05 2.0 tdci Jump leads wrong way round - kithmo
Having to jump start the step daughter's Rover 25 today I Placed one end of the red lead on her positive terminal and the other end on my negative (it was going dark and the insulation on the leads runs down the back of the battery). I then put one end of the black lead on her negative and was just about to put the other end on my positive terminal when I realised my mistake, phew!.
This made me ponder, what exactly would I have damaged on either car if I had connected them the wrong way round ?
05 2.0 tdci Jump leads wrong way round - injection doc
full marks for spotting it before its too late, seen this done on an Omega MV6 with a flat battery & it blew the ECU for the ABS, sat nav, dash headlamp switch engine alternator ecu etc etc. It actually rendered the car scrap as so much damage had been caused. Sometimes you can be lucky & get away scott free & others its just plain nasty. Hence the use of ni-cad battery packs now to reduce the chance of damage to the donor vehicle
05 2.0 tdci Jump leads wrong way round - Peter.N.
I agree You were very fortunate to spot it. A few years ago a friend of mine connected the battery up the wrong way round on his Sherpa van, all it did was burnt the alternator out but on a modern car it could very easily write it off.
 

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