Diff lock unit

[omlaysause]

Folks,
As I've currently got the centre console stripped, my oil temp doesn't work on the diff lock unit. The oil temp sender and the wiring are both okay. So I need someone to check the unit for me, any ideas?? . . . or is it something that'll need renewed?

[Jim Haseltine]

Typically crappy piece of 80's electronics - built way down below budget. Luckily, the same circuit board was used in all sorts of quattros - 80 saloons are probably the most common.

[Julian]

So I need someone to check the unit for me, any ideas?? . . . or is it something that'll need renewed?

I had a faulty oil temp display on my MB when I first got it - its display is a column of LED's, so I'm not sure if this is the same as a WR?

Anyhow, I opened the unit up and discovered an obviously burned resistor on the circuit board behind the LED's. I could not determine its value due to the colour bands being burned and a multimeter indicated an open circuit.

Carefully I replaced it with a small pre-set potentiometer (the value of which was a semi-informed guess!) and after a bit of adjustment found that the gauge now worked perfectly. Three years later and it's still fine.

It would be well worth you having a look here too IMO, if you're lucky it could be the same as mine