Electrical System Problems of GMC Sierra 2500 - part 1

On 07/10/2026 at approximately 1:10 a. M. , the parked and unoccupied vehicle caught fire while turned off. The vehicle had not been driven for several hours. A neighbor was awakened by the horn/alarm and popping noises, observed fire near the passenger-side cab/engine area, and called 911. The fire rapidly spread throughout the cab, engine compartment, rocker-panel areas, wheel wells, and truck bed, creating an explosion hazard and threatening a nearby occupied residence and garage. The fire department extinguished the blaze, but the vehicle was completely destroyed. Before the fire, the vehicle had experienced recurring coolant warnings, a def-system warning, and delayed starting associated with the main battery. No smoke, fuel odor, intentional ignition source, charging device, or known external fire source was present before the incident. Weather was calm. The exact failed component and cause remain unknown. A firefighter stated that the apparent fire origin was near the passenger side of the vehicle. The remains are available for inspection, subject to coordination with the vehicle owner and insurer. The incident has been reported to the fire department, insurer, manufacturer, and NHTSA.

See all problems of the 2019 GMC Sierra 2500 🔎.

On xxx, I was towing my camper to copper center, alaska from palmer, alaska when my truck experienced a full transmission shut down which put the truck into "reduced power mode". We descending down the road right next to victory bible camp (64741 victory rd, sutton-alpine, ak 99674) when the exhaust break turned off and the truck decreased power and the check engine light illuminated. The diagnostic that was produced by onstar revealed 3 different codes. ( p0700 tcm, p0747 pressure control solenoid a is stuck in the "on" position, c116b faulty brake pad wear sensor. ) I called GMC of palmer and GMC onstar advisor, both informed me that the truck needed to be towed. My safety concerns is this. . . . I had minimum cell phone signal and not a gas station or service station within miles. I was on the side of the alaska highway 1 which is a major thoroughfare for traffic going to and from [xxx]. Thankfully there were a few kind folks that pulled over to offer assistance. My truck is a 2023 GMC Sierra 2500hd with only 26,262 miles on it. I purchased this vehicle xxx. (it still has the temporary tags on it. ) if had been in a different part of alaska when this transmission failed to function properly then we could be talking about a life or death situation. Especially, if my child was with me. I was hauling my camper that weighed atmost, 7,000 pounds. This is less than 40% of the trucks ability. I feel that this could put someone into a dire situation had they not had the experience with emergency situations like I have had. (prior military service). I have also filed a complaint with GMC motors. Case# xxx. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

See all problems of the 2023 GMC Sierra 2500 🔎.

The contact called on behalf of an insurer who owns a 2026 GMC Sierra 2500. The contact stated that 15 minutes after the vehicle was parked and turned off, a neighbor informed the owner that the vehicle had caught on fire. The owner and the neighbor extinguished the fire using water hoses. The contact stated that the fire originated under the rear passenger’s side seat and was caused by an overheating amplifier that had short-circuited. No warning light was illuminated. The fire department responded to the scene and filed a report. There was no police report filed. There was no injury or property damage. The vehicle remained parked, and the owner intended to return the vehicle to the dealer. The owner was provided a loaner vehicle. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure, and a case was opened, but no assistance was provided. The failure mileage was approximately 9,000.

My hmi was "bricked" when onstar pushed an incompatible update when I changed the service plan. While driving the screen has intermittently turned off and on causing temporary unexpected loss of navigation functions, bluetooth connectivity, and use of the back up camera. This causes a safety issue as the unexpected loss of display and connectivity has caused me to be unable to continue using hands free features during operation, and to no longer view behind the vehicle during entirety of backing. When I contacted onstar support I was instructed to perform some troubleshooting and was then referred to the connection center team. The cct representative told me that my hardware was outdated and could not support the update. If a representative can confirm the problem retrospectivly, I think the representatives making changes to the service plan should also be able to proactively confirm incompatibility before causing the issue. There were no warnings. The issues first occured while I was driving on the day (6/25/26) my new plan began and the update was sent. I can make the hmi available for inspection upon request. I don't believe there is any actual issue with the hardware, just a negligent and incompatible software update.

See all problems of the 2016 GMC Sierra 2500 🔎.

During normal use, the factory wireless phone charging pad in the center console overheated, produced visible smoke inside the cabin, and melted the charging surface area. No liquids or foreign metal objects were present. The phone was placed normally on the charging pad. The incident created a burning smell and visible damage to the interior trim. The system did not shut down before damage occurred. This appears to be a potential electrical or thermal safety failure in the factory-installed wireless charging system.

