GM Service Manual Online
For 1990-2009 cars only

Step

Action

Values

Yes

No

Schematic Reference: Heated Seats Schematics

Connector End View Reference: Power Seat Connector End Views

1

Did you perform the Power Seat Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Power Seat Systems

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 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 9

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 7

5

Do the heated seat switch indicators operate normally?

--

Go to Step 15

Go to Step 6

6

Do the heated seat switch indicators illuminate momentairly and turn off?

--

Go to Step 10

Go to Step 14

7

  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 8

Go to Step 12

8

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 14

Go to Step 12

9

  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 13

Go to Step 11

10

  1. Disconnect the seat heater element connectors.
  2. Using a DMM measure the resistance through the seat heater elements. Refer to Circuit Testing in Wiring Systems.

Are the measurements within the specified values?

1.5-5.5ohms

Go to Step 15

Go to Step 13

11

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 20

Go to Step 15

12

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 20

Go to Step 16

13

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 20

Go to Step 17

14

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 20

Go to Step 18

15

Inspect for poor connections at the driver seat module (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 20

Go to Step 19

16

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

Is the repair complete?

--

Go to Step 20

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17

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

Is the repair complete?

--

Go to Step 20

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18

Replace the door module. Refer to Door Lock and Side Window Switch Replacement - Driver Side or Door Lock and Side Window Switch Replacement - Passenger Side in Doors.

Is the repair complete?

--

Go to Step 20

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19

Replace the DSM. Refer to Memory Seat Control Module Replacement .

Is the repair complete?

--

Go to Step 20

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20

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3