Implausible Ignition Key Off Time Received
Table of contents
U1421 RAM Possible Causes
- Faulty Body Control Module (BCM)
- Body Control Module (BCM) harness is open or shorted
- Body Control Module (BCM) circuit poor electrical connection
- Faulty Powertrain Control Module (PCM)
How do I fix code U1421 RAM?
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’s pins.
Cost of diagnosing the U1421 RAM code
The cost of diagnosing the U1421 RAM code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
U1421 RAM Description
The Body Control Module (BCM) monitors the time the ignition is in the off or accessory position between key cycles and then broadcasts the signal called Ignition Off Time (IOT) via the CANC Bus. The Powertrain Control Module (PCM) saves the value from a previous key cycle into powerdown flash and if certain When Monitored conditions are met compares to the current value. If the Set Conditions are met, then a fault U1421 is set indicating the timer is stuck. If this fault becomes active the PCM will light the MIL light immediately. If the MIL is set and the fault goes stored the PCM turns off the MIL after 3 consecutive drive cycles. If the difference between two Ignition Off Times (IOT) sent from the BCM to the PCM during two separate diagnostic decisions is less than 3 minutes for 5 consecutive decisions this fault will set.