Bad ecm duramax. On a lly if u can not get any gauges on the insturment panel to work wiggle the blue wire connected to the ecm. This results in injector rattle and high rail pressure codes. Un hooked the batteries for hours and still no connection to the ECM. What Is an FICM? The fuel injection control module (FICM) is a component that supplies both power and What is wrong with your ECM? Tony - CLICK TO READ: FORUM RULES OR DF STAFF! My opinion is not the opinion of Duramax Forum, Vertical Scope, or other Duramax Forum staff members! Non Vendor contact information, URLs and/or links are NOT allowed in signatures OR on forum! 23 GMC Yukon 3. Mar 3, 2024 · What are the symptoms of a bad ecm? One day my truck would run great up to about 45mph the crap out on me, shake and rattle then die. Keep your ECM functioning at its best with YourMechanic. 04 lb7 allison 2wd, previous tow truck. Took to gm dealer they can’t figure it out no power to ficm. FREE LIFETIME WARRANTY & FREE SHIPPING. Find mobile mechanics near you and schedule an engine electrical inspection. The truck will only start when grounding the ECM. . Replace ECM Symptoms worsen. This is the first time this has happened to me while reading a file, the first time it happened the customer had an aftermarket radio and EFI Live lost communication with the ECM. I have done much reading on here and on google,but it is all just a guess until I know that the ecm is good or not. 0 ECM replacement issues Tags 3. Truck commands and goes full rail pressure on startup. Key on I’m seeing 2. So the dreaded cracked piston is the verdict. Problem is : truck came in a couple months back with witing rubbed on the fuel lines, happened to be the twisted pair for How much does Engine Control Module (ECM) Replacement cost? Get an estimate instantly. Learn how to Identify bad ECM symptoms with YourMechanic’s guide. ECM fuse popped. When u get the truck to fire up and it lopes very very bad take the back side The ECM has some ability to pull back the output, but doesn't have enough range to make this large of a correction. I backprobed at the ECM and found A bad ECM (Engine Control Module) in a Duramax can disable fuel injection, ignition timing, and transmission control. I paid $937 to Flagship on 1/10/22 to get a rebuilt one and supposedly will receive it late this week or early next week. Sounds like a bad ambient air temp sensor, but mine never made the truck idle high. Service, parts, cost & recommendations from YourMechanic. I'm leaning on a bad ecm but was looking for a second opinion Retried and was given the missing calibration message and ECM not found, truck would not start and the DIC was dashed out. com was founded in 2006 and created a site which houses some of the best known Duramax tech you can find. Flagship One is your trusted source for updated and pre-programmed engine control modules and module repairs. They eventually. "Battery Not Charging" message with corresponding red battery light and the system is not charging at any RPM as indicated by the dash gauge and A bad fuel pump, ignition problems, clogged fuel filter, bad mass airflow sensor, and bad crank/camshaft sensors are just a few of the problems that can cause an engine to not start. 9 when this happens I have an '05 C4500 ton and a half with 203K on it with me putting the last 3K on it. Then I didn't want to send my ECM into a company because they are like pure gold at the Well, the news went from bad to worse. I have verified that the issue is persists with multiple tune files and that it is not constant (ie it takes a few minutes for the codes ECM P0101 and ECM P0405 to come on with a Check Engine Light and "ENGINE POWER IS REDUCED" message). Just a thought, will Kory relicense the new ECM for your EFI tune, I would check with him before replacing the ECM. My next question is, where do I get a new one from, or where do I send mine in to be fixed. Here is what is going on. Get with rick fletes or Dustin smith and get one sent out. 0 diesel ecm relearn throttle Jump to Latest 5. Its getting dropped off at all in truck performance here in TX in 3 days hopefully its a simple fix Im out of element and no resources as I live in NY. Of course anything electronic could just have a bad component in it. Watching this video will help you diagnose to see if it's time to replace your engine control module. I have a 2003 Duramax. What does the ECM do, and how does it do it? The engine control module (ECM) is the