ECU remap - revert to standard tune if battery disconnected?

[Blim_bug]

Hola all,

Can anyone advise whether the ECU will reset itself to the default tune (OEM from factory), if the battery has been disconnected for a prolonged period of time (6 months +)?

[The Wookie]

Shouldn't think so if it's an EEPROM (which I think most are). It's non volatile memory

[ArtVandelay]

The Wookie said:

Shouldn't think so if it's an EEPROM (which I think most are). It's non volatile memory

I would think so. Unless you've attacked it with an electro-magnet or UV lamp (depending on the type IIRC) it should be okay.

[off_again]

I had an E39 that was 'chipped' as well as an Omega V6 - BMW battery died and no issues and the Omega had a cambelt change that the battery was removed during, and again no issues.

[Blim_bug]

crap, it's never simple is it?!

I fitted a cold air induction kit prior to getting my car remapped, it was subsequently off the road for a long period (battery disconnected, hence my question).

It's thrown a couple of engine warnings (running rich) which I was hoping related to too much air / fuel mixture.

Looks like I'll be fitting the standard airbox and taking back to VW then...

[AndrewW-G]

No, the part that is changed wont revert back to oem, however any variable parts of the ECU will reset to default values . . . . . a Porsche 911 /964 for example, uses various sensors to "optimise" the setup if the battery is disconnected for any period of time, with variances in the effectiveness of that adaptation depending on whether the car was driven or not whilst the ECU re learns.

If its throwing errors, get the car nice and warm, disconnect the battery for half an hour or so . . . . . . .reconnect, start the car and as quickly as possible take it for a drive, using full throttle where your able to.

Have you got any of the diagnostic codes out of it for the errors? . . . . . . .and did you remember to wipe all the DTC’s

Edited by AndrewW-G on Monday 24th May 16:45

[steveclark]

Dose that mean that if I reset my ECU because my central locking is playing silly beggars, that my remap will be wiped? It's a 2000 Passat TDi by the way.

Cheers.