Bulletin No.: PIC6622

Service Bulletin

Date: October, 2025

PRELIMINARY INFORMATION
Subject:
Brand:

Folding Top Inoperative - Erratic Operation
Model:

Model Year:
from

Chevrolet

Corvette

VIN:
to

2024 - 2026

from
All

Engine:

Transmission:

to
All

All

All

Involved Region or Country

North America

Additional Options (RPO)

CM9 - Power Retractable Hard Top W/ Remote Activation (down only).

Condition

Some customer's may comment about an inoperative folding top on their vehicle. Others
may comment about intermittent, or erratic operation from the folding top. This concern
may be accompanied by any folding top or CAN bus related DTCs. The following DTCs
may be set, but not limited to: B19EA, B1A51, B19E0, B19E1, B19E7, B19E8, U1105,
U1106, U1107, U1108 and/or a U0079. The Folding Top Module power supply fuses
F23RA, F24RA, F25RA, or the F26RA may be open as well.

Cause

Copyright 2025 General Motors. All Rights Reserved.

This concern may be caused by a broken wiring harness on either the RH or the LH side
rail of the folding top system. The general location of this concern may be found in
between the roof panels, when the linkage folds in half as seen in the photos below.
Zoomed out view showing the hinge location of the possible broken wiring harness.

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October, 2025

Bulletin No.: PIC6622

7005159

Zoomed in view of the same location showing actual wiring damage.

Bulletin No.: PIC6622

October, 2025

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7005160

If any of the symptoms mentioned above are encountered, if no other obvious concerns
are found, dealership technicians are to move the folding top up and down using the
interior switch on the driver's door panel. See if the operation of the folding top system
changes when the roof is in various positions during it's travel. In many instances, the top
will work perfectly fine for part of it's travel. When it gets to one certain location however,
depending on which circuit(s) may be damaged, the top may stop working all together, or
it may start to operate in an erratic motion. Techs may find DTCs set or they may find
that even the entire CAN 4 bus will stop communicating.

Correction
If any of these symptoms are experienced, dealership technicians are to closely inspect the wiring harness that runs
fore/aft along the LH and the RH main folding top side rails. The wiring harness can become pinched in either side
rail on the folding top.
Note: Because of the armor tape and/or convoluted tubing that is used to cover the various locations of wiring
harness on this folding top, dealership technicians may be required to remove the tubing and cut open the armor
tape to physically inspect the condition of the wiring harness inside this protective layer. In many instances it is found
that no damage whatsoever will be seen to the outer shield, but when peeled back, clear damage to the wiring
circuits has been found.
If any wiring / harness damage is found, repair the circuit(s) as needed.

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October, 2025

Bulletin No.: PIC6622

Warranty Information
The correction for this concern may be one of several repairs described in the diagnostic tips above, for vehicles
repaired under warranty please use the appropriate warranty labor operation based on the actual cause and repair.
Version

1

Modified

10/08/25 Created on.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job
properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.

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