Crumpler

I still get surprised every now and again...
I wasn't aware I had a bulb Control Unit until tonight when I pulled the passenger tray on the 86.5.
VDO 928 641 603 05
Can someone explain what it does...I mean besides"controlling bulbs".


It looks like a smaller version of a ECU brain.
Does it need contacts cleaned or any R/R?

JHowell37

It lets you know when various bulbs are out.

Landseer

The power to the back bulbs is rooted through the module. The comparison of resistance is made. Stop lights, left v right. Taillights +markers, left v right. If a difference, a warning is triggered. Blinkers and backup lights and license plate lights are not routed through module. I've had a module fail and interupt the power to the stoplights.

What is yours doing?

No maintenence unless you see an issue.

Crumpler

Appreciate the explanation, that helps me wrap my head around what it does.

It's, apparently, working fine...I have never heard it mentioned before in any threads on trouble shooting bulb warnings -- but that makes sense. I knew the system didn't like different bulb resistance, but never understood why... thanks Mr. Toft.

hwyengr

This is a key statement. You will not have tail lights if it's disconnected. A kindly fellow motorist informed me of this during evening rush hour traffic one night while the interior was in a state of disassembly.

Landseer

I've had to jumper the module to apply power directly.
It is by-passable.

davek9

That's what I do to run LED's, just jump the in's to the outs at the connector and by-pass it
edit: also called "Lamp controller"