GM Service Manual Online
For 1990-2009 cars only

Power Seat Does Not Tilt Forward without A45

Step

Action

Value(s)

Yes

No

1

Was the entire Power Seats System Check performed?

--

Go to Step 2

Go to Power Seats System Check

2

  1. Backprobe the seat switch connector with a DMM from cavity D (DK GRN) (LH) or cavity E (DK GRN) (RH) to ground.
  2. Move the front height switch UP.

Is the voltage within the specified range?

10-15 V

Go to Step 3

Go to Step 4

3

  1. Backprobe the seat switch connector with a DMM from cavity A (DK BLU) (LH) or cavity G (DK BLU) (RH) to ground.
  2. Move the front height switch DOWN.

Is the voltage within the specified range?

10-15 V

Go to Step 5

Go to Step 4

4

Replace the seat switch. Refer to Power Seat Switch Replacement .

Is the seat switch replacement complete?

--

Go to Power Seats System Check

--

5

  1. Backprobe the front height motor connector with a DMM from cavity A (DK GRN) (LH) or cavity A (DK GRN) (RH) to ground.
  2. Move the front height switch UP.

Is the voltage within the specified range?

10-15 V

Go to Step 6

Go to Step 8

6

  1. Backprobe the front height motor connector with a DMM from cavity B (DK BLU) (LH) or cavity B (DK BLU) (RH) to ground.
  2. Move the front height switch DOWN.

Is the voltage within the specified range?

10-15 V

Go to Step 7

Go to Step 9

7

Replace the front height motor. Refer to Front Seat Adjuster Replacement .

Is the front height motor replacement complete?

--

Go to Power Seats System Check

--

8

Repair the open in CKT 286 (DK GRN) (LH) or CKT 297 (DK GRN) (RH) between the seat switch and the front height motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Power Seats System Check

--

9

Repair the open in CKT 287 (DK BLU) (LH) or CKT 298 (DK BLU) (RH) between the seat switch and the front height motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Power Seats System Check

--

Power Seat Does Not Tilt Forward A45 with AL2

Step

Action

Value(s)

Yes

No

1

Was the entire Memory Seats System Check performed?

--

Go to Step 2

Go to Memory Seats System Check

2

  1. Turn the ignition switch to the ON position.
  2. Connect a scan tool to the data link connector (DLC).
  3. Select INPUTS from the memory seat module (MSM) DATA DISPLAY.
  4. Operate the LH seat front height switch in the UP direction.

Did the scan tool indicate that the seat switch input was received?

--

Go to Step 3

Go to Step 8

3

Operate the LH seat front height switch in the DOWN direction.

Did the scan tool indicate that the seat switch input was received?

--

Go to Step 4

Go to Step 9

4

  1. Disconnect the LH front height motor.
  2. Connect a fused jumper from battery positive voltage (B+) to one motor terminal.
  3. Connect a fused jumper from the other motor terminal to ground.

Did the motor run?

--

Go to Step 5

Go to Step 11

5

Check for an open or short to ground in CKT 286 (DK GRN) between the MSM and the LH front height motor.

Is CKT 286 OK?

--

Go to Step 6

Go to Step 12

6

Check for an open or short to ground in CKT 287 (DK BLU) between the MSM and the LH front height motor.

Is CKT 287 OK?

--

Go to Step 7

Go to Step 13

7

Replace the memory seat module (MSM). Refer to Memory Seat Control Module Replacement .

Is the MSM replacement complete?

--

Go to Memory Seats System Check

--

8

  1. Disconnect the LH seat switch connector.
  2. Disconnect the memory seat module (MSM) connector C2.
  3. Connect a DMM from the LH seat switch connector cavity D (DK GRN) to the MSM connector C2 cavity C1 (DK GRN).

Is the resistance less than the specified value?

