Reverse polarity battery boost - Help
Discussion
Dont ask me how , but i managed to muddle the cables when boosting a flat battery and put the juice through the wrong way.
Whilst the flat battery still shows a voltage the ignition is completly dead so i guess i have fried the electrics. Checked a couple of obvious fuses which seem ok, but i have an "Engine immobilisation" icon lit on the dash. Before i suffer the humiliation of telling some sniggering fool in the dealership what i did does anybody have any tips of what i might try first. It a 2005 Ford Fiesta by the way.
Any help gratefully received
Charlie
Whilst the flat battery still shows a voltage the ignition is completly dead so i guess i have fried the electrics. Checked a couple of obvious fuses which seem ok, but i have an "Engine immobilisation" icon lit on the dash. Before i suffer the humiliation of telling some sniggering fool in the dealership what i did does anybody have any tips of what i might try first. It a 2005 Ford Fiesta by the way.
Any help gratefully received
Charlie
There's a haynes for your car, if you want to try fixing it yourself I'd recommend bagging a copy of it and checking out the wiring diagram. Chances are that the electrics are protected enough to not kill themselves if the battery is connected backwards, but you'll need to trace the fault through.
Just about all of the electronic units in your car will have "load dump" protection. if you are lucky, a fuse (or 3) will have blown before you vapourised the internals of your electronics.....
(there will also be a large "main" fuseable link on (or very close to the battery terminal). Check for continuity to the main fuse box.) I guess you either had a high current battery booster or another car/battery with jump leads connected the wrong way??
(there will also be a large "main" fuseable link on (or very close to the battery terminal). Check for continuity to the main fuse box.) I guess you either had a high current battery booster or another car/battery with jump leads connected the wrong way??
The problem of jump starting cars is becoming really vexatious.
Clearly you made a mistake. We all make mistakes.
There may be surge protectors in the electrics of the car though I think this is unlikely.
The probable outcome is that several of the electronic components have been damaged including the CPU and as others have said this could be very expensive. A freelance sparks for cars may be quicker and cheaper than a Main Dealer. Actually anything may be cheaper than a Main Dealer.
What few car owners realise is that you can blow these components WITH CORRECT CONNECTIONS jump starting, The problem is the surge that can occur if the jumping car is running at the time of connection. A sudden increase in voltage can fry the CPU even though the connections are correct polarity.
Seen this happen too many times.
If you have blown the CPU and need a new ECU for the car ECUDOCTOR is really helpful and really cheap. A LOT cheaper than a new CPU.
I blew my CPU on a Mitsubishi Twin Turbo and Mitsubishi wanted £2000 for a new one. ECUDOCTOR rebuilt my old one for under £300. That's a hell of a saving.
Hope you can sort this. Good Luck
Clearly you made a mistake. We all make mistakes.
There may be surge protectors in the electrics of the car though I think this is unlikely.
The probable outcome is that several of the electronic components have been damaged including the CPU and as others have said this could be very expensive. A freelance sparks for cars may be quicker and cheaper than a Main Dealer. Actually anything may be cheaper than a Main Dealer.
What few car owners realise is that you can blow these components WITH CORRECT CONNECTIONS jump starting, The problem is the surge that can occur if the jumping car is running at the time of connection. A sudden increase in voltage can fry the CPU even though the connections are correct polarity.
Seen this happen too many times.
If you have blown the CPU and need a new ECU for the car ECUDOCTOR is really helpful and really cheap. A LOT cheaper than a new CPU.
I blew my CPU on a Mitsubishi Twin Turbo and Mitsubishi wanted £2000 for a new one. ECUDOCTOR rebuilt my old one for under £300. That's a hell of a saving.
Hope you can sort this. Good Luck
Steffan said:
There may be surge protectors in the electrics of the car though I think this is unlikely.
I'd be suprised if the electronics in your car are not designed to normal standards, ie. ISO7637 (Parts 1 & 2, load dump and reverse polarity connection).It is VERY common for people to connect batteries backwards, so most manufacturers will design/test their systems to withstand such an event without "major" damage etc.
Get your fuses checked first, then start investiating with a multimeter to find out where any breaks maybe in the power feed loom etc
Just got started this morning as working away this week. I have been through the circuit diagram for the starting and charging system in the Haynes manual and all the fuses check out ok. Was thinking that it might be worth just changing the relay for the starter motor.This is earthed via the engine management unit, so if the starter motor is not turning its either the relay is not making because it wont energise due the EMU being fried, or the relay itself is kaput.
Does this sound logical?
Does this sound logical?
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