed by GM or your custom tuner) that tell the computer, among other things, how much fuel and spark to deliver to the engine for a given set of operating conditions. The body ground was not too much better, BTW. Possible, but highly unlikely. Suzuki's have a weak wire gauge feeding the ECU and the shorted fuel pump, likes to make the ECU reset over and over, click ,click ,click. • Connect a ground strap or cable (minimum of a 0 Ga. If this ground is poor, then all manner of weirdness can result including the infamous 3800 RPM hesitation. I have replaced the battery and cable ends and left the battery disconnected for 30 minutes hoping the ECM might reset itself, but that would just be too inexpensive and easy. I did a cursory search yesterday looking for frayed or broken wires, lose grounds, etc. 4 ECU ECU Fuel Pump Control Circuit Repair Repairing Your Own LH 2. key trapped is a common symptom of the bad ecm (the last code you listed might have caused it) we've had a couple cars with keys that wouldn't come out and a new ecm fixed it and other forum members have reported the same. I will take a look at how it works. Common areas that cause failures are: poor grounds and powers, bad wiring, shorted solenoids/relays, or misdiagnosis by the installer. ECU - The ECU is responsible for nearly all functions on the car. Under almost all soil conditions, the use of a ground enhancement material will improve grounding effectiveness. com Welcome to DMCTalk. Honda Civic: How to Identify Your ECU. If the ground wire is loose, then the alternator won't deliver its full power to the battery, particularly at idle. The symptoms might start out being minor, but they could progressively get worse if you don’t do anything about the ground wire. The #5 ground wire is a yellow-green wire. A cold engine should read 2-4 volts, a fully warmed engine 0-2 volts. If the ECM fails completely, it will leave the vehicle without engine management control, and will not start or run as a result. yeah this is not an ECM issue, you have a main power wire issue, or ground issue somewhere probably no power to ECM due to a burnt link or fuse or bad connection check all red wires at the alt for hot all the time fuseable links at starter solenoid. Chevrolet vehicles manufactured before 1996 use an internal computer called an Electronic Control Module, and it oversees the automated engine diagnostic routines. you say the ECU is not taking the circuit to ground? Did you have 12v at the 86 pin of relay, which is the hot side of the relay coil that the ECU takes to ground? You could just wire the FP relay to ignition by grounding pin 3 (85) The relay will energize when ign is on. A bad ground. possible cure. If one of the following vehicles comes into the shop with the “Malfunction Indicator Lamp” (MIL) “ON” and one or more of the following Diagnostic Trouble Codes (DTCs) are stored in Engine Control Module (ECM), the repair may be as simple as installing an additional ground sub-harness. Bad switches 3. Radar - Radar - Factors affecting radar performance: The performance of a radar system can be judged by the following: (1) the maximum range at which it can see a target of a specified size, (2) the accuracy of its measurement of target location in range and angle, (3) its ability to distinguish one target from another, (4) its ability to detect the desired target echo when masked by large. Disconnect the negative cable to the battery. In such a scenario, the ECU will sense the drop in engine vacuum first and then using other sensors data will decide if more fuel is required. Bending or breaking any of the legs is bad news. MIL “ON” WITH DTC U1000 OR U1010 STORED IN ENGINE CONTROL UNIT This bulletin has been amended. Reason ECU might have fried is due to the bad ground on first crank with MAP and TPS sensor reversed by accident. The ECU is located behind the glove box. If the engine does not crank wiring must be repaired between X3 pin 23 (pin 46 for CEC modules) on the engine ECM to pin 85 at the crank relay. After this, the flow chart recommends I replace the ECU. such as a simple bad sensor. Or in other words, my orignal pcm is fine and I wasted my money by partially "shotgunning" it as bad. , causing the ECM to intermittently go bad, they may not find it. On the1226870- 1227165 MAF ecm it is ecm terminal D6. I have a 87 N/A Auto, so I'm wondering if the grounds between the two ECU's are the same. I assume this means that I have a bad ground somewhere. This was definitely a problem internal to the ECM. The WTECII and WTECIII ECU's and shifter modules are expensive to replace, running between $3500. wires that feed the fuse panel and ECM, there are several, check fuses. The car suddenly developed a misfire and never recovered. Common areas that cause failures are: poor grounds and powers, bad wiring, shorted solenoids/relays, or misdiagnosis by the installer. Make Sure You Have a Quality Ground Point. measure voltage between battery and pin/wire at PCM) with engine. 