Circuit/System Testing: Notes
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B2345 00
- Ignition OFF, disconnect the MSM connectors C1 and C4.
- Test for infinite resistance between the left seat heating element supply voltage circuit terminal 14 and ground.
- If less than infinite, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
- Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 14 and ground.
- If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
- Test for infinite resistance between the right seat heating element supply voltage circuit terminal 6 and ground.
- If less than infinite, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
- Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 6 and ground.
- If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
- If all circuits test normal, replace the MSM.
B2345 13
- Disconnect the MSM connectors C2 and C5.
- Verify the resistance through the faulted seat heat sensor is 850-300K ohms from the signal circuit terminal to the low reference circuit terminal in the harness connectors.
- If less than 850 ohms, replace the seat heater element.
- If the circuits test normal replace the MSM.