Our Ford Mondeo's electrics have completely failed. Any ideas?

We have a Ford Mondeo estate. It has always gone pretty well. We went out on Saturday and it drove fine. Stayed at home Sunday and on Monday morning went out to start it up. Nothing. No electrics at all, no 'click click' from the starter that you would expect with just a dead battery. We tried jump-starting it, but all that happened was the horn blew when we attached the leads. We left it connected for a good half an hour but still nothing. We have looked at the fuses and can't see any that look broken. We have checked for loose connections or cables. Any ideas?

Asked on 6 August 2010 by mrmondeo

Answered by Alan Ross
Am I correct in saying that you have slaved the car from another car (with that car's engine running) and ensured correct polarity when slaving? When connected before attempting to start, do the car's headlights and side lights come on? It sounds very odd to have nothing at all. I would suggest that you check the main battery leads first, both positive and negative, especially the earth lead to the chassis.

Do you have a manual for the vehicle? You may have to start checking the electrical wiring diagrams to find out where the main fuses are. I am afraid that it is difficult to assess from a distance. If you are a member of the AA/RAC and have home assistance, they might be able to identify the fault.
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