U3921

U3921 Ford engine fault code diagnosis, code meaning,symptoms and how to fix it.

U3921 Diagnosis

This fault indicates that the circuit is drawing more current than it is designed to supply, and possibly there is a wiring fault shorting this circuit to ground. The fault remains active until the ignition is turned ON when the fault is no longer present.The BHM supplies battery power on this circuit when the key is in the RUN or CRANK positions. Troubleshoot for a wiring fault shorting this circuit to ground or for too many optional circuits spliced into it that is causing the BHM to turn it off.

When the engine is in higher engine speed and torque condition, the differential pressure over the DPF is expected to rise according to engine speed and torque. If the differential pressure exceeds a threshold then the differential pressure sensor plausibility DTC is set.

Ford U3921 Fault Code Meaning :

Ford U3921 Symptoms :

Ford U3921 Reasons :

How To Fix Ford U3921 Trouble Code ?

A code is a fault code and it indicates that something has gone wrong with your car's engine.

It can be caused by many different problems, including a faulty battery, a bad fuel pump, or even a cracked exhaust manifold.

You will need to diagnose the problem before you can fix it. The best way to do this is with an OBD scanner tool.

A scan tool will tell you what needs fixing and how much it will cost in order to fix that particular issue.