Technical Battery disconnect

[drofdarbnomis]

Hello everyone,
Can anyone tell me if the ecu will be affected if the battery is disconnected for several months?
Thanks
Simon

 

[renaultvation]

It shouldn't. I carry a spare ECU in the boot of my Cabrio and every so often I plug it in to check it is ok and it works fine. However, I do have a 1.6 which uses a GM ECU and ignition system, so I don't know whether it behaves differently from Magneti Marelli equipped Puntos.

 

[rolandbrindley]

Not all Punto Mk1s are coded, mine isn't and it's August 1994. Look at your key carefully, if it's got a blue moulded plastic finger pad that has no obvious openings or splits in it then your car isn't coded and you can disconnect the battery for as long as you like. If it is coded you will probably get away with it, because the battery will already have been changed several times, and if it survived that it will survive any disconnect. Some cars will not survive any kind of battery disconnect without reviving them by inputting the PATS code afresh using some commercial device or other. Find out what you have first.

 

[renaultvation]

Good point. I forgot that my car is also August 1994 and pre-dates the coded keys.

 

[blu73]

if its a 55/60/75/85, or in other words a fiat fire engined model with the fiat iaw ecu and not a 1.6 or 1.4 turbo, it will be totally fine - you can leave them disconnected for years without issue. The only thing that happens is it loses any stored engine fault codes, which happens immediately once the battery is disconnected. I would expect the others to be fine as well but I've not had one so I can't say with certainty on them.

 

[Steve gt]

I very often leave the battery disconnected on my GT for long periods while it’s garaged up and I’ve never had any issues over the years [emoji1303]

 

[blu73]

actually thinking back, when i had a GT it sat for long periods with no battery (and some other stuff disconnected). As when i had that car my house was broken into and a key for all my cars stolen (had like 7 or 8 at the time) - so i had to make them all not be able to start cause couldnt afford to get the keys and immobilsers changed on all of them at once. Never had an issue with that.

But I have had IAW ECU's sat on shelves in shed/garage for years and then connected them to completely different cars than they came out with absolutely no issue so I'm very confident they are okay haha - The IAW ECUs have a separate codebox that matches the ecu and key so if you change one you have to have all 3 bits or it won't work, so its hard-coded in, it will never forget it

 

[rolandbrindley]

No problem if not a coded car, my October 1994 Punto 55 has gone years with no battery attached. But my Land Rover Discovery would not even tolerate a quick battery change without a slave battery and jump leads to bridge the gap. I had my Discovery ECU modified with a hard-wired mod to enable it to crank the engine even if the PATS code was corrupted and could not be input with the EKA procedure.