Electronic speedo on Fiesta MK5 does not work. Somebody tried to jump start and reversed leads. Fuses OK. Help

Question

I have checked all the fuses in the main and auxiliary fuse boxes. The only one which was blown was the ECU which I replaced. Everything works fine apart from the speedo - the LCD display lights with total mileage and odometer which allowed me to reset to zero but the miles do not clock up, nor does the speedo needle move. Help would be greatly appreciated.

Answer 1

hi there sorry to hear of your misfortune, it sounds like the reversed leads have blown out circuit board in dash probably nothing to do with speedo but battery feed to dash if you are a bit handy take out dash and strip down if the fault is in dash you will probably find a burnt piece if printed circuit board and if it is not too bad you can solder a thin wire into it, jock

Answer 2

You should find where the wires plug into your transaxle, right behind the engine, and see if the wires are burned or broken. Trace them back as far as you can. Changes are they got melted when the polarity was reversed on the battery. It may be that you can just cut the wires back a ways and take the old plug to the dealership and get a new one and splice it back on.

Answer 3

Probably just fried something in the electrical system i'd check the fuses first starting with the ones under the hood otherwise take it to a reputable mechanic and have them look it over. It should be fixable but it may be expensive depending on what got fried

Answer 4

i think its broken & your friend is a very silly person
go to ford they will plug and play and give you a complete list
oh and there will be fault code on the ecu now!

Answer 5

Prepare to get your wallet out! You need new electronic parts. Things just aren't repairable nowadays