There is a way to open the cover manually. I am sorry I did not get it to you sooner.
I hope this helps you. If so, please ACCEPT this answer. I will be glad to help further if needed.
To open the cover Manually:
If an electrical or battery failure
happens, your vehicle is equipped
with a manual release lever that can
open the tonneau cover.
1. To open, locate the manual
release lever under the right front
corner of the pickup box.
2. Using the ignition key, unlock the
cover and pull the lever down to
manually open the tonneau cover.
3. Push the tonneau cover up for
access to the pickup box.
4. To close, push the tonneau cover
down on the pickup box until it
I guess I misunderstood your question. Here are some possible causes of the failure.
The tonneau cover switch sends a ground signal to the tonneau cover module through circuits 1628 (WH/RD) to open and 1629 (PK/LG) /1631 (PK) to close. The tonneau cover module then checks these inputs for these conditions:
The tonneau cover module will then apply power and ground to the appropriate tonneau cover motor circuits and tonneau cover motor clutch circuits. The tonneau cover module then checks input from the tonneau cover sense circuits, 1617 (WH/LG) and circuit 1618 (WH/BK) to verify the motor is operating in the correct direction and to detect obstacles.
There is a lengthy pinpoint test associated with the failure. It does somewhat require the use of a scan tool capable of communicating with the module.
I can give you a basic wiring diagram or the pinpoint test if you would like.
Thanks, Tim. Wow, obviously more than I care to dig into myself. I'll accept your answer and thank you for your time.
You are very welcome. Thank you.