Ford F ECU Error

ECU problems on these can be tricky. The reduced power and error codes point that way. I had a similar issue on my older Mondeo, and it was a faulty sensor messing with the ECU's readings. Before replacing the ECU, have you tried a system reset? Sometimes that clears things up, at least temporarily. What's the exact error code?

I haven't tried a full system reset yet – how do I do that? The error code mentions a 'defective engine control unit,' but could a dodgy sensor really trigger that? I want to rule that out.

A faulty sensor can cause the ECU to throw a fit and report itself as defective. To reset the system, disconnect the battery for about 30 minutes. That will reset the ECU of all learned values. But if it's consistently showing that ECU error, get it checked out at a workshop – they’ve got the proper diagnostic tools to pinpoint the cause. Could also be a bad ground somewhere.

I tried the system reset, but no luck. A workshop visit was inevitable. Turns out the main relay was defective, causing the ECU to act up. Replaced it for 120€ and everything's running smoothly again. Thanks for pointing me in the right direction!