5 ohms

Go to Step 10

Go to Step 14

9

  1. Disconnect the LH seat switch connector.
  2. Disconnect the memory seat module (MSM) connector C2.
  3. Connect a DMM from the LH seat switch connector cavity A (DK BLU) to the MSM connector C2 cavity C3 (DK BLU).

Is the resistance less than the specified value?

5 ohms

Go to Step 10

Go to Step 15

10

Replace the LH seat switch. Refer to Power Seat Switch Replacement .

Is the LH seat switch replacement complete?

--

Go to Memory Seats System Check

--

11

Replace the LH front height motor. Refer to Front Seat Adjuster Replacement .

Is the motor replacement complete?

--

Go to Memory Seats System Check

--

12

Repair the open or short to ground in CKT 286 (DK GRN) between the MSM and the LH front height motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--

13

Repair the open or short to ground in CKT 287 (DK BLU) between the MSM and the LH front height motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--

14

Repair the open in CKT 1518 (DK GRN) between the LH seat switch and the MSM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--

15

Repair the open in CKT 1520 (DK BLU) between the LH seat switch and the MSM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--

Power Seat Does Not Tilt Forward A45 with AC9

Step

Action

Value(s)

Yes

No

1

Was the entire Memory Seats System Check performed?

--

Go to Step 2

Go to Memory Seats System Check

2

  1. Turn the ignition switch to the ON position.
  2. Connect a scan tool to the data link connector (DLC).
  3. Select INPUTS from the memory seat module (MSM) DATA DISPLAY.
  4. Operate the LH seat front height switch in the UP direction.

Did the scan tool indicate that the seat switch input was received?

--

Go to Step 3

Go to Step 8

3

Operate the LH seat front height switch in the DOWN direction.

Did the scan tool indicate that the seat switch input was received?

--

Go to Step 4

Go to Step 9

4

  1. Disconnect the LH front height motor.
  2. Connect a fused jumper from battery positive voltage (B+) to one motor terminal.
  3. Connect a fused jumper from the other motor terminal to ground.

Did the motor run?

--

Go to Step 5

Go to Step 11

5

Check for an open or short to ground in CKT 286 (DK GRN) between the MSM and the LH front height motor.

Is CKT 286 OK?

--

Go to Step 6

Go to Step 12

6

Check for an open or short to ground in CKT 287 (DK BLU) between the MSM and the LH front height motor.

Is CKT 287 OK?

--

Go to Step 7

Go to Step 13

7

Replace the memory seat module (MSM). Refer to Memory Seat Control Module Replacement .

Is the MSM replacement complete?

--

Go to Memory Seats System Check

--

8

  1. Disconnect the LH seat switch connector.
  2. Disconnect the memory seat module (MSM) connector C2.
  3. Connect a DMM from the LH seat switch connector cavity D (DK GRN) to the MSM connector C2 cavity A1 (DK GRN).

Is the resistance less than the specified value?

5 ohms

Go to Step 10

Go to Step 14

9

  1. Disconnect the LH seat switch connector.
  2. Disconnect the memory seat module (MSM) connector C2.
  3. Connect a DMM from the LH seat switch connector cavity A (DK BLU) to the MSM connector C2 cavity A3 (DK BLU).

Is the resistance less than the specified value?

5 ohms

Go to Step 10

Go to Step 15

10

Replace the LH seat switch. Refer to Power Seat Switch Replacement .

Is the LH seat switch replacement complete?

--

Go to Memory Seats System Check

--

11

Replace the LH front height motor. Refer to Front Seat Adjuster Replacement .

Is the motor replacement complete?

--

Go to Memory Seats System Check

--

12

Repair the open or short to ground in CKT 286 (DK GRN) between the MSM and the LH front height motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--

13

Repair the open or short to ground in CKT 287 (DK BLU) between the MSM and the LH front height motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--

14

Repair the open in CKT 1518 (DK GRN) between the LH seat switch and the MSM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--

15

Repair the open in CKT 1520 (DK BLU) between the LH seat switch and the MSM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Memory Seats System Check

--