Gm duramax l5p diesel engine electrical connector for #4 fuel injector. This failure caused the diesel exhaust brake, which controls downhill speed, to disengage, extreme shaking of the vehicle, emissions system warning and speed limiting. This occurred while descending a steep grade while towing a 34 feet long, 10,000 pound trailer. This is a known issue with this diesel engine and documented in gm technical service bulletin 23-na-027. Inspection and repair at a gm dealership confirmed a known issue with the #4 injector pigtail connector caused by improper wire routing and interference wit the sound shield and valve cover heat shield this was a sudden failure of the #4 pigtail connector with no advance warning. In addition to violent shaking of the vehicle, multiple warnings on the dic indicating that the diesel brake was disengaged, the emission system had an issue, and speed would be limited.

See all problems of the 2018 GMC Sierra 2500 🔎.

My 2022 GMC Sierra 2500hd was previously repaired under gm safety recall n232426400 / NHTSA recall 24v060 for the power-unlatching tailgate switch, which can fail from water intrusion. The recall repair was completed and the recall now shows as closed. Recently, the same tailgate switch problem occurred again. The dealer diagnosed water intrusion/corrosion affecting the tailgate release switch circuit, including damage to the related wiring harness/connector. GMC customer assistance stated they could not assist because the recall is closed. I am reporting this as a possible failed or inadequate recall remedy. The same water-intrusion condition addressed by the recall appears to have recurred after the recall repair, and the vehicle now requires additional repair to the same tailgate release system. This raises concern that the recalled safety defect was not fully remedied and that other vehicles may experience repeat failures after the recall is marked complete.

See all problems of the 2022 GMC Sierra 2500 🔎.

Iok radio module failure. Inhibits hands free calling, total loss of all audio including safety chimes, dropped emergency call capability, multiple software updates have failed to resolve it. Vehicle is still under warranty.

See all problems of the 2024 GMC Sierra 2500 🔎.

Intermittent trailer disconnect and loss of electric trailer brake output while towing airstream. The truck is connected to the trailer through the seven way plug. There are no modifications to the truck. This is a safety hazard as I pull a 9000+ lb trailer. Trailer connection drops momentarily and integrated trailer brake controller loses communication with trailer brakes. I went on a 5000 mile trip and my trailer brakes were connecting in disconnecting consistently. Every time there was a disconnection or connection the vehicle would “ding ding. This virtually happened consistently while we were on this long trip. During the trip, we tried to wedge the plug tight and zip tie the door shut, attempting to keep the plug tight. My truck is at the dealership, waiting on a “tool“. This is the second time it has been in the shop for this issue. I supplied a picture of the dash message after it got tired of connecting and disconnecting. I feel this is a serious safety issue. Thank you, [xxx] information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

The vehicle went into low power mode and said to pull over. As soon as that message appeared the next warning appeared and said to shift to neutral and pull over immediately and attempt to restart. The vehicle immediately shut off after second warning before having time to pull over from first message. I was able to pull most of the way off the road as the vehicle had shut off there was no power steering and had limited ability to steer the vehicle. This all happened without advance warning or any other warning that there was an issue while traveling at over 75mph. Vehicle would not restart and needed to be towed. Dealer stated it was a fule control module that was hard to get due to a recall. But that my vehicle was not part of that recall.

Ui bulletin #161b is for years 2020 and beyond. But my 2019 is having the same exact issue and the gm dealer will not cover the work as stated in the ui bulletin #161b.

Iok radio module failing. Would happen 10 times in less than 5 miles. Vehicle has been seen 3 times before diagnosing as iok radio module failure. Inhibits hands free calling, total loss of all audio including safety chimes, dropped emergency call capability, multiple software updates have failed to resolve it. Vehicle is still under warranty. Serviced at garrett motors in coolidge, az.

Onstage control module fail and drains batteries leading to power failure.

Radio has zero sound - the issue is the radio sound also has the blinker sound, hands free safety/navigation guidance along with the on star safety function. None of that is functional. The dealer states it's a known issue and parts are not available. How can this be when they keep building new units. Gm has been contacted with zero help and no response around my safety concerns. While it seems like a small thing when we say radio I'm not concerned with the lack of music but this system controls way more than music.

About 2-3 months ago I had a battery swell up and start smoking and making an awful smell in my truck. I took it to dealership and was informed that I needed a new battery and it was not covered under bumper to bumper warranty or my extended warranty which I thought was ludicrous. The truck is 18 months old. It does have 50,000 miles but I have yet to see one that isn’t at least prorated for five years. So fast forward to today and the other battery starts doing the same thing except this time my lights are going crazy. Brights on and off and on and off. I get back to my camp and the battery and wiring is smoking like crazy. I towed it to the shop. It’s been in there two weeks and the only thing they tell me now is that I need 2 new batteries and that’s all they can do until I agree to pay for the other one that isn’t under warranty (because I already paid 300 to change 1st one it’s under warranty for 5 years). So I told them to do it. It’s been there two weeks and not a damn thing has been done. Not even installed a new battery. I know because I went yesterday and they couldn’t open my tailgate to get my tools out. Probably the last GMC I purchase.

