Rich Steel
CCCUK Member
On our way home from the Lakes, a truck pulled in front of me on the motorway and a sizeable rock (and other debris) flew off it and hit my windscreen. I wanted to check-out video from the PDR (which I have set to auto-record) when I got home, but when I tried to load it just got a blank screen. I removed the SD card to check its contents and found that, on our previous day's trip out to the Lakeland Museum, the PDR had carried-on recording all the time we were parked at the museum, and had continued for a further 23 minutes on the journey home until it abruptly stopped.
With the help of AI (scares me no end, but use it just the same!) I found this was likely a software glitch...
Modern GM vehicles use a communication network (CAN bus) to manage power states. When you shut off the car and open the door:
The recommended actions were to check the SD card was error-free/ had no corrupt files. (It was fine, but I reformatted it anyway.) I disconnected the battery terminals and touched them together to drain the residual power stored in the vehicle's capacitors. "This forced every single computer module in your C8 to undergo a true 'cold boot' from a zero-power state."
This seems to have resolved the problem and the PDR is again working fine. It's the first time I've experienced this in three years of ownership, but I thought it may be worth reporting upon in case anyone else here has a similar experience.
With the help of AI (scares me no end, but use it just the same!) I found this was likely a software glitch...
Modern GM vehicles use a communication network (CAN bus) to manage power states. When you shut off the car and open the door:
- The Body Control Module (BCM) broadcasts a "Go to Sleep" command across the network.
- The infotainment screen received it and shut off successfully (which is why your screens were blank).
- However, the dedicated PDR hardware module (which physically sits separately up by your rearview mirror) missed or failed to process that network command.
- The reason it suddenly ended 23 minutes into your drive is due to the C8's battery management system:
When you started the car with a heavily drained battery, the vehicle's alternator immediately went into high-output charging mode. To protect vital engine systems and rapidly charge the 12V battery, the car's computer aggressively shuts down or drops voltage to non-essential accessories (called Load Shedding). About 23 minutes into the drive, the system likely cut accessory power or forced a background module restart to prioritize battery charging, which finally killed the stuck PDR loop.
The recommended actions were to check the SD card was error-free/ had no corrupt files. (It was fine, but I reformatted it anyway.) I disconnected the battery terminals and touched them together to drain the residual power stored in the vehicle's capacitors. "This forced every single computer module in your C8 to undergo a true 'cold boot' from a zero-power state."
This seems to have resolved the problem and the PDR is again working fine. It's the first time I've experienced this in three years of ownership, but I thought it may be worth reporting upon in case anyone else here has a similar experience.
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