GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Driver Seat Schematics and 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 in Vehicle DTC Information

2

Operate the Heated Seat System.

Does the system operate normally?

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

Go to Step 3

3

  1. Install a scan tool.
  2. Start the engine.
  3. Display the Heated Seat Status and Zone parameters in the driver seat module (DSM) Input/Output data list.
  4. Operate the heated seat switch in all modes.

Does the scan tool display the correct Heated Seat parameters in relation to heated seat switch operation?

Go to Step 8

Go to Step 4

4

  1. Display the Heated Seat Switch parameters in the door module Inputs data list.
  2. Press the head seat switches while observing the scan tool parameters.

Does the scan tool display the heated seat switches as active while the switches are pressed?

Go to Step 5

Go to Step 6

5

Do the heated seat switch indicators operate normally?

Go to Step 13

Go to Step 12

6

  1. Disconnect the heated seat switch harness connector to the door module.
  2. Test the resistance through the heated seat switch from the voltage supply circuit terminal to the back only select switch signal circuit terminal while operating the heat level switch.

Does the back only select switch have continuity only when pressed?

Go to Step 7

Go to Step 10

7

Test the resistance through the heated seat switch from the voltage supply circuit terminal to the back/cushion select switch signal circuit terminal while operating the back/cushion select switch.

Does the back/cushion select switch have continuity only when pressed?

Go to Step 12

Go to Step 10

8

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

Does the test lamp illuminate?

Go to Step 11

Go to Step 9

9

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

Did you find and correct the condition?

Go to Step 18

Go to Step 13

10

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

Did you find and correct the condition?

Go to Step 18

Go to Step 14

11

Inspect for poor connections at the heated seat element connector. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 15

12

Inspect for poor connections at the door module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 16

13

Inspect for poor connections at the DSM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 18

Go to Step 17

14

Replace the heated seat switch. Refer to Front Seat Heater Switch Replacement .

Is the repair complete?

Go to Step 18

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15

Replace the inoperative heated seat element. Refer to Driver Seat and Passenger Seat Back Cushion Heater Replacement or to Driver Seat and Passenger Seat Cushion Heater Replacement .

Is the repair complete?

Go to Step 18

--

16

Replace the door module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Is the repair complete?

Go to Step 18

--

17

Replace the DSM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Is the repair complete?

Go to Step 18

--

18

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3