msfrommars
New member
I have a 2015 Sonic LT 1.8L that I bought pre-owned from a used car dealership in August. Almost immediately after purchasing it, I had to get a number of repairs that were not issues that had been disclosed in the sale, so I apologize if this comes across a bit frustrated. I wish I knew more about cars to understand what's been happening, so I'm turning here for help.
In the past two-ish months, occasionally while driving, the car locks would go up and down a few times and while this is happening, the car would put itself into what felt like neutral. I'd be in stop-and-go traffic revving unable to move for about 2 to 3 seconds. In the past 3 weeks, this has escalated from being infrequent to happening almost every time I'd use the car. It began to go from a "quirk" to feeling really really unsafe, so last week I brought it into my usual mechanic. No warning lights were on, but even simply starting the car would cause the locks to "freak out" if that makes any sense, and the indicator for the gear I'm in would flutter displaying reverse, drive, neutral, etc.
Their first diagnostic scan indicated 29 codes in the BCM so I got the BCM replaced (inc. labor) for $1212. Within a day and a half, the issue happened again, so I re-brought it in and they examined the battery cables and gave me a new battery ($289). At this visit, the diagnostic was displaying the code for the TCM which was not one of the initial 29 codes present in the previous visit. This also lasted about 48 hours before the problem occurred again, so I brought it in a third time and they disconnected everything from the BCM and reconnected it all to ensure that everything was secure from the previous repair. The diagnostic code for this visit was once again, the TCM.
Driving home today, the issue occurred and I hadn't even had the car back in my possession for a full 16 hours at this point. They have checked the alternator, spark plugs, battery, battery cables, valves for leaks, some of the door wiring associated with my master lock and window controls, wires, and reconnected the BCM after a full replacement.
They are now wanting me to pay $1340 for a TCM replacement, but at this point, I don't even feel confident that they know what the issue is and I'm reluctant to spend another large amount of money if the issue is still mostly of an unknown cause. I've checked several forums and it seems that while this issue occurs in a variety of Chevy models, there wasn't one I saw with a definitive solution or update. Has anyone experienced something like this? What did you do or what do you recommend?
Thank you!
In the past two-ish months, occasionally while driving, the car locks would go up and down a few times and while this is happening, the car would put itself into what felt like neutral. I'd be in stop-and-go traffic revving unable to move for about 2 to 3 seconds. In the past 3 weeks, this has escalated from being infrequent to happening almost every time I'd use the car. It began to go from a "quirk" to feeling really really unsafe, so last week I brought it into my usual mechanic. No warning lights were on, but even simply starting the car would cause the locks to "freak out" if that makes any sense, and the indicator for the gear I'm in would flutter displaying reverse, drive, neutral, etc.
Their first diagnostic scan indicated 29 codes in the BCM so I got the BCM replaced (inc. labor) for $1212. Within a day and a half, the issue happened again, so I re-brought it in and they examined the battery cables and gave me a new battery ($289). At this visit, the diagnostic was displaying the code for the TCM which was not one of the initial 29 codes present in the previous visit. This also lasted about 48 hours before the problem occurred again, so I brought it in a third time and they disconnected everything from the BCM and reconnected it all to ensure that everything was secure from the previous repair. The diagnostic code for this visit was once again, the TCM.
Driving home today, the issue occurred and I hadn't even had the car back in my possession for a full 16 hours at this point. They have checked the alternator, spark plugs, battery, battery cables, valves for leaks, some of the door wiring associated with my master lock and window controls, wires, and reconnected the BCM after a full replacement.
They are now wanting me to pay $1340 for a TCM replacement, but at this point, I don't even feel confident that they know what the issue is and I'm reluctant to spend another large amount of money if the issue is still mostly of an unknown cause. I've checked several forums and it seems that while this issue occurs in a variety of Chevy models, there wasn't one I saw with a definitive solution or update. Has anyone experienced something like this? What did you do or what do you recommend?
Thank you!