computer that manages every system on the vehicle related to emissions. When I ground the case, everything works. Checked harness no blown Apr 11, 2025 · The ECM, or engine control module, is a computer that manages engine operation by using data from sensors to control components like fuel injectors and ignition coils. unbelievable really, this motor was replaced 2yrs ago and only has about 210K miles on it and ALWAYS maintained at proper intervals. He has the following 3 codes: U0073: Control Module Communication Bus Off U0100: Lost Communication with ECM/PCM U0121: Lost Communication with ABS Control Module The first time this happened it was also raining and he was driving. BenchForce explains what an ECM is, describes how it operates, and highlights what symptoms to look for when there may be a problem. Anyone ever hear of bad NOx sensors required an entire new ECU? Long story short I took my truck in at 125K for the dreaded "Poor Quality DEF" message (no CEL). Checked fuse, popped again. The LBZ FCA is a nice upgrade for faster pressure response and more top end flow. My problem was a bad cam sensor the whole time. Conclusion: Chevy Silverado Bad PCM Symptoms Does it sound like the ECM is bad to the majority of everyone on here. The tech had never seen anything like this and was amazed of ? Learn how to reset the engine control module in less than 15 minutes if you installed new parts or just for the ECM to relearn your driving habits Learn to recognize the warning signs with our guide on the symptoms of a bad ECM-power relay. 63vdc at FPR. Codes are p0642 and p0802. I just purchased a 2008 duramax with 80,000 miles on er. Poor Shifts The transmission may have a hard time shifting, or not even be able to shift at all. Always dealer serviced, so took it back to dealer. Jan 31, 2025 · 2008 Duramax LMM Having evidentual ECM issues. Checked continuity between c1 pins on ecm and fpr everything tested good but no voltage to fpr nor will the truck start. What is the part # for the ecm harness? And should I replace the ECM or harness or both? I have already taken the 3 connections apart at the ECM and cleaned them thoroughly, visualizing no bent pins I have a 2005 duramax lly throwing code p0090. The neutral safety switch I have checked also all other obvious things with no luck. It has a power connector and OBD port. Not my usual work, but for a good customer. Duramaxdiesels. The ECM is currently at a place in Grand Prarie, TX called Auto ECM. You may also notice engine performance issues, like a misfiring or a stalling engine. Attributing my chronic code / low power mode to a bad connection between the ECM and terminal. Pulled glove box door and checked wiring around ECM, no obvious signs of shorts etc. This allows you to isolate the ECM from everything else so nothing can interfere with it. ECM failures won't have anything to do with how it's being driven or really anything to do with what you are doing when it goes. Your definitive guide to Engine Control Module (ECM) Replacement. When the P0090 code is present, the truck will limp and drive somewhat "normal" but still has a reduced fuel pressure of 2000-3000psi. 5. Last week I started the dmax up it was a cold start( single digits) truck fired up, drove about 30 miles shut it It might be a bad EBCM, but there is definitely something else weird going on with the databus because in your videos the cluster appears to lose communications with the ECM toowhich is why your oil pressure drops to zero, the fuel level drops to zero, and the security light comes on. Bought it in August with no issues. I'll definitely go through the list of items you have there and verify the circuit is good/bad. It was a bad, broken remote starter box that is located in the back, drivers side column behind the rear seat that when broken it shuts down the entire truck. because for whatever reason the ECM stopped sending The fuel injection control module (FICM) is an important part of your Duramax engine and if it is experiencing issues this can greatly affect the performance of your vehicle. The real question is how do you prove bad component vs outside issue (or mishandling, physical abuse). Discover when DIY works or it's best to use a professional diesel shop. Reading reviews of Flagship seems to indicate that they give out a good rebuilt ECM about half the time, so Just started today while driving home. I seem to be getting the run around with them and they tell me this particular model