2 there is a bad connection or too much resistance in the wire feeding the ECM. It's used to regulate many systems and subsystems in your car's engine, drive train and. There are 6 or 7 screws that hold the glove box in place and then you have to pull on it a little bit to release the clips. Any help is appreciated. The 5 V signal from the ECU is used in this transistor to switch the 12 V power supply to the primary coil. ---- I will look into the power sources for these items. The generic trouble code P2509 power input signal intermittent refers to an engine with an intermittent electrical signal to the Electronic Control Module (ECM) otherwise also known as a PCM or Powertrain Control Module. Repair the fault. So I'm guessin that my ecu is bad because I'm not getting a ground from the ecu. There are many reasons why you could have an faulty ECU. " Cons of a used ECU are getting the exact right one, and having it programmed to your car; pro is saving a bajillion dollars. A mechanical problem that a technician fails to recognize (or recognizes but fails to fix properly) is often blamed on the ECM. I have access to an ECM, PCM, BCM and TCM from a 2007 Sierra that I can try swapping over modules to help troubleshoot the problem if they are compatible. such as a simple bad sensor. Before you commit to spending this kind of money get a mechanic to do the diagnostic job first instead of just guessing. Prior to replacing the ECM, the installer should determine what caused the ECM to fail. Also the ECM power supply wires tend to rub and short to the battery box. Fault codes can be cleared by selecting Clear Fault Codes in the ECU Controls drop down menu. Turns out somewhere in the harness that leaves the ECU looking for a ground by the motor pull tab there must've been corrosion preventing that wire from finding ground. But, what can you do about old 2-wire nongrounding-type receptacles, where no ground exists in the outlet box?. Fault codes Chart. In the above pic, you can see some of the weirdness that can happen with previous owner stuff. Its getting 5v and ground and the signal is about 2. But that’s probably ok. Tuning a TBSS tonight, and the truck would shut down. We are the nation's premier remanufacturer & master distributor of superior quality remanufactured automotive Dodge Electronic Control units / engine control units / engine control modules / engine control computers (ECU's, ECM's, ECC's) & Power Control Modules (PCM's) and Fuel Injector Control Module (FICM) for all domestic & import vehicle applications. ECU issues/ground strap. As far as the ground is concerned on the '03, follow the battery negative cable. The story, in short version, is that my 1993 Ranger had gradually developed a problem where it would buck, and pop, and lose power. Disconnect the negative cable to the battery. One thing you can do to possibly verify that is to check the resistance to ground on the injector wire going to the ECU for the suspect injector. Coil Primary - 1. Inline fuses for the ECM power supply are common sources of issues. Ended up being a ground cable loose and corroded. I get engine management lights during cranking for TPS errors but I've checked the TPS on DucatiDiag, ScanMX5 and on a multimeter for ground, signal and power. Control the bad plays with a young quarterback and let him go out and play and play his game. Notice at the bottom they reference the ground distribution schematics. NOTE: If your existing OBD software or scanner is not returning helpful data, you may want to consider getting advanced OBD2 scanner like TOAD which will dig a lot deeper into your car's performance, health, chip data. ECU issues/ground strap. Before ordering another ECU make sure you have +12v on ECU pin 20 when key is on and pin 46 all the time or ECU will never power-up. A replacement relay costs about 10-odd Euros or about 10-odd pounds in the UK. A constant bad ground -- resulting from a frayed or damaged cable -- will create resistance in the circuit, which will deprive the headlights of power and cause them to dim. Sounded like boilerplate engineering to me. However, not all ECM motors run at variable speeds and selection depends heavily upon application specifications. Dealers and repair shops deal with these problems by what we call the shotgun approach (fixing something by replacing many things or one big thing). Our guys were seeing the scheme again after seeing it during preseason. That will severely affect the car's performance. If you ground the bumper and weld the bumper there is a parallel path for current to flow through the rest of the car which can raise the voltage across the ECU. Swap it out yourself before you spend 2k! also check those relays, fuses and maybe fuel pump. This method should only be used if all other attemts to connect to the module fail. Response time is six time worse here. Refer back to the very first plot on this page and you will see that it only took about 100ns to completely turn on. Needless to say I broke a valve spring, and just built another 5. Even when I do Wide band hook ups the ground is directly on the head. possible cure. Really wanted to bring it to all the car shows this weekend. I checked both ECC grounds and they were at 0v ref to battery with out the ecm plugged in. Remember, ANY extra air will confuse the ECU. While I had it cut I touched the ground wire back to the engine block and the solenoid switched. One thing you could