Guys need help badly. Got in the 300tdi 90 yesterday and for the first time put on the rear windscreen heater. Strangely the truck chugged but did'nt ignite. After 10 minutes of swearing and checking everything sensible I switched off the rear windscreen heater and guess what the truck starts instantly.

Anyway I began investigating the rear window switch wiring and then the whole lot came out of the dash board with two very old pieces of elec tape at the ends of the two leads. Guess what? Its impossible to see what the leads were attached to and my truck now just chugs and does'nt ignite.

It appears that one of the connections on the back of the ignition is missing and using Haynes I can see one dead end of a wire which looks to be white and orange and which would go to the starter relay.

Has anyone seen something like this before? Help

No and yes. It sounds as though they have used the rear window switch as a "fuel cut off switch" Normally when you switch ignition on then power goes to the fuel pump solenoid (switch's fuel on) It sounds like they have made the rear windscreen heater switch into a "manual fuel on/off switch". Basic method of stopping the engine from running.

Run a temporary wire from the battery to the stop solenoid and see if she will fire. If so then what Mercanlandy says is right on the money.