Check 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 pins.
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What is the Cost to Diagnose the Code?
Labor: 1.0
The cost to diagnose the P1684 code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.
What are Code Possible Symptoms?
Engine Light ON (or Service Engine Soon Warning Light)
What Does the P1684 Code Mean?
The Diagnostic Trouble Code (DTC) P1684 will set when the Transmission Control Module (TCM) is disconnected from battery voltage or ground. The DTC data will be lost. The vehicle will go into immediate limp-in mode if power is lost while operating the vehicle. Normal operation is resumed if the power is restored during the same key start.