P0625 Code and Battery Light On: Ford Fusion

Learn about the P0625 code and battery light on problem in a Ford Fusion

A P0625 code and battery light on indicates an issue with the generator field control circuit on a Ford Fusion. This code, combined with a battery light on the dashboard, typically points to a problem with the charging system. Here’s a step-by-step guide to diagnose and potentially fix this issue:

1. Check the Battery an voltage while running with loads on

Start by checking the voltage at the battery terminals with electrical loads turned on and the engine running—blower, heated seats, defogger, etc. A voltage reading of 13.5 volts or more indicates the alternator is charging. This vehicle is equipped with power management, so the alternator will not charge if it does not require charging. Putting a load on the system will activate the charging mode.

If the alternator isn’t charging

With the engine off, disconnect the 3-wire connector going to the internal voltage regulator in the alternator. Then start the engine and rev it to 2500RPM for a short period while you check the battery’s voltage. Look for at least 13.5 volts.

If the alternator does not charge with the voltage regulator disconnected and the engine rpm at 2500, there may be an open in either the cable from the alternator to the battery or the ground. Use jumper wires to connect a jumper from the battery terminal on the back of the alternator and clamp the other end directly to the battery’s positive terminal. Then, connect a second jumper wire to the alternator case, with the other end connected to the battery negative terminal. Check the battery voltage to see if the alternator is charging. If not, replace the alternator.

If the alternator does charge with the voltage regulator disconnected

Check the brown/red wire in the voltage regulator connector. You should see battery voltage. If not, check fuse #55 10A located in the battery junction box.

©, 2018 Rick Muscoplat