Electrical System Problems of GMC Sierra 2500 - part 2

I leased this vehicle on may 17, 2024, expecting it to function as intended. Instead, within months, it suffered recurring and escalating failures that have rendered it unsafe and unusable. January 7, 2025, I brought the truck to gates GMC for routine service and reported that it had lunged forward by approximately 2 to 2. 5 feet while shifting into park. Additionally, it exhibited irregular acceleration and rough down shifting in lower gears. I also communicated the check engine light has come on and gone off on the dashboard over the past week a few times without receiving any information on the app. At this January 7th visit, gm performed recall n242435631, supposedly addressing a known battery drain defect that caused total vehicle shutdowns. On January 24, 2025, I started the truck and was immediately overwhelmed by an intense chemical odor coming through the ventilation system. January 31 – February 1, 2025 – erratic engine warning lights & diagnostic failures on January 31, 2025, at 5:28 pm, on this key cycle the check engine light illuminated but failed to register in the gm app. On the next key cycle, the warning disappeared. The following morning, February 1, 2025, at 10:26 am, the check engine light appeared on the first key cycle before disappearing on the second key cycle. The onboard diagnostics system failed to log or retain these warnings. On February 7, 2025, the vehicle suffered a complete electrical failure. No electronic function whatsoever. Roadside assistance attempted to jump-start the truck using a high-powered jump pack, but it remained inoperable. A Ford super duty and jump pack were needed to force start the truck. February 10, 2025 the truck suffered another total electrical failure and required towing to gates GMC. The app indicated the brake system, anti-lock braking system, emissions system (specifically the exhaust system), and power train requiring service. My truck is at gates GMC and was drawing 90 milliamps opposed to 40.

See all problems of the 2024 GMC Sierra 2500 🔎.

On 11/21/24 noticed passenger headlight day light running light flickering. On 11/22/24 right turn indicator intermittent fast blink, dash message stated turn indicator failure. Once home, inspected passenger headlight assembly. Found drl, turn signal, and low and high beam head lights were inoperative. On 11/25/24 went to GMC dealer/service. Staff seemed aware of issues and stated they are common, that they carry the $1,400 sealed assebly in stock. Vehicle is 4 months over warranty, but only has 29,000 miles. There is no visible damage to the assembly, but there is visible condensation inside the lens. Gm has a published service bulletin, 01-08-42-001p, that specifically addresses this issue for my vehicle. The earliest date the issue could be diagnosed/service date is 12/10/24. A complete failure of this non-servicable headlight assembly is an absolute safety issue. Decreased daytime visability with the loss of one of two daytime running lights, the lose of the front turn indicator to alert other drivers of my intentions, the lose of a set of low and high beam headlights. As mentioned, there assembies are a sealed led light assembly. If any one of these lights fail, the only remedy is the replacement of the entire unit with a $1,400 part. Gm has had multiple recalls of this same issue among their vehicle, but continues to produce the same failing pieces.

See all problems of the 2021 GMC Sierra 2500 🔎.

The contact owns a 2024 GMC Sierra 2500. The contact stated while reversing, the rear-view camera displayed a blank screen. The 4wd system engaged unintendedly, and the park assist sensor was inoperable while an unknown message was displayed. Additionally, the vehicle lost motive power while driving. The check engine warning light was illuminated. The vehicle was towed to the dealer, who replaced an unknown module and reset the computer, but the failure persisted. The contact stated that the vehicle was taken to the dealer five times, but the failure recurred after several unknown repairs. The vehicle was not repaired. The contact had requested for a buyback from the dealer, but no assistance was provided. The manufacturer was made aware of the failure. The failure mileage was approximately 8,000.

Smog system check and engan warning light keeps come on.

When it rains, there are puddles of water on the passenger side! cannot figure out how the water is getting in. . My concern is of a potential electrical short/ fire / failure of a system that doesn’t allow me to operate the vehicle safely! possibly, affecting other functions of the vehicle during operation!.

See all problems of the 2019 GMC Sierra 2500 🔎.

Vehicle was last driven on June 23 2024 and parked in my driveway. On the evening of June 29 2024 my horn was blowing in my truck at around 10:30. While I was walking out to the vehicle it was in flames. The fire started from what I understand on the driver’s side behind the dash. Luckily no one was in the vehicle when it happened.

