obc retrofit problem

[eamo]

i am retrofitting the 13 button obc into my 320 which i bought the complete kit from here.

with the yellow connector in the back of the speedo, the 2 green connectors in the obc control box and the green connector in the obc itself, i should see uhr on the screen when i turm on the ignition - right?

well no - i get nothing ! any ideas??

have i to install a sperate relay or something in the fuse box??

cheers

[smithy318i]

it should work as soon as you plug the display unit into the instrument cluster.

you might need to check with a multimeter to see if it is getting power.

[ed325i]

It could be that its working but the back light is not working so you cant see the display ??

ED

[Cabrio]

Is all the circuit complete...indicator arm...wire plugged into power supply under pass dash...how many spare wires do you have...

As mentioned the backlight could be out but likely you have not plugged all wires into correct location

[dodgem]

There's only 2 connectors you need to get in, and those are the yellow one into the back of the instrument cluster, and the green one into the back of the obc. With them in place it should work, and if it doesn't then my bet is on the backlight having gone (shine a torch at the screen or wait for the sun to shine on it whilst the ignition is on). If you can see some lettering that way then it's the backlight, if not then the unit is kapput or the loom has a broken wire in it between cluster and obc.

Simon

[ed325i]

A new bulb is only £21.50 from BMW

ED

[appletree]

I got told you could by the bulb for 70p from maplins and solder it in your self.

[eamo]

before i bought the kit i ordered as a precaution the bulb for the back of the obc and the bulbs with the white tray that slides into the side of the obc.

I have now just replaced those 2 items and still no joy.

im confused!!

what fuses/relays control the obc?? maybe its one of them??

[eamo]

just checked fuses 10,12,21,23,27

all are fine.

still confuddled!!

[kam-325i]

What about the single wire that goes into the dist block behind the glove box, and the earth near the block ?

[eamo]

even though you dont need to connect them i did anyway and still nothing

[Brianmoooore]

The only wiring an OBC needs for most functions to work is the connection to the OBC itself (obviously), and the yellow plug to be plugged into the cluster.

[AndrewL]

If you are sure the OBC is a working one (are you?) the only thing you need is the harness to the cluster and the brown wire earth connection to the earthing post behind the glovebox (or anywhere really).

You should be able to test the OBC backlights with a coupla wires and a battery.

BTW, does your post imply you have a spare tray for the OBC backlight? I am looking for one and would offer to rewire and supply you with guaranteed working backlights if you have a spare tray you can let me have/sell me.

Andy Lee

[AndrewL]

PS somebody did have a problem with one of the pins on the cluster plug getting displaced and not making proper contact (although unless you are very unlucky that only oughta kill only one display function).

Try pulling the plug and checking all the pins are in place and evenly lined up. Maybe spray a little contact fluid.

Andy

[Cabrio]

If you have fitted the plug to the back of the clocks and the module is installed above ecu and plug is in back of obc...then rest of loom is attached as indicted all wires under passenger dash inc earth, fuses all checked nothing left but test obc to see if plug is getting power..then you know if the unit has a potential fault..without seeing what you have done or not done with wiring hard to offer definitive advice