try is remove the wire from the sensor and see if the needle does anything. The weird part is that it does not do this everytime I drive it. yea I have been beat on by both civilian instructors and military instructors. A cold engine should read 2-4 volts, a fully warmed engine 0-2 volts. No ICV vibration, but I can ground those two pins at ECU and get movement. Followers 1. The 5 V signal from the ECU is used in this transistor to switch the 12 V power supply to the primary coil. ECU Drops Homecoming Game to USF | Beaufort County Now East Carolina's annual homecoming game on an overcast but comfortable Saturday afternoon couldn't have started with a bigger bang, courtesy of the smallest man on the roster. A ground is a ground, I thought you were talking about how you put a positive wire from the alternator to the ground. Check for a good ground where the wire is grounded. Blower motor quits, bad relay. So the ECU isn't even completing minimal power-up. Toggling the switch simply applies or removes a ground to the ECM blue connector C1 pin-31. I have seen more issues from bad chassis grounds, than I have ever seen from going direct to battery with a ground. Bending or breaking any of the legs is bad news. Also I sent my distributor to the people I bought it from thinking that my ignitor was bad but as so as I get it back I will do the k-test. Manually fired the injectors by groundi. I'm trying to figure out if I have a bad ecu. Circuit starts at the Ing+ hot through the harness to the solenoid and back to the ecm which controls the sol. The EDU functions as the high current switching unit for actuation of the Electronic Unit Injector (EUI) solenoids. Another issue that can cause failure in the ECM is poor grounding. The 1G ECU, however, can blown the track at a couple different spots. It will most likely show a low resistance when compared to the others. Know anyone else that has one you can swap over to yours to see if that fixes the problem. EDIT: Problem was fixed, it was the ground cable. So, could the ECU have been damaged by the bad grounding, and causing all these problems, and is there anyway to check if this is the case?. ECM MODES OF OPERATION. Hi I have a 2005 Prius and had all the dash warning lights light up like a Christmas tree. My question is can a bad ecu cause a alternator to not charge? I've recently changed the connectors alternator and battery but the damn thing still wont hold a charge. If the purge solenoid is not activated, the ECM should see high voltage on the ground. Check continuity between centre contact and ECU connector pin 12. bad thermostat ground means no ecu power. A ground is a ground, I thought you were talking about how you put a positive wire from the alternator to the ground. I didnt check pin 8 the FP relay ground because I didnt have my manual and couldnt remember which pin it was. A fuel injection ECU system is an important part of a fuel injected engine because it serves several functions aside from regulating and maintaining the amount of fuel and air that the engine needs to increase horsepower. Ford Bronco EEC IV Codes. Have battery power to Cam Sensor. All communications through the CAN bus requires a good ground, continuity without shorting, lack of resistance which would cause a drop in voltage and good components. Cut wires probe connected to a known good ground) will verify continuity in the or any circuit related to an ECU, up. What you should know when using ground enhancement material. Why don't you tell us why you think it might be bad? The ECU almost never fails, but the most common problem would be "doesn't run. In an extremely important game for East Carolina University (3-5, 0-4 AAC), the Pirates, in their homecoming game, were defeated by the University of South Florida (4-4, 2-2 AAC) by a score of 45-20. The engine may still crank, but it will not be able to start without the vital inputs from the computer. A Chevrolet's ECM can sense problems as they present themselves, and it keeps an ongoing record. We can save you the time and money by testing your ECU DME before spending on costly diagnostic labor and sensors. Ford Modules is a leader of automotive engine control units, known as ECU, ECM, PCM, TCU, we remanufacturer heavy truck, diesel truck ecu, FICM. If you see the full supply voltage of 4-5 volts (the reading you should get from the ECU when the connector is pulled off the temp sensor) then the temp sensor or its ground wire are faulty. Referring to an EWD, you will notice that the throttle position sensor, water and air temperature sensors, and air flow meter all flow current to ground through circuit E2. Check out our other i-VTEC related guides here. after a 2 hour wait for a flat bed to tow it, it's sitting at the shop until tuesday. Lots of info on how to do it on this site. Basically, disconnect the ECU, and check continuity between the used OBD2 pins and the corresponding pins on the ECU side of the harness. Engine hesitation during acceleration: a bad throttle position sensor will make very hard for the ECU incrementing the necessary amount of fuel during sudden acceleration. ECU - The ECU is responsible for nearly all functions on the car. Average repair cost is $890 