GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Has the Lumbar Support System Check been performed?

--

Go to Step 2

Go to Lumbar Support System Check

2

  1. Access the lumbar support switch.
  2. Connect a DMM between CKT 640 (ORN), w/o heated seats or CKT 540 (ORN), w/heated seats, and ground.

Is there battery voltage?

--

Go to Step 3

Go to Step 9

3

  1. Connect a DMM between CKT 767 (RED) and ground.
  2. Toggle the lumbar support switch to the inflate position.

Is there battery voltage?

--

Go to Step 4

Go to Step 10

4

  1. Connect a DMM between CKT 768 (GRY) and ground.
  2. Toggle the lumbar support switch to the inflate position.

Is there battery voltage?

--

Go to Step 5

Go to Step 10

5

  1. Access power lumbar support motor and solenoid assembly.
  2. Connect a DMM between CKT 150 (BLK) and ground at the lumbar solenoid.

Is there continuity?

--

Go to Step 6

Go to Step 11

6

  1. Connect a DMM between CKT 767 (RED) at the lumbar motor and ground.
  2. Toggle the lumbar support switch to the inflate position.

Is there battery voltage?

--

Go to Step 7

Go to Step 12

7

  1. Connect a DMM between CKT 768 (ORN) at lumbar solenoid and ground.
  2. Toggle the lumbar support switch to the inflate position.

Is there battery voltage?

--

Go to Step 8

Go to Step 13

8

Replace the lumbar support motor and solenoid assembly. Refer to Lumbar Pump Replacement .

Is the repair complete?

--

Go to Lumbar Support System Check

--

9

Repair open in CKT 640 (ORN), w/o heated seats, or CKT 540 (ORN), w/heated seats between lumbar support switch and I/P fuse block. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Lumbar Support System Check

--

10

Replace the lumbar support switch. Refer to Lumbar Switch Replacement .

Is the repair complete?

--

Go to Lumbar Support System Check

--

11

Repair open in CKT 150 (BLK) between the lumbar support motor and solenoid assembly and G202. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Lumbar Support System Check

--

12

Repair open in CKT 767 (RED) between lumbar support switch and lumbar support motor and solenoid assembly. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Lumbar Support System Check

--

13

Repair open in CKT 768 (GRY) between lumbar support switch and lumbar support motor and solenoid assembly. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Lumbar Support System Check

--