GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Heated Seats System Check?

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Go to Step 2

Go to Heated Seats System Check

2

  1. Disconnect the appropriate heated seat control module connector C1.
  2. Connect a J 39200 (DMM) from the heated seat module connector C1 cavity B (ORN) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 3

Go to Step 17

3

  1. Turn the ignition switch to RUN.
  2. Connect a J 39200 from the appropriate heated seat module connector C1 cavity A (BRN) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 4

Go to Step 18

4

  1. Turn the ignition switch to OFF.
  2. Connect a J 39200 from the appropriate heated seat module connector C1 cavity E (BLK) to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 5

Go to Step 19

5

Connect a J 39200 from the appropriate heated seat module connector C1 cavity B (ORN) to cavity H (YEL).

Is the voltage within the specified range?

10-15 V

Go to Step 6

Go to Step 26

6

  1. Press the appropriate heated seat switch.
  2. Connect a J 39200 from the appropriate heated seat module connector C1 cavity to ground:
  3. • LH: cavity C (PNK)
    • RH: cavity C (PNK/BLK)

Is the resistance less than the specified value?

5 ohms

Go to Step 10

Go to Step 7

7

Test the appropriate circuit for an open:

    • LH: CKT 1501 (PNK)
    • RH: CKT 1503 (PNK/BLK)

Refer to Testing for Continuity in Wiring Systems.

Is the circuit OK?

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Go to Step 8

Go to Step 28

8

Test CKT 450 (BLK) for an open between the appropriate heated seat switch and S217. Refer to Testing for Continuity in Wiring Systems.

Is there an open in CKT 450?

--

Go to Step 28

Go to Step 9

9

Replace the suspect heated seat switch.

Did you complete the repair?

--

Go to Step 28

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10

  1. Disconnect the appropriate heated seat control module connector C2.
  2. Disconnect the appropriate heated seat control module connector C3.
  3. Connect a J 39200 from the heated seat module connector C2 cavity A to cavity B.

Is the resistance less than the specified value?

10 ohms

Go to Step 11

Go to Step 20

11

Connect a J 39200 from the appropriate heated seat module connector C2 cavity A to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 21

Go to Step 12

12

Important: The thermistor resistance varies according to the temperature. Therefore, if you measure the resistance while the seat is still warm, the resistance may vary outside of the specified range.

With the seat at room temperature, connect a J 39200 from the appropriate heated seat module connector C2 cavity C to cavity D.

Is the resistance within the specified range?

850-1150 ohms

Go to Step 13

Go to Step 20

13

Connect a J 39200 from the appropriate heated seat module connector C2 cavity C to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 21

Go to Step 14

14

Connect a J 39200 from the appropriate heated seat module connector C3 cavity A to cavity B.

Is the resistance less than the specified value?

10 ohms

Go to Step 15

Go to Step 22

15

Connect a J 39200 from the appropriate heated seat module connector C2 cavity A to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 23

Go to Step 16

16

Replace the suspect heated seat module. Refer to Heater Module Replacement .

Is the repair complete?

--

Go to Step 29

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17

Repair the open or short to ground in the appropriate circuit between the rear fuse block and the heated seat module:

    • LH: CKT 1040 (ORN)
    • RH: CKT 1440 (ORN)

Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 29

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18

Repair the open or short to ground in CKT 241 (BRN) between the rear fuse block and the heated seat module. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 29

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19

Repair the open in CKT 450 (BLK) between the heated seat module and G201. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 29

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20

Test the appropriate seat cushion heating element wiring for an open. Refer to Testing for Continuity in Wiring Systems.

Is there an open in the seat cushion heating element?

--

Go to Step 28

Go to Step 24

21

Test the appropriate seat cushion element wiring for a short to ground. Refer to Testing for Short to Ground in Wiring Systems.

Is there a short to ground in the seat cushion heating element?

--

Go to Step 28

Go to Step 24

22

Test the appropriate seat back heating element for an open. Refer to Testing for Continuity in Wiring Systems.

Is there an open in the seat back heating element?

--

Go to Step 28

Go to Step 25

23

Test the appropriate seat back heating element wiring for a short to ground. Refer to Testing for Short to Ground in Wiring Systems.

Is there a short to ground in the seat back heating element wiring?

--

Go to Step 28

Go to Step 25

24

Replace the suspect seat cushion heating element. Refer to Front Seat Heater Element Replacement .

Is the repair complete?

--

Go to Step 29

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25

Replace the suspect seat back heating element. Refer to Front Seat Heater Element Replacement .

Is the repair complete?

--

Go to Step 29

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26

Test CKT 182 (YEL) for a short to ground. Refer to Testing for Short to Ground in Wiring Systems.

Is there a short to ground in CKT 182?

--

Go to Step 28

Go to Step 27

27

Replace the body control module (SBM). Refer to Body Control Module Replacement in Body Control Systems.

Is the repair complete?

--

Go to Step 29

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28

Repair the faulty wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 29

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29

Perform the Heated Seats System Check.

Refer to Heated Seats System Check .

Was the Heated Seats System Check performed?

--

System OK

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