Trailblazer, 2019, 30,000km, fully serviced, towing a 2.8T caravan.
A very odd thing happened today (10-Dec-2021); I was about 50km into a 200km trip towing my caravan on a long, straight, flat bitumen road in central Victoria. Conditions were daylight, dry, moderate wind, 23C, speed 85kph, transmission oil at 88C, 2WD, no cruise control - situation normal on all counts.
Abruptly a significant noise developed; I thought the gearbox had fallen apart or the driveshaft broken, something mechanical and major anyway. So foot off throttle and gently onto brake, usually the brake pedal has 25mm or so of free travel before the brakes start to work, not this time! Instead the pedal was hard and resistive as soon as I touched it and I could feel a pulsing from it through my foot. The noise and pulsing pedal lasted about three seconds.
I came to a safe stop; no warning lights on the cluster, no message on the display - all normal. I got out checked everything on both car and caravan even got down on my knees with a torch to check underneath - nothing. I drove the vehicle slowly for about 100m, all good no issues or warnings. I continued my journey under normal driving conditions and arrived safely. No repeat of the problem, no warnings on the cluster.
I *think* the ABS activated, for reasons best known to itself, which would account for both the noise and the brake pedal feedback and I can only assume this was caused by a software bug as I imagine a faulty wheel rotation sensor would be flagged as an error given I was not braking at the time. Having written real-time automotive software I am not unfamiliar with such matters. In a day or two I'll connect an OBDII dongle and Torque and see if any error codes have been generated. I'm sure the incident will have been logged but it may need OEM tools to read such data.
The only thing which has changed recently is that I had one rear tyre replaced and the spare swapped onto the other rear wheel about two weeks past and I've covered around 200km since without issue.
Mainly, I want to log this issue to the internet in case it's more than a one-off.
Mike_Harding@gmx.us
__________________
"I beseech you in the bowels of Christ think it possible you may be mistaken"
Oliver Cromwell, 3rd August 1650 - in a letter to the General Assembly of the Kirk of Scotland
Never had that issue with mine. Hopefully I don't and you never will again.
I was on the Trailblazer forum for a while and don't recall ever reading about that issue. I left the group after one too many stupid questions asked by morons...couldn't help myself with a response and was howled down by the goodie two shoes on there who were too gutless to tell the idiot that posted that he was too stupid to own a car.