Brake control module disconnects trailer brakes while towing. Apparently a known issue with trailers equipped with solar battery chargers which have higher charge than vehicle battery. It feeds back into the trailer brake power module causing it to shut down. The vehicle has an integrated trailer brake controller as it is specifically designed with primary function as a tow vehicle. Shutting down the integrated trailer brake controller results in loss of trailer brakes. Not having trailer brakes is critically dangerous. Gm has issued a TSB #23-na-149 specifically addressing this known defect. Unfortunately, gm refuses to authorize its service technicians to replace the defective brake controller unless they experience the defect personally - the policy is to disbelieve the customer with the defective vehicle. Effectively, this requires providing the trailer to the service tech to drive around until the brakes fail, thus creating another dangerous situation for a tech who may or may not have experience driving vehicles over 50’ in length. Thus, it would appear the best remedy is to enforce a recall to replace the defective brake controller before someone is harm by loss of brakes, since gm requires its techs to encounter a loss of brakes before authorization of replacement of the known defective unit. This happened over 25 times during a trip last week. This fact situation reveals why your administration actually exists - to protect the public from harm.

The contact owns a 2024 GMC Sierra 2500. The contact stated that the vehicle had failed to start on several occasions. The vehicle was taken to the dealer, where it was diagnosed with low voltage and electrical failures. The dealer replaced the two batteries; however, the failure recurred. The dealer then replaced one of the batteries; however, the failure persisted. The vehicle was towed to the dealer. The vehicle was not repaired. The manufacturer was notified of the failure, and the contact requested buyback assistance, but no assistance was provided. A case was filed. The failure mileage was approximately 22,000.

Electric trailer brake control modular is malfunctioning on my 2015 GMC sierra denali 3500. Multiple of sources told me this is a common problem with this generation of GMC.

See all problems of the 2015 GMC Sierra 2500 🔎.

Water intrusion resulted in the tailgate inadvertently unlatching while the vehicle is in park multiple times while being washed. This apparently happened throughout the night, assuming voltage was being used to send open signal, which resulted in drained battery. In my case my VIN is not on the recall that is out on GMC for tailgate issue. And dealership determined there is a pinch in tailgate speaker harness that is causing the issue. Which I’m sure that harness is tied into tailgate latch harness. What needs to be addressed in this recall is for the two drain holes on top of tailgate to be somehow sealed. Drain holes are directly above tailgate latch and harnesses which is the main concern in this problem.

The contact owns a 2024 GMC Sierra 2500. The contact stated while driving at an undisclosed speed, the sun struck the solar panel used to charge the battery, and the surge from the battery entered the pigtail going through the truck, and disconnected the brake module, causing it to become disengaged from vehicle. The contact took the vehicle to the camper and vehicle dealer who both stated there was no issue for concern. The vehicle was not repaired. The manufacturer for the camper and the vehicle were made aware of the issue. The vehicle failure mileage was 8,000.

While driving both drivers and passenger side blind spot warning lights flash on and off when no cars are near. The problem is worse at night when pulling a trailer. The lights sometimes stay on or starting flashing on both side causing a significant distraction.

The harness that hooks to bumper plug for trailer lighting is not completely water tight. Allows water in and creates buildup that weakens the connection as well as allows the plug wire connection to snap out and push out from the pin. Further inspection it was causing a short in the system. I attempted to clean and put some-electric grease on the plug to help clean it but then relaized 3 pins were broken and pushed back.

I drove from California to ohio after I bought the truck, I noticed that when stopping to get gas my tailgate was open without me touching it. I drove with cameras showing the truck bed to see what happened and I watched it do it again while driving the vehicle, it just opened on its own while driving. The incident happened again once I was back in ohio when I had my trailor hooked up and it cause the tailgate to collide with the trailor tongue and dented the whole top of the tailgate. 3.

While driving the entire dash cluster (speed,rpm etc) turns off entirely, reloads as if truck is just starting with all lights coming off and on, needles cycling max/min. Unable to recreate on command, multiple others reported same issue with no cause/cure listed.

Headlights and turn signals failed. Flickering of various lights (daytime running lamp, low beam, high beam, turn signals) followed by total failure. 3700 dollar repair at dealer to replace both headlamp assemblies. Barely over miles of warranty, but still in the 3 year warranty time period. Not having forward lighting is of course a major safety issue. Vehicle should be recalled. Many others are having the issue.

