GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Driver Seat Schematics Passenger Seat Schematics

Connector End View Reference: Power Seat Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Start the engine.
  2. Attempt to operate the heated seat in all of the operating modes.

Does the system operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Install a scan tool.
  2. Observe the Back Only Heat Switch parameter in the door module Inputs data list.
  3. Press and release the back only heated seat switch.

Does the scan tool display Active while the switch is pressed?

Go to Step 4

Go to Step 8

4

  1. Observe the Heated Seat Switch parameter in the door module Inputs data list.
  2. Press and release the back and cushion heated seat switch.

Does the scan tool display Active while the switch is pressed?

Go to Step 5

Go to Step 8

5

  1. Display the Seat Heat Zone parameter in the seat module Inputs/Outputs data list.
  2. Operate the heated seat switches in all of the operating modes.

Does the scan tool display the correct seat heat zone parameter in relation to the heated seat switch operation?

Go to Step 6

Go to Step 9

6

  1. Disconnect the inoperative seat heater element connector.
  2. Connect a test lamp between the voltage supply circuit terminal and the control circuit terminal in the harness connector.
  3. Operate the appropriate heated seat switch to the high mode.

Does the test lamp illuminate?

Go to Step 10

Go to Step 7

7

Test the seat heater element voltage supply and control circuits in the seat harness for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs .

Did you find and correct the condition?

Go to Step 14

Go to Step 9

8

Inspect for poor connections at the harness connector of the door module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs.

Did you find and correct the condition?

Go to Step 14

Go to Step 11

9

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

Did you find and correct the condition?

Go to Step 14

Go to Step 12

10

Inspect for poor connections at the harness connector of the inoperative seat heater element. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

11

Replace the door module. Refer to Control Module References for replacement, setup, and programming.

Is the repair complete?

Go to Step 14

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12

Replace the seat module. Refer to Control Module References for replacement, setup, and programming.

Is the repair complete?

Go to Step 14

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13

Replace the inoperative seat heater element. Refer to Front Seat Cushion Cover and Pad Replacement or to Front Seat Back Cushion Cover and Cushion Pad Replacement.

Is the repair complete?

Go to Step 14

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14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2