Thread: Tdi 300 ZF Auto Temp Light

Have a look under the LHS front, where the two pipes that go to the gearboxes oil cooler, pass the chassis.
I bet that the spade terminal connections are loose and oily, one has probably come off and is grounding intermittently.
Squeeze the connectors slightly to firm them up and wash all the bits and pieces with some pressure pack degreaser then use throttle body spray, after it's clean look for any missing insulation.
Add if both wires are in good condition and the terminal connectors are still in place, then the switch is most likely crook. If you need to change over to another switch, have everything ready first and you will lose only a little oil if you do it smartly.
Hope that gets you fixed.
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