OBC Retrofit issue

[Laith]

Hey all,

Have retrofitted a full 13 button OBC as per the instructions in the wiki.

Everything pretty much works except I have two confusing issues I cant get to the bottom of.

1) if I plug in the green and green/red plug into the back of the main control box behind the glovebox, the car wont turn off after I start it then take the key out. Weird. To turn it off I have to unplug that cable. The OBC pretty much works fine without it.

2) The OBC code program wont work. If I enter a code to immobilise and get it wrong, its relay just clicks. I can still start the engine with no issue.

Any ideas?

[Laith]

Have since found I have the wrong OBC coding plug for my car; its type 4,6 which is for a 325 I think, whilst mine is a 320i.

I'm sure though that the wrong coding plug would only affect the reliability of the fuel, mpg etc, and not the OBC coding function.

Anyone ever fitted an OBC?

[Brianmoooore]

Wrong coding plug is nothing to do with your problem.
What happens if you don't plug the green - green/red into the relay box? The car shouldn't start at all.
When it refuses to turn off, unplug the red/white wire from the accessories socket and see if that kills it.
I have half a feeling that we've had this problem before, but I can't remember what the solution was.

[Laith]

I keep that green, green/red unplugged now so I can turn on and off the engine normally.

Will try the accessory red/white from the main control box tomorrow. What does that even do?

Cheers for all the help with the other stuff btw, sounds like you're the expert here.

[Laith]

Ok unplugged the red accessory and put the ignition green plug back in and I've still got the same problem. Engine doesn't turn off. For now both are unugged.

[Brianmoooore]

Engine shouldn't run at all with the green-green/red unplugged at the relay box.
Where is the other end of the this wire connected? (Behind glove box.)

[Laith]

It's the green green red from the obc loom that I'm talking about. If I follow that wire it connects to the obc ecu, and the plug it plugs into is on the main control box behind the glove box where there's loads of other connections that I guessing goes to the fuse box?

[Brianmoooore]

It doesn't plug into the main accessories socket. It plugs into a white socket hanging down from the loom above the top of the glovebox with two plain green wires going to it. There should already be a plug connected into this socket with can just have a short loop of green wire connected to it, or may have wiring to an immobiliser.

[Laith]

Ahh I see, will try that. There is an immobilizer though, best to use the obc? Or both somehow?

Does the red plug go into the back of the main accessory socket?

[Brianmoooore]

Red/white wire goes into the accessories socket. More than one immobiliser can be connected.

[Laith]

Ok so would I splice the obc cable onto the previous immobiliser two green wire circuit?

[Brianmoooore]

Yes.

[Laith]

Sweet. Cheers for all the help. If I ever see you at a meet I'm buying you a beer!