Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
The cost to diagnose the P1002 code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
The Transmission Control Module (TCM) uses ignition off time to enable other diagnostic tests. The TCM must verify the proper operation of the ignition off timer to ensure the diagnostic tests are performed within the proper enable conditions. The ignition off timer value is stored in the Cabin Compartment Node (CCN). The CCN will send the ignition off time message to the Totally Integrated Power Module (TIPM). The TIPM broadcasts the ignition off time over the CAN bus. The TCM receives the message and then compares the ignition off timer value to the Engine Coolant Ignition off temperature and the Engine Coolant Start-up Temperature message. The Diagnostic Trouble Code (DTC) will set if the ignition off time is less than a calibrated value based on Engine Coolant Ignition off Temperature and the Engine Coolant Start-up Temperature.
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