is hard to find parts for. Hey guys, I am new here but have read through your forums ALOT to get answers on previous problems with my truck. Took it by my diesel shop and #5 injector showed bad with others way out in negative 2008 Duramax No Crank Bad ECM replacing damaged ecm wiring harness Jump to Latest 11K views 17 replies 8 participants last post by aaron. Found signs of mice chewing on wires also. So i got the "Exhaust Fluid Quality Poor" issue. I spent a good deal of time and read every 2610 code post on the forum I saw one instance where the ecm was bad and needed to be replaced. It also comes standard on most stroker CP3 pumps. I was having issues with dpf related hardware a few days I shut it off, banged on the tcm, cleared the codes (I got ECM U0101 and ECM P0700), then drove home with all the same issues and it was locked in 3rd gear. Ran a little ground wire off the ECM last night and i was able to fully communicate with ECM and see four DTC's, troubleshoot them and all four end Aug 19, 2021 · I’m trying to help my buddy with a new-to-him LBZ. I plan to get a current Hate to post because it looks bad on my behalf as a tech, throwing pride out the window to get this truck out of my shop. 2016 GMC Sierra 2500HD Denali, Flo-Pro 5" and Kory Willis tuned (Sold) 06 LBZ 2500 4x4 CC/SB Arctic White MBRP, S&B, EFI Live, Leveled, 35's, 20" Novakanes (Sold) 2007 C6 From ECM testing to replacement, learn the common Duramax ECM issues and best practices for repair. 0L - Old Trucks: 1 - LB7, 3 - LLY, 1 - LBZ, 2 - LMM, 1 - L5P Cliffs: Truck gives P0090 Dealer diagnoses bad ECM. There is no continuity from case of the ECM to pins 2,4,6. In this video, you will learn 4 symptoms of a bad or failing engine control module. I went and got a rental car so I wasn't stranded for the weekend and started the truck when I got back home. Two days later they came back saying NOx sensors tested out of range and need replacing at a cost of $1,700. 5K views 5 replies 4 participants last post by Ron Nielson Mar 2, 2023 Shop tells me my ECM is bad, but GMC does not still make them. Sent ficm and ecm off to g7 computers they said both had software issues and fixed and sent back still no power to ficm. See full description below. I checked for harness rub, found nothing, i'm thinking the ecm is bad now Mar 29, 2025 · You pull the ecm (technically you can still do it in the truck) and attach a harness with the needed pins to power the ECM and connect to the communication pins. Learn the key signs of ECM failure, its role in engine performance, and how to diagnose issues to keep your car running efficiently. 0 LM2 Duramax that has a bad ECM. I ended up ordering a new ECM swapping it out and all my problems went away. I was driving last week and while stopped at a stop light the enigine began idling really rough then the "low oil pressure" warning came on, then Ground case of the ECM and I have communication with the ECM again. runs good now. I ordered a used ECM off of Ebay Duramax owners and truck enthusiasts, it's time to take back control of that pesky "Service Emission System" warning! You know the power and performance that comes with owning a Duramax engine, but seeing this warning can be a source of frustration and disappointment. I I was going to post this in the other thread titled ecm fryed but i didnt incase anyone eles has problems. Duramax 3. 5v down to 12. Replaced with spare 20 amp fuse, truck started right up and ran for about 3 minutes then stopped. Soon after, it started what sounds like a gasser with timing off, A loud knock. Symptoms Of A Bad Engine Control Module (ECM) The most common symptom of a bad engine control module is a check engine light on the dashboard. But no check engine light Also the lights dim every 5 seconds or so when at idle, the voltage goes from 14. I've got a new ECM on order with the dealer, but it's already been over a month and even the Chevy corporate help department says it'll be at least a few more months before I get a new ECM. After all, a new ECM can cost a lot of money and you want to be sure that replacing it is going to resolve your customer’s concern. Since the truck is over 5 years old the dealership could only install refurbished ECM's due to new ECM's for my truck were no longer manufactured. anyone figure this out? I've got a 2020 Silverado with a 3. I was wondering if the BCM or ECM had gone bad and keeping everything from working it starts and runs fine I just don't have any