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For 1990-2009 cars only

Lumbar Support Inoperative w/o A45

Step

Action

Value(s)

Yes

No

SCHEMATIC REFERENCE: Lumbar Support Schematics

1

Did you review the power seat operation and perform the necessary inspection?

--

Go to Step 2

Go to Symptoms

2

Measure the voltage from the battery positive voltage circuit of the lumbar switch to a good ground.

Does the voltage measure within the specified range?

9-16 V

Go to Step 3

Go to Step 5

3

Measure the voltage from the battery positive circuit of the lumbar switch to the ground circuit of the lumbar switch.

Does the voltage measure within the specified range?

9-16 V

Go to Step 4

Go to Step 6

4

Inspect for poor connections at the harness connector of the lumbar switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 8

Go to Step 7

5

Repair the open in the battery positive voltage circuit of the lumbar switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 8

--

6

Repair the open in the ground circuit of the lumbar switch.

Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 8

--

7

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

Did you complete the replacement?

--

Go to Step 8

--

8

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Lumbar Support Inoperative with A45

Step

Action

Value(s)

Yes

No

SCHEMATIC REFERENCE: Lumbar Support Schematics

1

Did you perform the Diagnostic System Check - Power Seat Systems?

--

Go to Step 2

Go to Diagnostic System Check - Power Seat Systems

2

Measure the voltage from the battery positive voltage circuit of the lumbar switch to a good ground.

Does the voltage measure within the specified range?

9-16 V

Go to Step 3

Go to Step 6

3

Did the seat lumbar move when a memory recall function was performed?

--

Go to Step 4

Go to Step 5

4

Inspect for poor connections at the harness connector of the lumbar switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 7

5

Inspect for poor connections at the harness connector of the memory seat module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

9-16 V

Go to Step 9

Go to Step 8

6

Repair the open in the battery positive voltage circuit of the lumbar switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 9

--

7

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

Did you complete the replacement?

--

Go to Step 9

--

8

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

Did you complete the replacement?

--

Go to Step 9

--

9

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Lumbar Support Inoperative with AC9

Step

Action

Value(s)

Yes

No

SCHEMATIC REFERENCE: Lumbar Support Schematics

1

Did you review the power seat operation and perform the necessary inspection?

--

Go to Step  2

Go to Symptoms

2

Verify the customer complaint.

Does the system operate as described in the system description and operation?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step  3

3

  1. Disconnect the adaptive lumbar module harness connector.
  2. Turn ON the ignition, with the engine OFF.
  3. Connect a test lamp between the battery positive voltage (B+) circuit of the adaptive lumbar module connector and a good ground.

Does the test lamp illuminate?

--

Go to Step  4

Go to Step  18

4

Connect a test lamp between the ignition 3 circuit of the adaptive lumbar module connector and a good ground.

Does the test lamp illuminate?

--

Go to Step  5

Go to Step  17

5

Connect a test lamp between the ignition 3 circuit of the adaptive lumbar module connector and the ground circuit of the module connector.

Does the test lamp illuminate?

--

Go to Step  6

Go to Step  19

6

Connect a test lamp from battery positive voltage (B+) to each lumbar switch signal circuit of the adaptive lumbar module connector.

Does the test lamp illuminate on any of the circuits?

--

Go to Step  11

Go to Step  7

7

  1. Connect a test lamp between battery positive voltage (B+) and the auto/on signal circuit of the adaptive lumbar module connector.
  2. Activate the lumbar switch in the AUTO/ON direction.

Does the test lamp illuminate?

--

Go to Step 8

Go to Step  12

8

  1. Connect a test lamp between battery positive voltage (B+) and the off/down signal circuit of the adaptive lumbar module connector.
  2. Activate the lumbar switch in the OFF/DOWN direction.

Does the test lamp illuminate?

--

Go to Step 9

Go to Step  13

9

  1. Connect a test lamp between battery positive voltage (B+) and the lumbar back signal circuit of the adaptive lumbar module connector.
  2. Activate the lumbar switch in the BACK direction.

Does the test lamp illuminate?

--

Go to Step 10

Go to Step  13

10

  1. Connect a test lamp between battery positive voltage (B+) and the lumbar forward signal circuit of the adaptive lumbar module connector.
  2. Activate the lumbar switch in the FORWARD direction.

Does the test lamp illuminate?

--

Go to Step 14

Go to Step  13

11

Test the appropriate lumbar switch signal circuit between the adaptive lumbar module and the lumbar switch for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  22

Go to Step 15

12

Test the ground circuit of the lumbar switch for a high resistance or an open.

Did you find and correct the condition?

--

Go to Step  22

Go to Step 13

13

Test the appropriate lumbar switch signal circuit between the adaptive lumbar module and the lumbar switch for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  22

Go to Step  15

14

Perform a mechanical inspection of the adaptive lumbar module and bladders for air leaks, pinched air lines, and a blocked exhaust port.

Did you find and correct the condition?

--

Go to Step  22

Go to Step 16

15

Inspect for poor connections at the harness connector of the lumbar switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  22

Go to Step  20

16

Inspect for poor connections at the harness connector of the adaptive lumbar module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  22

Go to Step  21

17

Repair the open or short to ground in the IGN 3 circuit of the adaptive lumbar module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step  22

--

18

Repair the open or short to ground in the battery positive voltage (B+) circuit of the adaptive lumbar module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step  22

--

19

Repair the open in the ground circuit of the adaptive lumbar module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step  22

--

20

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

Did you complete the replacement?

--

Go to Step  22

--

21

Replace the adaptive lumbar module. Refer to Front Seat Lumbar Support Replacement .

Did you complete the replacement?

--

Go to Step  22

--

22

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step  2