2018 Chevrolet Tahoe Electrical Problems

After your dealership installed a new Body Control Module (BCM) in April 2025, your trailer braking system has malfunctioned, causing unintended brake activation that pulls your vehicle to one side — creating a safety risk. The dealership initially said you needed a BCM replacement to fix a tire pressure monitor error, but now claims the brake problems aren't related to the BCM. You may need the BCM reprogrammed or replaced again, though the dealership is charging $600 in labor to attempt another fix.

My vehicle started announcing service trailer brake system when i purchased my vehicle about 5k miles in i took it to the dealer they couldn't find anything wrong now that message started to get worse not only is it a safety concern due to the annoying beeping. Sound on the dashboard indicating something is wrong. It makes me take my eyes off the road it Constantly distracts me every time it goes off. Also, feel every time that message appears. My truck slows down. As well, a safety concern when pulling a trailer. The brake system could fail on the trailer due to trailer brake assist malfunctioning.

I was sold a vehicle from a dealer in Arizona that online says they only sell to government or law enforcement

Purchased brand new Chevy 2018 Tahoe in April 2019. Overall good car never had any issues until 02/08/23 as I was driving a got a service alert "Trailer Brake System", It was so random since we have not hauled anything for that to even become a problem. The next day 2/09/23 the car was not drivable it wouldn't turn on it kept giving me the same alert "Trailer Brake System". I called the dealership and they said it's a defect and have to take the Tahoe in for service since only they can find the defected harness and now I have to pay out of pocket for something that I did nothing wrong, something that is manufacture defect and completely unsafe to drive.

Trailer brake system warning, I can’t drive, because it buzz me off! Never used trailer.

Entire vehicle loses electrical power. The vehicle does not shut off, however. Lights, dash, display etc. Possibly a grounding issue. Problem has not been looked at yet, but has occurred twice in the last week. No warning lights available. Occasional park assist failure occurs, may or may not be related.

PASSENGER WINDOW WHEN ROLLED UP IT ROLLS DOWN AUTOMATICALLY. BUTTON HAS TO BE HELD IN THE UPWARD POSITION FOR WINDOW TO STAY UP. HAS ALREADY BEEN SERVICED BY DEALERSHIP.

ON OR AROUND OCTOBER 16 2019 I WAS DRIVING MY 2018 CHEVY TAHOE WHEN THE RADIO STOP PLAYING. I PULLED OVER IN A HOTEL PARKING LOT TURN THE VEHICLE OFF OPEN THE DOOR AND THEN STARTED THE VEHICLE BACK UP. THE RADIO DID NOT WORK. I WENT TO MCDONALD'S TO HAVE BREAKFAST IT WAS ABOUT 30 MINUETS BEFORE I GOT BACK IN THE TRUCK STARTED IT UP AND THE RADIO STATED TO PLAY. I THOUGHT IT WAS STRANGE SO I CONTINUE TO DRIVE 2 DAYS LATER MY CHECK ENGINE LIGHT CAME ON SO I TOOK IT BACK TO THE DEALER TO SEE WHAT WAS WRONG. THEY TOLD ME THAT THEY CLEAR THE CODE AND NOTHING WAS WRONG WITH THE VEHICLE SO I THEN GOT AN OIL CHANGE SINCE THE VEHICLE WAS ALREADY IN THE SHOP. ON NOVEMBER 2, AT AROUND 3:20 MY CAR RPM WAS ON 5 AND THE SPEED LIMIT WAS ONLY 23MPH. THEN THE CHECK ENGINE LIGHT CAME BACK ON. I CALL THE DEALER AND EXPLAIN THE SITUATION AND THE TOLD ME TO BRING IT BACK IN THE NEXT DAY. WHEN I STARTED THE VEHICLE AND PUT IT IN DRIVE THE VEHICLE MADE A HUGE THRUST AS IF I WAS HIT FROM BEHIND. IT'S BEEN A WEEK NOW AND MY VEHICLE IS STILL IN THE SHOP.

I WAS UNLOADING GROCERIES FROM THE BACK OF THE CAR. THE TAILGATE SENSOR UNDER THE CAR SENSED MY FEET AND BEGAN TO CLOSE. THE TAILGATE CONTINUED TO CLOSE ON ME, NOT STOPPING AFTER COMING INTO CONTACT WITH ME AS I QUICKLY DUCKED OUT OF THE WAY.

ON THE EVENING OF NOVEMBER 27TH, MY CAR WITH 10,200 MILES HAD MULTIPLE ISSUES MAKING IT UNDRIVABLE. I ATTEMPTED TO PULL MY CAR OUT OF A PARKING SPACE. WHEN I PUT THE CAR IN DRIVE, I FELT A HARD THRUST. THE THRUST WAS SO HARD THAT I FELT LIKE A CAR HIT ME. I ATTEMPTED TO PUT THE CAR IN REVERSE; HOWEVER, IT WOULD NOT REVERSE WHEN I STEPPED ON THE GAS PEDAL. WHEN I PUT THE CAR IN DRIVE, IT BARELY MOVED. AS IT MOVED, I FELT THE POWER STEERING LOCK, AND I COULD NOT MOVE THE STEERING WHEEL. I TURNED THE CAR OFF AND ON THREE TIMES AND ENCOUNTERED THE SAME ISSUES. AT THIS POINT, I WAS STUCK IN THE MIDDLE OF A PARKING LOT IN A ODD PLACE WHERE CARS HAD TO GO AROUND ME. WHEN THE TOW TRUCK ARRIVED TO MOVE THE CAR, THE DRIVER ENCOUNTERED THE SAME ISSUES. HE POINTED OUT THERE WERE NO RPMS ON THE CAR. THE TOW TRUCK DRIVER HAD TO TOW THE CAR FROM BEHIND, AS I WAS STUCK IN AN ODD POSITION AT THE EDGE OF THE PARKING LOT. AFTER TWO WEEKS, MY CAR REMAINS AT THE DEALERSHIP. THE DEALERSHIP STATES IT'S A COMPLEX ELECTRICAL ISSUE. THEY ARE WAITING TO FIND OUT IF GM CAN FIX IT OR WORSE....THEY WILL JUST GIVE IT BACK. I AM BEGGING TO HAVE THIS INVESTIGATED AS I WOULD HAVE FOR ANYONE OR MYSELF TO ENCOUNTER THIS FAILURE WHILE DRIVING.

BACK UP CAMERA HAS ZERO VISIBILITY WHILE BACKING UP DURING NIGHT IN DARK AREA WITH RAIN CONDITION. THE REAR BACK UP LIGHTS DO NO ILLUMINATE ENOUGH LIGHT TO GUIDE THE VEHICLE. THE CAMERA IMAGE IS TOO GRAINY, DISTORTED AND PIXELATED.