[xxx]: after arriving home and parking in my driveway (plugged in the block heater that came installed from the factory), approximately 35 minutes later my neighbor rang the doorbell. She was yelling that my truck was on fire! the flames were starting to hit my eaves on my house. I put the fire out with my hose. The sparks fire department had to pry open my hood to disconnect the batteries in order to stop the truck from lighting back on fire. The vehicle has been inspected by general motors and turned over to their insurance. My insurance has also inspected the vehicle and stated they believe that the wiring to the block heater was faulty. There were no warning lamps, messages or other symptoms of the problem. This truck has 19,000 miles and is 1. 5 years old (2022). How could this be turned over to gm's insurance and not under warranty? I have not had my truck for over 2 months now. I wonder how many of these trucks are lighting on fire? the truck is currently at the local dealership and is available for inspection. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

See all problems of the 2022 GMC Sierra 2500 🔎.

The contact owns a 2019 GMC Sierra 2500. The contact stated while driving at various speeds, the vehicle lost motive power. The coolant fan seized and failed to operate as needed. There were no warning lights illuminated. The vehicle was towed to the local dealer to be diagnosed. The contact was informed that the check engine warning light was illuminated, and the knock sensor, coolant fan clutch, injector #6, and unstated wiring harness needed to be replaced. The dealer informed the contact that the parts to repair the vehicle were on back order. The vehicle was not repaired. The manufacturer was contacted and opened a case, but no additional assistance was provided. The failure mileage was approximately 87,000.

Transmission control module I was at an intersection when the tcm malfunctioned halfway through and I lost all power to my motor. I was pulling a large trailer and cross traffic had to slam on brakes to keep from hitting me. My truck will not move faster that a few miles an hour now that it is in limp mode. I am a police officer and I had an onboard diagnostic tool that showed that there was no communication to the tcm. Stabilitrack warning lamp and check engine light are now on. It all happened at once no warning.

See all problems of the 2013 GMC Sierra 2500 🔎.

When the car is on and in park, there is a button on the front console that drops the tail gate. The truck gives you no indication that the button has been pressed or that the tailgate is open. You can then drive the truck with the tailgate open and have no indication or idea. As a result, it is easy to lose gear out of the truck bed while you are driving. This button is located just above a storage compartment and is easy to press while placing items in this compartment. This is a major safety hazard on the road. There is no option to disable this button or be alerted when you tailgate is open.

[xxx] has a trailer brake control module issue that causes the trailer brake to periodically disengage and reengage. Unfortunately, I had to drive across the country on a military pcs move with this intermittent failure. GMC has provided numerous surveys to ask about my experience with my new GMC. Overall, the vehicle adequate, and in each survey I have annotated this issue. However, it does not appear the issue is being taken seriously as I have not seen a recall. A trailer brake that intermittently fails is extremely dangerous. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).

Backing out of driveway, suddenly lost the transmission. I was stranded at about a 45-degree angle into the traffic lane. I had no gear position indication (an automatic) and couldn't move the truck under it's own power. Shut it off and restarted twice before I got it into "limp-mode" and, while abrupt and harsh, managed to get back into my driveway. Found fault code u0101, lost communication with tcm (transmission control module). Had never heard that this has become a common problem. Discovered quickly gm has no parts available, no repairs available, and that it is happening to thousands of gm trucks from model years 2008 to 2015. The truck is useless without this module function. We use this truck to tow a 12000+ lb. Travel trailer. I can't imagine how bad this could have been in freeway traffic with such a load. Have been told gm put the part on a national back order in October of 2022, with no estimate of availability. It's now late August of 2023 and still nothing available. Has me concerned that one of these vehicles could stall right in front of me in traffic! I can't afford to replace this vehicle, can't move it, and am relegated to going to work on a motorcycle- in traffic with other gm trucks just waiting to experience this failure. And winter is coming. . .

See all problems of the 2014 GMC Sierra 2500 🔎.

While braking ( after being on the highway) all dash gauges turn black, radio shuts off, ac shuts off. Service stabilitrak light comes on when dash flashes back on. While driving ac turns off, radio turns off same stabilitrak warning flashes, speedometer turns off. Power steer control went out while trying to turn. Truck put itself in 4 wheel drive when I turned on the trailer assist. Parking assist periodically turns itself off.

See all problems of the 2018 GMC Sierra 2500 🔎.

Defective trailer brake switch ,which poses a risk to motor vehicle safety if you are towing a travel trailer, where brakes fail lock up is possible dangerous to pull.

When attached to a trailer with solar panels, the truck will intermittently disconnect the trailer electronics which disables the trailer brakes and trailer lights. This is because the solar energy is back flowing to the truck via 7 pin connector and overloading the circuit. Having a truck disable the trailer brakes and lights intermittently is very dangerous. Earlier model years of this truck do not suffer this issue. Gm is aware and has TSB but no solution has been found on the truck side without disabling the solar panels on the trailer.

