GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Seville 🢒 Body and Accessories 🢒 Seats 🢒 Lumbar Support Does Not Move In or Out

Lumbar Support Does Not Move In or Out AL2

Step

Action

Value(s)

Yes

No

DEFINITION: This table diagnoses the lumbar support, in out inoperative (option AL2) in the driver's seat or in out inoperative (option AL2 and/or AM3) in the passenger seat.

1

Was the entire Lumbar Support System Check performed?

--

Go to Step 2

Go to Lumbar Support System Check

2
  1. Backprobe the lumbar switch connector with a DMM from cavity A (PNK) (LH) or (PNK/BLK) (RH) to ground.
  2. Move the lumbar switch to the IN position.

Is the voltage within the specified range?

10-15 V

Go to Step 3

Go to Step 4

3
  1. Backprobe the lumbar switch connector with a DMM from cavity F (DK BLU) to ground.
  2. Move the lumbar switch to the OUT position.

Is the voltage within the specified range?

10-15 V

Go to Step 5

Go to Step 4

4

Replace the lumbar switch. Refer to Lumbar Switch Replacement .

Is the lumbar switch replacement complete?

--

Go to Lumbar Support System Check

--

5
  1. Backprobe the lumbar horizontal motor connector with a DMM from cavity B (PNK/BLK) (LH) or (WHT) (RH) to ground.
  2. Move the lumbar switch to the IN position.

Is the voltage within the specified range?

10-15 V

Go to Step 6

Go to Step 8

6
  1. Backprobe the lumbar horizontal motor connector with a DMM from cavity A (WHT) to ground.
  2. Move the lumbar switch to the OUT position.

Is the voltage within the specified range?

10-15 V

Go to Step 7

Go to Step 9

7

Replace the lumbar horizontal motor. Refer to Front Seat Lumbar Support Replacement .

Is the lumbar horizontal motor replacement complete?

--

Go to Lumbar Support System Check

--

8

Repair the open in CKT 610 (WHT) (LH) or CKT 210 (WHT) (RH) between the lumbar switch and the lumbar horizontal motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Lumbar Support System Check

--

9

Repair the open in CKT 611 (DK BLU) (LH) or CKT 211 (WHT) (RH) between the lumbar switch and the lumbar horizontal motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Lumbar Support System Check

--

Lumbar Support Does Not Move In or Out A45

Step

Action

Value(s)

Yes

No

DEFINITION: This table diagnoses the lumbar support, in out inoperative (option A45 and/or AM3) in the driver's seat.

1

Was the entire Lumbar Support System Check performed?

--

Go to Step 2

Go to Lumbar Support 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 LIST.
  4. Move the lumbar switch to the IN position and then to the OUT position.

Does the scan tool indicate that the lumbar switch moves IN and OUT?

--

Go to Step 3

Go to Step 6

3
  1. Disconnect the driver lumbar horizontal motor.
  2. Connect a fused jumper from the battery positive voltage (B+) to one of the driver lumbar horizontal motor terminals.
  3. Connect a fused jumper from the other driver lumbar horizontal motor terminal to ground.

Does the motor run?

--

Go to Step 4

Go to Step 12

4
  1. Disconnect the memory seat module (MSM) connector C1.
  2. Disconnect the memory seat module (MSM) connector C2.
  3. Connect a DMM from the driver lumbar horizontal motor cavity B (PNK) to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 5

Go to Step 13

5

Connect a DMM from the driver lumbar horizontal motor cavity A (DK BLU) to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 8

Go to Step 14

6
  1. Disconnect the memory seat module (MSM) connector C2.
  2. Connect a DMM from the MSM connector C2 cavity C9 (DK BLU) to ground.
  3. Move the lumbar switch IN.

Is the voltage less than the specified range?

10-15 V

Go to Step 7

Go to Step 9

7
  1. Connect a DMM from the MSM connector C2 cavity C10 (YEL) to ground.
  2. Move the lumbar switch to the OUT position.

Is the voltage less than the specified range?

10-15 V

Go to Step 8

Go to Step 10

8

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

Is the MSM replacement complete?

--

Go to Lumbar Support System Check

--

9
  1. Disconnect the lumbar switch connector.
  2. Connect a DMM from the MSM connector C2 cavity C9 (DK BLU) to the lumbar switch connector cavity A (DK BLU).

Is the resistance less than the specified range?

5 ohms

Go to Step 11

Go to Step 15

10

Connect a DMM from the MSM connector C2 cavity C10 (YEL) to the lumbar switch connector cavity F (DK BLU).

Is the resistance less than the specified range?

5 ohms

Go to Step 11

Go to Step 16

11

Replace the lumbar switch. Refer to Lumbar Switch Replacement .

Is the lumbar switch replacement complete?

--

Go to Lumbar Support System Check

--

12

Replace the driver lumbar horizontal motor. Refer to Front Seat Lumbar Support Replacement .

Is the driver lumbar horizontal motor replacement complete?

--

Go to Lumbar Support System Check

--

13

Repair the open in CKT 610 (PNK) between the MSM and the driver lumbar horizontal motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Lumbar Support System Check

--

14

Repair the open in CKT 611 (DK BLU) between the MSM and the lumbar horizontal motor. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Lumbar Support System Check

--

15

Repair the open in CKT 1064 (DK BLU) between the lumbar switch and the MSM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Lumbar Support System Check

--

16

Repair the open in CKT 1065 (YEL) between the lumbar switch and the MSM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Lumbar Support System Check

--