Pieman

Daft question but – should I disconnect the battery before swapping ECUs?

beryllium

it's better ,but not imperative

Markus

Well, most peeps recommend doing it, just to be safe, but I've done it a few times without disconnecting.

john banks

Turn the ignition off. That is it. I've not blown any or any cars up doing this method so far. Make sure the three connectors click home. The first time you start it it may stall at worst or grumble, sometimes fine. Next time it will start perfectly.

Pavlo

Well, I think it's fair to say the ECUs are quite tough....


Then even don't mind having a new eprom plugged in whilst running, but I can't recommend it.

And then there's the time David W stood on his without it's case on, at speeds in excess of very fast and it broke components off and all sorts.

Never disconnected the battery on mine, although I did when doing the fuel pump.

Paul