QUOTE 71-bda
wasn’t there a case of an earth terminal block in the passenger footwell needed tightening that fixed a similar issue a while back ?
/QUOTE
Yes that was mine and triggered many warnings and fault codes, primarily that the O2 sensor had failed – Ford were *appalling* at diagnosing the faults and preferred just to fit 3 new O2 sensors over the course of a couple of months, in the hope that that would fix my many electrical faults – including intermittent interior and ambient lights and 6 fault codes triggered in the audio system – which was basically complete incompetence, because who on here thinks that changing an engine O2 sensor can fix 6 audio faults and the ambient light faults that all occur simultaneously?
Since this fault also sounds like it could be a faulty *ELECTRICAL* component, rather than a physical one – the first basic checks must be that the fuses and relays all work properly, that the earth points on *ALL* of the various cars electronic control modules are connected tight and that the electronic modules themselves aren’t fried or short-circuiting.
For me it turned out to be the earth point on the Body Control Unit (BCU) under the passenger footwell was intermittently loose. An intermittent fault in some components can be stored as a permanent fault if they are triggered 3 times. So once the car had triggered the O2 sensor fault 3 times – on an intermittent fault – the OBD system stored the O2 sensor as the permanent fault. Bearing in mind that there were over 30 other faults stored in the ECU, it is a simple thought process and mental step to ignore the O2 sensor in favour of an electrical glitch. Sadly, my Ford dealer weren’t in favour of using their own brain or mental thought processes, so be wary that yours might have their thought processes inhibited too.
Best of luck
Mark H
// ’17 Nitrous Blue // Forged Alloys // Michelin Super Sports // Painted Calipers // Sync 3 // Lux Pack // Winter Pack // Black Gel Spoiler Badges // Blue Gel Wheel Inserts // GTechniq Liquid Crystal // GTechniq Alloy Armour // sold Jun ’18
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