Circuit/System Testing: Notes

WARNING: This page is about a different car, the 2010 GMC Terrain and 2010 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.

B3920 01 or B3920 02

Ignition OFF, disconnect the X4, X5 harness connectors at the K40 seat memory control module.
Test for infinite resistance between the control circuit terminals listed below and ground:
- M50D front vertical motor up control terminal 7 X4
- M50D front vertical motor down control terminal 8 X4
- M55D rear vertical motor up control terminal 4 X5
- M55D rear vertical motor down control terminal 3 X5
- M51D horizontal motor forward control terminal 2 X5
- M51D horizontal motor rearward control terminal 1 X5
- M56D recline motor forward control terminal 5 X5
- M56D recline motor rearward control terminal 6 X5
- If not the specified value, test the control circuit for a short to ground.
Ignition ON, verify that a test lamp does not illuminate between the control circuit terminals listed below and ground:
- M50D front vertical motor up control terminal 7 X4
- M50D front vertical motor down control terminal 8 X4
- M55D rear vertical motor up control terminal 4 X5
- M55D rear vertical motor down control terminal 3 X5
- M51D horizontal motor forward control terminal 2 X5
- M51D horizontal motor rearward control terminal 1 X5
- M56D recline motor forward control terminal 5 X5
- M56D recline motor rearward control terminal 6 X5
- If the test lamp illuminates, test the control circuit for a short to voltage.
If all circuits test normal, replace the K40 seat memory control module.

B3920 0B

Ignition ON, use a scan tool to clear the current and history DTC.
Determine which motor set this DTC by operating the driver seat motors listed below one at a time in both directions. Check for the DTC to set between each motor test.
- M50D seat front vertical motor
- M55D seat rear vertical motor
- M51D seat horizontal motor
- M56D seat back recline motor
Clear the diagnostic trouble code.
Ignition OFF, disconnect the harness connector at the appropriate seat motor for which the DTC set.
Ignition ON, operate the appropriate motor adjuster switch in both directions. DTC B3920 00 or B3920 0B should not set.
- If the DTC sets, test for a short between control circuits terminal 1 and terminal 5. If the circuits test normal, replace the K40 seat memory control module.
Test control circuits terminal 1 and terminal 5 for a high resistance. If the circuits test normal, test or replace the seat motor.