Ford Focus Mk2 56 Petrol Mpg And Average Speed Resets

[jimjamyaha]

Hi,

Been having a weird problem that probably wiring-related... every so often the MPG and avaerage speed readouts reset on my car. This happens when car is started up - the dials shudder before coming online. Then the ECU acts as if it's in training mode for a week or so.

It's like the behaviour when the ECU has been reset by disconnecting the battery - execept all other things that are normally reset are fine (radio/trip distance).

Been happening since early this year - but thought it was down to some faulty sheared wiring from the ignition system to the coil pack connector - but this is now all sorted.

Have tested battery and alternator, volatages etc are fine.

Any ideas/thoughts, or similar experiences?

James.

[artscot79]

make sure the battery connections are tight and have a free battery test done sounds like a battery fault either faulty cell or wrong type of battery should be calcium or silver calcium not lead acid if they are okay then ide suspect the wiring hasnt been fixed or theres another sheared wire somewhere

[IINexusII]

That is exactly the issue i had before my alternator went... id get the wiring checked though since you say the alt and battery are ok

[jimjamyaha]

Hi - an update.

This was the battery. Replaced it with an appropriate Bosch one and all solved!

James.