OBC and Coding help please.
I've followed the various internet instructions to retrofit a full OBC to my 1993 525i Touring and although its working, I need some help.
I was aware that its had a drivers side prang but the repair is very good and it tracks straight and true.
It came with the digital clock with the outside temp only.
I purchased a full OBC from eBay that supposedly came out of a late model 5-series but they didn't say what.
I've fitted it and it's working straight up - sort of.
I suspect the fuel and range figures and such to be inaccurate.
Everything else seems to be okay.
From research about the retrofit, I gather that on my vehicle, the coding board is part of the instrument cluster.
I've come to the conclusion that my steering column and possibly the instrument cluster have been replaced by used parts as part of the accident repair.
I think so because for a start, I have the push button on the cruise control to operate the OBC in the dashboard (not that's its working) and if the car originally came from the factory with just the digital clock version, then there wouldn't be a need for it - right?
Then also I've unlocked the OBC and gone through the firmware version stuff mentioned in the articles.
Mine comes up 5-6 1991.
According to the internet articles, its for a 535i (I guess a 1991 model perhaps?)
This is where I come unstuck.
Is this firmware confirmation for the OBC itself, or for the coding board?
If its for the OBC, then I shouldn't have a problem I think because the coding board is supposed to supply the correct engine size, fuel tank size, tyre diameter etc etc to the OBC for my car.
However, if that's the coding board information, then the OBC is getting the wrong info for my car and its understandable that the figures will be incorrect.
(e.g.: it tells me I have a range remaining of 528klms, but the tank is at 2/3rds and a full tank hasn't given me more than 420 klms yet).
If I need to change the coding board, is it possible to do so or is it so integrated with the instrument cluster that its not possible?
I realise that by using the correction factor, it may be possible to correct the fuel consumption figures, but it still won't give me correct range or fuel remaining or such useful info. Also I read that if the car isn't driven for a couple of days, the correction factor will default back. (as I leave the car at the airport for up to a week at a time, this won't suit me).
Next problem then is the switch not working.
I haven't striped out under the steering column to see if its plugged in (and obviously I will do so) but there's no reason to think it wouldn't be as a mechanic replacing a steering column from a wrecker would be inclined to plug in everything that had a matching plug.
Are there any other tricks to getting the dash display to work before I take the lower dash apart?
Hoping someone can assist.
ss2115.
BMW 525i Touring - 1993 (current drive car).
DS23 Citroen Safari - 1974 (restoration and modifications).
Golf MkIII - 1997 (fun car and daughters learn-to-drive car)