After failing to start last week my 1.3mpi now has a flat battery. Is it wise (for the sake of the ECU) to disconnect the battery from the car before applying the charger to the battery? Other than the loss of the radio code is there anything else to worry about if I do disconnect it?

It seems that the head gasket may be on the way out - have not observed any overheating but there are signs of brown sludge accumulating in the coolant expansion tank and I think the coolant level may have dropped slightly in the last few weeks. Assuming I don't try to run the car like this for any length of time is there any risk to the engine if I try to get it started once the battery is charged?

Thanks!

After failing to start last week my 1.3mpi now has a flat battery. Is it wise (for the sake of the ECU) to disconnect the battery from the car before applying the charger to the battery? Other than the loss of the radio code is there anything else to worry about if I do disconnect it?

It seems that the head gasket may be on the way out - have not observed any overheating but there are signs of brown sludge accumulating in the coolant expansion tank and I think the coolant level may have dropped slightly in the last few weeks. Assuming I don't try to run the car like this for any length of time is there any risk to the engine if I try to get it started once the battery is charged?

Thanks!

For any battery charging I would disconnect it from the car. I have always disconnected batteries before charging them even on my dads old Toyota Hi-Ace Campervan. It is just a sort of safety thing.

I've never had any problems with a trickle charger, but I've also never used one on a car with an EMS.

I'd always disconnect and remove the battery before using a "high speed" booster charger though.

if you have a standard blaupunkt stereo then it shouldn't make a difference when unplugging the battery. as they have a security card not a code.

(thats if that is the std one)