The integrated trailer brake controller does not work on this truck. Specifically, the part is the trailer brake computer module. Trailer brakes went out immediately and continue to disconnect at all times. The problem has been reproduced and confirmed independently. GMC has looked at the problem at dealer and stated they do not currently have a solution. Problem appeared immediately and has continued every single time a trailer is connected to the truck.

The column shifter that is installed on all 2024 GMC Sierra 2500hds and 3500hds poses a potential safety risk to its passengers and other drivers on the road. When the column shifter of the vehicle is in the standard drive position the shifter covers part of the screen and the direct path to the radio volume control dial and infotainment home button. It has been found and replicated that attempting to interact with the infotainment screen ui and the home button/volume control dial the driver may easily accidentally bump the shifter into the neutral position. Bumping this 8000lbs+ vehicle into neutral unintentionally can be extremely dangerous to its passengers and fellow motorists especially when hauling a heavy trailer or load like heavy-duty pickup trucks are designed to do. Bumping the truck into neutral can allow the truck to lose its acceleration capabilities and degrade braking capabilities as the engine would be disconnected from the drive wheels, limiting engine braking and exhaust braking. This kind of braking is commonly used to help stop the truck with heavy trailers and loads. This problem has been commonly referred to in multiple facebook groups relating to the 2024 GMC heavy duty truck. I personally have not had it inspected by any third party as there is not much they can do to remedy the issue. I personally recommend that general motors redesign the column shifter in these trucks shortening it to come no further than the diameter of the steering wheel eliminating any interference with the infotainment system and the home button/volume dial. Gm shall replace this updated shifter free of charge in all trucks just recently built. For gm's sake, it is important that this issue is remedied ASAP as the truck just began production and there is a limited amount on the road. This is available for inspection upon request.

Failed transmission control module (24256861). While driving in the early morning hours (darkness) taking my child to school, I was navigating through a busy intersection when the vehicle surged and then made a loud metal on metal sound, feeling as if someone had struck me from behind. At that point the power train became inoperable, stranding us and coming very close to being first, struck from behind and then from cross traffic. The vehicle was/has been inspected by a gm technician at starling Chevrolet, st cloud, FL and the tcm was found to have failed (trouble code u0101, lost communication with tcm). It has been at the dealership for going on four months awaiting the production of a replacement part(tcm). There was no prior indication that the tcm was about to fail. Upon failure, all lights on the vehicle display flashed and the indicator for the vehicle drive position was lost (p, r, n, d), no longer visible.

See all problems of the 2012 GMC Sierra 2500 🔎.

The high beams quite working.

Driving on the expressway around 60 mph when the truck went into limp mode slowing me down to 40 and then would not shift gears tcm went out gm told me that there is a big problem.

I remote started my truck yesterday morning to get it warmed up before loading my family. They all then got into the truck, my 5 year old and 8 year old in the back seat in booster seats. I threw in some more bags into the back of the truck and started to climb into the truck. As I did that my kids were starting to get nervous and my wife was pointing and stating that the rear window slider was smoking. I put the key into the ignition and turned the key on. Upon doing that the smoke stopped but a few seconds later there was a loud bang, similar to a gun shot, and the rear passenger side window shattered. My 8 year old had glass hit her and my 5 year old was hysterical. Needless to say, the 5 hour drive home was not much fun for anyone after that occured.

See all problems of the 2016 GMC Sierra 2500 🔎.

I am receiving an on-and-off “service trailer brake system” when towing and sometimes when not towing. Checked every component and alert does not stop. When this happens while I’m towing, trailer brakes stop working momentarily.

I have a 2018 GMC sierra duramax quad-cab and when it is connected to either my boat, stock trailer, or cargo trailer the lights and electric trailer brakes on the trailers do not work. And the chime from the "service trailer brake" indicator sounds and doesn't stop until I unplug my trailer harness from my truck making it a distraction and an unsafe situation when trying to navigate through traffic(changing lanes, stopping, and other functions needed when hauling trailers). The dealership said it was a module and specified which one and so I elected to replace it myself and it wasn't the issue. I choose to do the work myself as they quoted me a price of $700. 00+ to repair the problem.

2016 GMC sierra shark fin antenna gets water under and destroys onstar, navigation, and compass operation. This is recalled in 2015 but does not include 2016 that have the exact same problem.

Bought the truck brand new. Within a week the service trailer brake warning light came on. Has been to the dealership 3 times and they still cant fix it. This affects towing of the trailer with no trailer brakes.

See all problems of the 2023 GMC Sierra 2500 🔎.