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Driver's Thermistor Out Of Range Low

  1. Raise seat to highest position to access seat connectors. Disconnect driver's heated seat cushion Black 4-pin connector located at rear of seat. Turn ignition on. Using DVOM, measure voltage between driver's heated seat cushion connector terminal "D" (Brown/White wire, harness side) and ground. If voltage is less than 4.5 volts, go to next step. If voltage is greater than 4.5 volts, go to step  7.
  2. Turn ignition off. Using DVOM, measure resistance between driver's heated seat cushion connector terminal "C" (Black/Red wire) and "D" (Black/Red wire). Ensure seat is at room temperature. If resistance is less than 7000 ohms, go to next step. If resistance is greater than 7000 ohms, sensor is open. Replace driver's heated seat cushion. See appropriate POWER SEATS article. Perform MEMORY/HEATED SEATS VERIFICATION TEST  under VERIFICATION TESTS.
  3. Disconnect Heated Seat Module (HSM) connector C1 located at front of seat. Using DVOM, measure resistance between HSM connector C1 terminal No. 9 (Light Blue/Black wire) and ground. See Figure. If resistance is greater than 1000 ohms, go to next step. If resistance is less than 1000 ohms, repair short to ground in Light Blue/Black wire between HSM and driver's heated seat cushion. Perform MEMORY/HEATED SEATS VERIFICATION TEST  under VERIFICATION TESTS.
  4. Using DVOM, measure resistance between driver's heated seat cushion connector terminal "C" (Black/Red wire) and ground. If resistance is greater than 1000 ohms, go to next step. If resistance is less than 1000 ohms, sensor is defective. Replace driver's heated seat cushion. See appropriate POWER SEATS article. Perform MEMORY/HEATED SEATS VERIFICATION TEST  under VERIFICATION TESTS.
  5. Using DVOM, measure resistance of Light Blue/Black wire between driver's heated seat cushion connector terminal "C" and HSM connector C1 terminal No. 9. If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair open in Light Blue/Black wire between HSM and driver's heated seat cushion. Perform MEMORY/HEATED SEATS VERIFICATION TEST  under VERIFICATION TESTS.
  6. Replace HSM. See MEMORY HEATED SEAT MODULE, HEATED SEAT MODULE, MEMORY SEAT MODULE  under REMOVAL & INSTALLATION.
  7. Disconnect Heated Seat Module (HSM) connector C1 located at front of seat. Using DVOM, measure resistance of Brown/White wire between driver's heated seat cushion connector terminal "D" and HSM connector C1 terminal No. 18. If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair open in Brown/White wire between HSM and driver's heated seat cushion. Perform MEMORY/HEATED SEATS VERIFICATION TEST  under VERIFICATION TESTS.
  8. Using DVOM, measure resistance between HSM connector C1 terminal No. 18 (Brown/White wire) and ground. See Figure. If resistance is greater than 1000 ohms, go to next step. If resistance is less than 1000 ohms, repair short to ground in Brown/White wire between HSM and driver's heated seat cushion. Perform MEMORY/HEATED SEATS VERIFICATION TEST  under VERIFICATION TESTS.
  9. Replace HSM. See MEMORY HEATED SEAT MODULE, HEATED SEAT MODULE, MEMORY SEAT MODULE  under REMOVAL & INSTALLATION.
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