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Driver Thermistor Out Of Range Low

When Monitored: With the ignition on, during the heated seat operation.

Set Condition: This condition is immediately set when the Heated Seat Module senses a lesser value than the value stored in EEPROM.

Possible Causes are:

NOTE: Raise the seat to the highest position to gain access to the connectors. The HSM is located at the front of the seat and the Seat Heater connectors are at the rear of the seat.
  1. Turn ignition off. Disconnect the Driver Heated Seat Cushion 4-way connector. Turn ignition on. Measure the voltage between the seat sensor 5-volt supply circuit and ground. Is the voltage less than 4.5 volts? If yes, go to next step. If no, go to step  3 .
  2. Turn ignition off. Disconnect the Heated Seat Module C1 connector. Disconnect the Driver Heated Seat Cushion 4-way connector. Measure the resistance of the seat sensor 5-volt supply circuit between the Heated Seat Module connector and the Driver Heated Seat Cushion (harness side) connector. Is the resistance less than 5 ohms? If yes, replace the Heated Seat Module (5-volt supply open). Perform MEMORY SYSTEM VERIFICATION TEST  under VERIFICATION TESTS. If no, repair the open seat sensor 5-volt supply circuit. Perform MEMORY SYSTEM VERIFICATION TEST  under VERIFICATION TESTS.
  3. Turn ignition off. Disconnect the Driver Heated Seat Cushion 4-way connector. Measure the resistance between the seat sensor 5-volt supply circuit and the driver seat temperature sensor input circuit at the driver heated seat cushion (cushion side) connector. Is the resistance more than 70,000 ohms at room temperature? If yes, replace the driver heated seat cushion. Perform MEMORY SYSTEM VERIFICATION TEST  under VERIFICATION TESTS. If no, go to next step.
  4. Turn ignition off. Disconnect the Heated Seat Module C1 harness connector. Disconnect the Driver Heated Seat Cushion 4-way connector. Measure the resistance of the driver seat temperature sensor input circuit (harness side) and ground. Is the resistance less than 1000 ohms? If yes, repair the driver seat temperature sensor input circuit for a short to ground. Perform MEMORY SYSTEM VERIFICATION TEST  under VERIFICATION TESTS. If no, go to next step.
  5. Turn ignition off. Disconnect the Driver Heated Seat Cushion 4-way connector. Measure the resistance between the Driver Seat Temp Sensor Input circuit cushion side) and ground. Is the resistance less than 1000 ohms? If yes, replace the driver heated seat cushion. Perform MEMORY SYSTEM VERIFICATION TEST  under VERIFICATION TESTS. If no, go to next step.
  6. Turn ignition off. Disconnect the Heated Seat Module C1 connector. Disconnect the Driver Heated Seat Cushion 4-way connector. Measure the resistance of the driver seat temperature sensor input circuit from the Heated Seat Module connector to the Driver Heated Seat Cushion connector. Is the resistance less than 5 ohms? If yes, replace the heated seat module. Perform MEMORY SYSTEM VERIFICATION TEST  under VERIFICATION TESTS. If no, repair the open driver seat temperature sensor input circuit. Perform MEMORY SYSTEM VERIFICATION TEST  under VERIFICATION TESTS.
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