gauges or Windows or locks it's a 2003 lb7 2500 hd. Repair service for damaged and corrupted Duramax ECM/TCM’s. I think that I had one bad battery that may have shorted out and hurt the ecm. The pickup is still at the dealership because they are trying to figure out the P 2610 code. I have a funny feeling that the ecm is still not working. In this post we will take a look at some of the biggest indicators that the FICM may be failing on your Duramax engine. Having a couple issues with my 2013 Duramax 75,000 miles Show reduced power on the instrument panel and it feels down on power, maybe 75% of normal. If your car won’t start at all, that’s another strong sign your ECM is bad. Two days later truck is Has anyone ever experienced a failure of the ecm or a corruption of the programming where it was tuned post a dpf permanent fix? In 2021 in Alberta Canada where it was not an issue with any regulatory bodies to perform a dpf permant fix…. Any input is greatly appreciated! I have a lot of time and money into this truck and I'm so close to getting it back on the road! And the kicker, ecm won’t communicate then it’s bad. Research said bad NOx sensors. No power at all. It's normally going to be an issue with wiring/voltage. In a 4500 GMC. Let me say that I have been using this forum for years and just now joined do to an issue that I have not been able to solve by searching the forums. Thanks for all the troubleshooting info, jc. talked to a couple people and they say the LB7 ECM has issues with a certain portion of the circuit board that goes bad. All good until suddenly both P0090 and P0045 and limp mode. The truck didn't actually die that time, his electronics just went nuts for a short period then all went back normal. What are the signs of a bad FICM on a Duramax? What causes them, and how to fix them? The right diagnosis and right course of action can prevent a bad FICM. Engine is hard to start, hesitates, blows white smoke, and is only making 2000-3000psi of fuel pressure all without throwing a code. Will report back with findings afterwards And again I assumed that it was a bad ECM that was installed. Need to get a tech 2 on that thing, check ALL the sensors, could be a junk ecm or bad wiring. I want a reputable place for this to be done. The TCM seems to be fine. Added new def, drove it to get it to regen and clear, and nothing. It's the ECM that seems to be the issue. All the LOW reference circuits on the ECM DO have continuity to the case. Dedicated power and communication. Every time i have DTC i check circuits, replace the part and then end up with a new or same DTC. I took my truck back to the dealership and they had it another week replacing the ECM again. I had been having ECM/Injector issues over the past couple of years and could never narrow it down even after all new injectors. I checked wires from FPR back to ecm and no breaks or knicks. What happens if nothing is plugged into the DLC connector? Still have same problems? Have an aftermarket radio? What other non-stock electrical things do you have? I wouldn't jump to bad ECM unless you can prove that the ECM is really the problem. I know this is a long shot, but is there somebody around the Baltimore, MD area that would be willing to lend me a spare ecm so I can test to see if the one on my truck is bad? Truck is an 07 Vin D Reading through the old posts because I don't remember everything, I ended up not getting the ecm flashed and never put it in. We strive to keep this the #1 forum for tech and information while continuing the push for new and exciting tech on the Duramax platform. a. my 1991 gmc sonoma had corroded wire to ecm and the truck would not start due to bad connection to the fuel injecter not getting enough power,mechanic cleaned and re-worked wire to connect better to ecm, about a month ago. Aug 3, 2021 · No power to ficm truck was running really good up as died one day. 6LLY duramax ECM. Hit the next level of limp after I did the 100 miles, so limited to 65mph now. Yesterday it was hard to start and runs horrible then dies. mcphee Feb 2, 2025 Need some inputs on the charging system malfunction, please 2007 Sierra 3500 Classic / LBZ / WT trim / dual batteries, single alternator system. Grounds on pin 2,4,6 on C2 of the ECM will burn a headlamp. Symptoms include no-start conditions, engine stalling, or erratic performance. Shop Now! ISO: A Pin out diagram for a 2004 6. cwzl, n26gnv, vvtlj, gerk, 5vzrzd, yfwgc, gchdo, fhba, w61oh, wbusi,