The main tailgate will not go down or function properly and it says online there is a national recall for this, but does not come up when I search my vehicle. When I turn on my left turn signal the brights flash for no reason and this is a known major issue with the vehicles as well. The trucks computer is telling me low on coolant even though it is not that has already been fixed through a 3rd party warranty parking brake was stuck on when I bought the vehicle and had been for a long time you could tell and I had to pay over $1100 to fix it at gm. The Ford collision system does not work properly and the cameras will come on at certain times when they're not supposed to be and not come on when they are supposed to be.

See all problems of the 2020 GMC Sierra 2500 🔎.

My center console wires for the charging pad broke and shorted out causing wires to burn and short the whole system out.

The rear defroster massively overheated. It started heavily smoking and eventually exploded the rear windows. Only warning sign was the smoke which we noticed quickly because the windows were up. Had the windows been down we might not have noticed before a fire started. I'm taking it to a dealership now. This module also triggers on from a remote start. Extremely dangerous!!!.

After driving my truck, once I park and turn the truck off it will not shut down electronically due to an error on the dash display that reads “shift to park”. Sometimes I have to mess with the gear shifter when the truck is in park to get it to register that it is parked and shut down completely. It can take up to 15 minutes sometimes to shut down.

This vehicle exhibits the same failure described in NHTSA recall n232426400 — spontaneous unlatching after rain due to water intrusion into the exterior tailgate release switch. I’m requesting a goodwill replacement under gm bulletin # n232426400 as the failure mechanism and part are identical. It has caused brake failure and nearly killed me because of battery drain while driving. All american Chevrolet of midland texas is refusing to solve the problem and says no recall is available.

Led instrument cluster goes blank. No speedometer, no fuel gauge, oil gauge, nothing.

During a drive home, while in motion, the tailgate of the vehicle opened on its own. This has occurred after the recall to repair this issue was already performed. I know the tailgate was shut prior to the drive because I back into my parking spot and walk the sidewalk behind my truck prior to starting the vehicle.

After placing the vehicle in park and try to turn it off, I receive a message saying “shift to park”. The engine is off and in park, but the vehicle doesn’t recognize it as being in park so all of the electrical stays on. I started complaining about this to the dealerships before my warranty was up but they kept giving me the run around avoiding the fix and now that the warranty is expired they want to help me for a ridiculous fee. This issue happens randomly at least one day a week.

I was driving my 2022 GMC 2500 hd (not towing, just normal drive) after an oil change <900 miles ago and new brakes/rotors 3 days prior <100 miles (total mileage 81,000, serviced exclusively at GMC dealership) when the loss of power alert flashed on the screen. I was 2 miles from my destination, going approx 55mph, so I kept driving to destination, when the vehicle stalled in driveway. As I was scrolling through menus to see the alert I looked up and smoke and flames were coming out of the engine. I attempted to extinguish with a fire extinguisher I had with me, but it was no use. The entire engine was engulfed, melting out, tires and windshield exploded from heat etc. Total loss. Vehicle was inspected by insurance CO fire investigator, no origin confirmed due to extent of damage. Vehicle was offered to GMC for their inspection as it was partially under oem warranty and I had an extended warranty from dealership, which I also notified. Extended would not do anything without the vehicle at GMC and diagnosis, which again, there is no engine etc so not repairable. GMC was to be in contact with insurance CO. No status update received.

The manufacturer placed two 12v batteries to start the truck with one being located on the passenger side just in front of the cowl of the cab. The factory oem batteries are known to overheat when charging which is exactly what mine did and as the battery boils over with sulfuric acid, the acid is vaporized and ingested into the cabin. It’s a diesel so it’s common for me to take my dog in the rear crew cab with me and leave the engine running so the cabin will stay cool in the summer while I work my contractor job. When I let the engine idle with windows up and ac on the overcharged battery introduced the vaporized sulfuric acid into the cabin and rendered the interior deadly toxic. Luckily I was only gone from the truck for about 10 minutes but in this amount of time the acid was very bad and caused burns in my dogs throat and mine while driving home. I can only imagine if this scenario were to take place with kids left in the truck for many reasons to stay cool but could easily turn into a deadly situation. Please look into this before someone or some poor animal is fatally injured or killed.

