Bulletin No.: PIT5550C
Published date: 10/28/2019

Preliminary Information
PIT5550C Left Side Third Row Seat will not Power Fold/Unfold or
Moves One Inch at a Time
Models
Brand:

Model:

Model Years:

VIN:
from

Engine:

to

Transmissions:

Cadillac

Escalade

2015 - 2020

All

All

All

All

Chevrolet

Tahoe

2015 - 2020

All

All

All

All

Chevrolet

Suburban

2015 - 2020

All

All

All

All

GMC

Yukon

2015 - 2020

All

All

All

All

Involved Region or
Country

North America (Including North American Export Regions)

Additional Options
(RPO)

AS8 - Power folding third row seat

Condition

Some customers may comment the left side third row seat will not
power fold or unfold, or may move one inch at a time. They may also
comment when pressing the third row folding seat switch they can
hear the seat unlatch then latch with no seat movement. No DTC will
be set for these concerns. This concern may be affected by
temperature or may show up after a hot or cold soak.
These concerns could be caused by an intermittent missing hall
effect position sensor input to the third row folding seat control
module.

Cause

When pressing the third row folding seat switch in either direction
the following sequence of events will occur during normal operation;
- Third row folding seat control module will unlatch the seat back.
- Seat back motor is driven in the desired direction while the third
row seat module is monitoring the input from the hall effect
position sensor.
- Once the folding seat switch is released in the desired position,
the seat back motor then stops.
- The third row seat module then latches the seat to lock the seat
back into position.
- The module then verifies the seat back is latched by trying to drive
the seat back motor while the seat is latched.
If the third row folding seat module does not see an input from the
hall effect sensor when it is trying to drive the seat back motor, the
module will think the seat back is in a stalled situation. In
this scenario the module will turn off the seat fold motor control,
latch the seat back into position, and then verify it is latched.

Correction:
If normal SI diagnostics does not lead to a correction, check for open circuits between the
third row folding seat control module and the hall effect sensor which is located within the
folding seat drive motor. If open circuits are found, one common area to check for broken
wires is about 6 inches away (2) from the third row K169 power folding seat control module
(1).

The circuits may be broken internally in the insulation and may not be physically visible.
A pull test on the circuits to see if they stretch may help in diagnosing the location of the
open in the circuit.
If a concern is found, repair the circuits as necessary and evaluate operation.
It is recommended to replace the entire circuit, or the harness if necessary, if the break is
found where the harness flexes (2) when the seat is folding/unfolding.

If a customer experiences this concern with the seat locked in the folded or unfolded
position and they need to use the 3rd row power seat in the opposite position, damage may
occur to the drive motor bracket and/or the seatback frame if the 3rd row power seat is
manually forced to the opposite position, as there is no manual override function.
Inspect the 3rd row power seat frame and motor bracket to ensure no damage is present
(See illustrations below).

Example of in-tact frame shown above.

Example of damaged frame shown above.

Version History
Version

Modified

4
02/28/2017 Created on
05/01/2017 Updated to add pictures of damaged seat back and
drive motor bracket
10/29/2018 Updated Model Years
10/28/2019 Update Model Years

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