For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Heated Seats Schematics
1 | Did you review the Heated Seats Description and Operation and perform the necessary inspections? | -- | Go to Step 2 | Go to Heated Seats Circuit Description
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. Turn ON the ignition, with the engine OFF.
2. Disconnect the inoperative Heated Seat Switch.
3. Connect a test lamp between the ignition positive voltage circuit at the inoperative Heated Seat Switch connector and a good ground.

Did the test lamp illuminate?

--

Go to Step 4

Go to Step 15

4 | Connect a test lamp between the ground circuit at the Heated Seat Switch connector and battery positive voltage. Did the test lamp illuminate? | -- | Go to Step 5 | Go to Step 16
5 |

1. Reconnect the Heated Seat Switch.
2. Disconnect the inoperative Seat Heater Module connector.
3. Connect a test lamp between the Heated Seat Switch signal circuit at the Seat Heater Module connector and a good ground.
4. Operate the Heated Seat Switch.

Did the test lamp illuminate?

--

Go to Step 6

Go to Step 8

6 | Connect a test lamp between the battery positive voltage circuit at the Seat Heater Module connector and a good ground. Did the test lamp illuminate? | -- | Go to Step 7 | Go to Step 17
7 | Connect a test lamp between the ground circuit at the Seat Heater Module connector and battery positive voltage. Did the test lamp illuminate? | -- | Go to Step 9 | Go to Step 18
8 | Test the Heated Seat Switch signal circuit for a open or short to ground. Did you find and correct the condition? | -- | Go to Step 22 | Go to Step 13
9 | Test the resistance through the heated seat thermistor from the heated seat control module connector terminals. Is the resistance within the specified values? | 7K-12K ohms | Go to Step 10 | Go to Step 11
10 | Test the resistance through the heated seat heater elements from the heated seat control module connector terminals. Is the resistance within the specified values? | 2-3 ohms | Go to Step 14 | Go to Step 12
11 | Test the heated seat thermistor reference voltage and signal return circuits for an open, short to ground or short to battery positive voltage. Did you find and correct the condition? | -- | Go to Step 22 | Go to Step 19
12 | Test the heated seat grid voltage supply and return circuits for an open, short to ground or short to battery positive voltage. Did you find and correct the condition? | -- | Go to Step 22 | Go to Step 19
13 | Inspect for poor connections at the harness connector of the inoperative Heated Seat Switch. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 22 | Go to Step 20
14 | Inspect for poor connections at the harness connector of the inoperative Seat Heater Module connector. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 22 | Go to Step 21
15 | Repair the open or short to ground in the ignition positive voltage circuit at the inoperative Heated Seat Switch. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 22 | --
16 | Repair the open in the ground circuit at the inoperative Heated Seat Switch. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 22 | --
17 | Repair the open or short to ground in the battery positive voltage circuit for the inoperative Seat Heater Module. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 22 | --
18 | Repair the open in the ground circuit at the inoperative Seat Heater Module connector. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 22 | --
19 | Replace the inoperative Heated Seat Element Assembly. Refer to Driver Seat and Passenger Seat Back Cushion Heater Replacement and Driver Seat and Passenger Seat Cushion Heater Replacement . Did you complete the replacement? | -- | Go to Step 22 | --
20 | Replace the inoperative Heated Seat Switch. Did you complete the replacement? | -- | Go to Step 22 | --
21 | Replace the inoperative Seat Heater Module. Did you complete the replacement? | -- | Go to Step 22 | --
22 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2