EI08147 - Seat Inoperative or Intermittent (Engineering Information)

Some customers may comment that the driver or passenger seat may be inoperative or the operation may be intermittent. This condition may affect the fore/aft, up/down and/or recline positions.

GM Engineering is attempting to determine the cause of this condition. Engineering would like to receive diagnostic information from the technician prior to any repairs being made.

Document the following information on the repair order:

1. Does the vehicle currently exhibit the condition? Proceed with this bulletin only if the vehicle currently exhibits the customer's concern.
2. Document which seat is inoperative and which seat functions are inoperative (i.e. fore/aft, up/down, recline, all).
3. Is the vehicle equipped with RPO A45 -- Memory Seats?
4. Complete the appropriate diagnostic steps:

With A45 -- Memory Seats:

4.1.

With the ignition ON, observe the scan tool Memory Seat Module (MSM) seat switch parameters while pressing the appropriate seat switch. If the reading does not change between the specified values, proceed with Step 4.2 (Seat Adjuster Switch Circuit Test). If the reading changes value, refer to the Step 4.3 (Seat Adjuster Motor Circuit Test).

4.2.	Seat Adjuster Switch Circuit Test:

4.2.1.

With the ignition OFF, disconnect the harness connector at the seat adjuster switch.

4.2.2.

With the ignition ON, verify that a test lamp illuminates between the B+ circuit terminal E and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4.3.	Seat Adjuster Motor Test:

4.3.1.

With the ignition ON, command the appropriate seat motor in the up/down or forward/rearward directions with a scan tool. The test lamp should turn ON when commanding the Up and Down or Forward and Rearward states. If the test lamp remains OFF during either of the commands, test the control circuits for an open/high resistance.

4.3.2.

With the ignition OFF, disconnect the X3 harness connector at the MSM.

4.3.3.

With the ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 5 and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4.3.4.

With the Ignition OFF, connect the X3 harness connector at the memory seat module and disconnect the X1 harness connector at the appropriate seat adjuster motor.

4.3.5.

Connect a test lamp between control circuit terminal 1 and control circuit terminal 5.

4.3.6.

Disconnect and reconnect each connector. Verify seat operation after each connector disconnect/reconnect. Note on the repair order if any loose/poor connections were found and if so, which connector.

4.4.	Has the customer's concern been corrected? Proceed to Step 5.

Without A45 -- Memory Seats:

4.1.	With the ignition OFF, disconnect the harness connector at the seat adjuster switch.

4.2.	Test for less than 5 ohms between the ground circuit terminal B and ground. If greater than the specified range, test the ground circuit for an open/high resistance.

4.3.	With the ignition ON, verify that a test lamp illuminates between the B+ circuit terminal E and ground. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

4.4.	Connect a test lamp between control circuit terminal 1 and control circuit terminal 5.

4.5.	Verify that the test lamp illuminates while pressing the appropriate seat switch in both directions. If the test lamp does not illuminate for both directions, test the control circuits for a short to ground or an open/high resistance.

4.6.	Disconnect and reconnect each connector. Verify seat operation after each connector disconnect/reconnect. Note on the repair order if any loose/poor connections were found and if so, which connector.

4.7.	Has the customer's concern been corrected? Proceed to Step 5.

5. Contact the engineer listed below with the diagnostic information.

If the engineer is unavailable, leave a message with the following information:

If the engineer does not return the call within two hours, proceed with diagnosis and repair according to information found in SI.

For vehicles repaired under warranty, use: