B-52

On my 2023 the remote control function / button push sequence does not open the HTC tonneau cover .
The remote appears to work normally with other functions. Car battery is fully charged.
is there a factory reset function on the C8 ? Should I try simply disconnecting the battery and reconnecting ?
Any thoughts/experience with this issue?

Andybump

Are you trying to open it in service mode? Where is the top when you do this? To open in service mode the top needs to be up/closed. That is a frequent error. The trunk must be closed as well. It does not say, but you might check that doors and the funk are close though I do not know if that is an issue. Other than that, just remote lock the car, then press and hold the top button on the fob. If its not working there is an issue. You can try the resets you mentioned.

MarkMeHopeful

What Andy said - For service mode: Top up, doors closed, trunk closed, press lock button on the fob, then press and hold the top button.

To lower the top, Top up, doors closed, trunk closed, press unlock button on the fob, then press and hold the top button.

The tonneau cover won't raise with the fob if the top is already down.

RandelB

...everything said so far. Emphasize that the top button needs to be pressed and held continuously throughout the entire cycle. Also, the response is not immediate when you press the top button...a few seconds delay.

From '22 owner's manual

B-52

Solved . Strangely I tried the second key fob and it worked as expected . Even though the problem first fob seemed to work all other functions I decided to replace the fob battery.
Voila it works as advertised. Replaced the battery in the other as well.
Continuously amazed at how sensitive new cars are to the slightest voltage issues.

cajunboyz

Good to Know