I rely heavily on this vehicle for my business and within 1 year of ownership, the vehicle broke down on the highway allowing it to only run @ 30mph. After finally locating a dealer who could evaluate the vehicle in less than 1 week, I was informed that the part was unavailable and they indicated, "it could take 1 month or 3 months to receive. " following multiple conversations, I was forced to open a claim with gm customer care. While trying to get information, I was, at one point, told that "although the code indicates failed transmission control module, it doesn't happen all the time and if I wanted to drive it I could come and take it until the part arrives. " that really told me alot about how gm representatives view safety while when it happened, I was on interstate and nearly got trounced by oncoming heavy traffic while pulling an equipment trailer. After the case was handed off to several gm customer care representatives, I finally rec'd feedback including several email updates. I finally rec'd the vehicle back after 1 month and was informed that 1) would receive car payment from gm & 2) would receive additional compensation for lost work time while my vehicle was out of service (Jan 2024). Since that conversation, I did receive 1 car payment however, never heard back from alisa regarding "lost time". I have sent several emails to customer care asking for an update however, crickets. Furthermore, the car has returned to the shop for another warning to "shift vehicle to park" when it was in park. They told me its a electrical malfunction but they could not get the error to come up on test. I have a photo showing the error.

Shift to park message displayed while attempting to shut off engine after shifter was in the park position, accessory would not turn off even after driver door opened and could not leave vehicle.

The contact owns a 2023 GMC Sierra 2500. The contact stated that on several occasions, after the vehicle had been parked for approximately two days, the vehicle failed to start. The vehicle was jump-started and taken to a dealer three times, where it was diagnosed and determined that the battery needed to be replaced. The vehicle was repaired three times, but the failure persisted. The manufacturer was notified of the failure, and a complaint was filed. The failure mileage was 33,000.

Having issues with inner tailgate opening on its own and items falling out of bed/box onto road!.

Vehicle was parked in a school parking lot. Rear trailer harness and modules in back short circuited causing an electrical fire that expanded to the driver’s taillight rear bumper, and bed of truck.

024 GMC Sierra 2500 denali ultimate, which has suffered: •five catastrophic engine failures at highway speeds. •total brake failure, leaving the truck unable to stop. •severe electrical malfunctions, including flickering headlights at night. •retaliatory actions from general motors after I refused to waive my legal rights. I have documented proof, including gm’s own service records, emails, and a 7-minute recorded statement from gm’s highest-level technician, confirming that gm installed the wrong computer module (1500 series instead of the required 2500 series) in my truck. Additionally, I have evidence that gm executives instructed technicians to conduct diagnostics, take apart the engine, and reassemble it—but not repair the defect—after I refused to sign an affidavit waiving my rights. Due to these failures, I suffered a dislocated shoulder in one of the incidents, and my [xxx] daughter remains traumatized to this day. Given the immediate danger this defect poses to other GMC Sierra 2500 owners, I respectfully request that NHTSA open an investigation and consider issuing a recall before a tragedy occurs. 1. Engine failures since 3,000 miles – gm’s own work orders confirm issue since purchasing my 2024 GMC Sierra 2500 denali ultimate, I have experienced five catastrophic engine failures, all occurring while traveling at highway speeds (70 mph): •the truck suddenly lost power, dropping from 70 mph to 5-10 mph within seconds. •this created an immediate risk of being rear-ended or losing control on the highway. •gm’s own service records confirm that my engine issues began at just 3,000 miles. •gm dealerships misdiagnosed the issue four times, returning my truck to me in an unsafe condition. •the real cause was only identified after the fifth failure, when a gm-certified head technician finally determined that gm had installed the wrong computer module (1500 series instead of 2500 series). This means that for months, gm knew my vehicle w information redacted pursuant to the freedom of information act (foia.

The side mirrors have spider cracked from some type of electrical issue. This is the 2nd time this happened and it burns both mirrors at the same time. The mirrors become unusable and it appears the dealer replaced them under warranty the first time and the second time they said it is out of warranty so I had to pay out of pocket.

When I am driving in town I have an indication message that comes up and says engine power reduced.

See all problems of the 2009 GMC Sierra 2500 🔎.

When I’m in reverse the up the cameras turn off. On one incident I was backing up and the camera turned off causing me to back up into the wall of my house.

See all problems of the 2021 GMC Sierra 2500 🔎.

Trailering a trailer with electric brakes. The vehicle intermittently reports connection issues where the brakes are temporarily disabled however the trailer lights are not effected. This leads to a period of time where there are no brakes on the trailer. Pretty confident we have eliminated the trailer as causing the issue.