at 72,150 miles. Let’s start at plug A the 31 pin terminal of your Acura RSX ECU pinout. ECU is short for "electronic control unit". When conditions change, the ECM will automatically make adjustments in real time. upper control box and plug in at the ground control box to eliminate. Yes all roads lead to Rome (ECU) but we should probably do methodic testing to determine if these safety protocols are met at the starting circuit. Mercedes Common ECU Failures. Sometimes called an "executive car", the S80 was and continues to be Volvo's top-of-the-line passenger car. A replacement relay costs about 10-odd Euros or about 10-odd pounds in the UK. Without this, the ECU tends to earth/ground elsewhere, causing a specific trace to burn out on the circuit board and killing the ECU. A good way to test grounds is through a voltage drop test. A bad mass air flow sensor will make very hard for the ECU incrementing the necessary amount of fuel during sudden acceleration. thanks for everything. 9 to 1 Volts. I figure I have a bad maf b/c when I unplug it, the idling stays the same. I thought for sure I would have a bad ground but a voltage test of the 3 ground wires at the ECM showed. Same thing happened on my '88. Then use a voltmeter to check 5V on pin #3 (on ECU BLACK connector) against chassis ground. The truck actually has many ECU's. High charge rates are bad as well for the ECU. x) on Instagram: “Bad ECU ground and one aftermarket ignition coil shutting down entire spark ignition system. P0232 FORD Meaning The Engine Control Module provides ignition positive voltage to the coil side of the fuel pump relay. Incidentally, this is why many ECUs have separate ground wires for injectors vs. The symptoms of a bad ECU are the check engine light stays on, the car won't start, transmission problems, and bad emissions results. if your ecm is bad, first off the car won't start, your fuel pump won't work, no spark, basically everything shuts down Ok the above can be symptoms of a bad ECM, But that's not the only answer. I have a 2009 MRU, I'm having problems with a code that comes up (MID 128 Engine ECU, SID 232 5 volt supply, FMI 4) Inactive #19. This was definitely a problem internal to the ECM. 00 volts regulated feed line. Figured bad lead from ECM. Chevrolet vehicles manufactured before 1996 use an internal computer called an Electronic Control Module, and it oversees the automated engine diagnostic routines. The terms ECM and PCM are often used interchangeably when referring to engine electronics, but there is a difference. email [email protected] No other content has been changed. Inside ECM looks good. The 1G ECU, however, can blown the track at a couple different spots. There are 6 or 7 screws that hold the glove box in place and then you have to pull on it a little bit to release the clips. Symptoms of a bad ECU? My 1996 Jeep Grand Cherokee has been acting up the past couple months, now acting worse than before. Measure that you got 12 volts on all power supplies and verify that the ground pins at OK. Tested good, no short. Took the vehicle to the a dealer for repair and they found the coils and ECU burned out due to short in the ground wire. Ensuring proper ground across critical engine connections reduces the potential for confusion. In case the sensor is faulty, it might be intermittent. Good catch Marty. The ECM generates an initial ground pulse (FP signal at pin 22) to activate fuel pump relay when ignition key is turned on (pump prime). Again this wire usually leaves the battery box as a single wire splitting into two at the ECM. A bad ECU may actually just be a bad ground at the ECU, so be warned. When considering an ECM for application in an HVAC system, there are several factors to keep in mind. They did it for $100 bucks rather then me scratching my. x) on Instagram: “Bad ECU ground and one aftermarket ignition coil shutting down entire spark ignition system. Do you think this ECU is compatible and would it work in my car ?. Depending on what version Duramax you have, simply snip off the other wire somewhere close to the switch. Or in other words, my orignal pcm is fine and I wasted my money by partially "shotgunning" it as bad. I've seen a small handful of cars where the intake is used for a ground with using only one bolt! Will it work most likely but I know I never have to wonder that when the ground are where they are suppose to. The picture below shows the location and proper repair of a blown sensor ground trace on a 2G DSM ECU. If everything else that could cause the problem has been eliminated, but the problem still exists, it is usually the ECU. Through process of elimination you will determine if the ECU has failed. him being an actual mechanic and me a regular joe, he said to try the distributor, i replaced that and plug wires, but it didnt help, he said the next thing i should check is ground wires, well i found a bunch of random wires dangling by the. Then my red battery warning light came on. I DO have the 12V from the orange wire(pin 5), which is hot all the time from ECMb fuse. I really need to replace my battery ground cable one of these days. Again this is caused by exposure to the elements. 1990 Vanagon Camper Syncro conversion.