C3939

C3939 Ford engine fault code diagnosis, code meaning,symptoms and how to fix it.

C3939 Diagnosis

The output circuits that are powered by VBAT2 will all be inoperative. Other fault codes may be present, but troubleshoot for this first. The ICU reads the wiper switch position and sends the status of the switch to the BHM. This fault becomes active when the ICU reads that both LO speed and HI speed are active at the same time.

Troubleshoot for a wiring short to ground fault on any of the CHM output or BHM output circuits discussed above. The fault remains active until the ignition is turned ON when the fault is no longer present. Some BHM configurations force this circuit off until the ignition switch is cycled.

Ford C3939 Fault Code Meaning :

Ford C3939 Symptoms :

Ford C3939 Reasons :

How To Fix Ford C3939 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.