GM Service Manual Online
For 1990-2009 cars only

Step

Action

Values

Yes

No

Schematic Reference: Driver Seat Schematics and Passenger Seat Schematics

Connector End View Reference: Power Seat Connector End Views

1

Did you review the Heated Seat System Description and Operation and perform the necessary inspections?

--

Go to Step 2

Go to Heated Seats Description and Operation

2

  1. Turn ON the ignition.
  2. Operate the heated seat switch in the high, low, and OFF switch positions.

Does the Heated Seat System operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Does the heated seat switch indicator operate normally?

--

Go to Step 6

Go to Step 4

4

  1. Disconnect the heated seat switch harness connector.
  2. Connect a test lamp between the ignition voltage circuit in the harness connector and a good ground.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 21

5

Connect a test lamp between the ignition voltage circuit and the ground circuit in the heated seat switch harness connector.

Does the test lamp illuminate?

--

Go to Step 25

Go to Step 22

6

  1. Disconnect the heated seat module harness connector.
  2. Connect a test lamp between the battery positive voltage circuit in the harness connector and a good ground.

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 23

7

Connect a test lamp between the battery positive voltage circuit and the ground circuit in the heated seat module harness connector.

Does the test lamp illuminate?

--

Go to Step 8

Go to Step 24

8

  1. Connect a test lamp between the heated seat switch signal circuit in the heated seat module harness connector and ground.
  2. Operate the heated seat switch in the high and low positions.

Does the test lamp illuminate in the high and low switch positions?

--

Go to Step 9

Go to Step 10

9

  1. Turn the ignition OFF.
  2. Measure the resistance between the heated seat switch high/low signal circuit and the heated seat switch signal circuit in the heated seat module harness connector.
  3. Operate the heated seat switch in the high and low switch positions.

Does the resistance measure within the specified range?

High 100-1000

Low 2.0-3.0k

Go to Step 12

Go to Step 11

10

Test the heated seat switch signal circuit for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 33

Go to Step 25

11

Test the heated seat high/low signal circuit for the following conditions:

    • An open
    • A short to ground
    • A short to voltage

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 33

Go to Step 25

12

Measure the resistance between the heated seat element temperature signal circuit and the ground circuit in the heated seat module harness connector.

Does the resistance measure within the specified range?

6-12 kΩ

Go to Step 13

Go to Step 16

13

Measure the resistance between the heated seat element supply voltage circuit and the ground circuit in the heated seat module harness connector.

Does the resistance measure within the specified range?

0.5-5 Ω

Go to Step 28

Go to Step 14

14

  1. Disconnect the seat cushion heater element connector.
  2. Measure the resistance between the terminals of the seat cushion heating element connector.

Does the resistance measure within the specified range?

0.5-2 Ω

Go to Step 15

Go to Step 26

15

  1. Disconnect the seat back heater element connector.
  2. Measure the resistance between the terminals of the seat back heating element connector.

Does the resistance measure within the specified range?

0.5-2 Ω

Go to Step 18

Go to Step 27

16

Test the signal circuit between the heated seat module and the heated seat temperature sensor for the following conditions:

    • A short to ground
    • A high resistance
    • An open

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 33

Go to Step 17

17

Test the ground circuit between the heated seat temperature sensor and the heated seat module for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 33

Go to Step 26

18

Test the supply voltage circuit between the heated seat module and the seat cushion heating element for the following conditions:

    • A short to ground
    • A high resistance
    • An open

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 33

Go to Step 19

19

Test the supply voltage circuit between the seat cushion and the seat back heating element for the following conditions:

    • A short to ground
    • A high resistance
    • An open

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 33

Go to Step 20

20

Repair the high resistance or open in the ground circuit between the seat back heating element and the heated seat module. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 33

--

21

Repair the short to ground or open in the ignition voltage circuit of the heated seat switch. Refer to Wiring Repairs .

Did you complete the repair?

--

Go to Step 33

--

22

Repair the high resistance or open in the ground circuit heated seat switch. Refer to Wiring Repairs .

Did you complete the repair?

--

Go to Step 33

--

23

Repair the short to ground or open in the battery positive voltage circuit of the heated seat module. Refer to Wiring Repairs .

Did you complete the repair?

--

Go to Step 33

--

24

Repair the high resistance or open in the ground circuit of the heated seat module. Refer to Wiring Repairs .

Did you complete the repair?

--

Go to Step 33

--

25

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

Did you find and correct the condition?

--

Go to Step 33

Go to Step 29

26

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

Did you find and correct the condition?

--

Go to Step 33

Go to Step 31

27

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

Did you find and correct the condition?

--

Go to Step 33

Go to Step 32

28

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

Did you find and correct the condition?

--

Go to Step 33

Go to Step 30

29

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

Is the repair complete?

--

Go to Step 33

--

30

Replace the heated seat module. Refer to Front Seat Heater Control Module Replacement .

Is the repair complete?

--

Go to Step 33

--

31

Replace the seat cushion heater element/temperature sensor. Refer to Driver or Passenger Seat Cushion Heater Replacement .

Is the repair complete?

--

Go to Step 33

--

32

Replace the seat back heater element. Refer to Driver or Passenger Seat Back Cushion Heater Replacement .

Is the repair complete?

--

Go to Step 33

--

33

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2