Glow Plugs - No Power

[Guest wolfman62]

I have been reading the forum for a few months but this is my first post. I have a problem with my glow plug system in that I am getting no power to the plugs. All four plugs have been replaced (two were found to be dead) and I seem to have traced the problem to the fuse box and the relay 'pre glow relay'. I have power to the relay for the glow plugs and if I bridge the two contacts the plugs power up. The problem is the two swithching contacts ( I have tested the relay and it works). One conact goes to the ignition and the other straight to the ECU. The ignition side gives me 12v supply when I turn the ignition on and the ECU side which I presume should be earth from the ECU gives me a feed of around 6v ?????????????

I have had the car plugged in and it did not read any faults???

The Engine temp sensor was changed with no joy, so as a Temporary fix I have fitted a switch and warning light so I can power the plugs manually (Just connecting the switch through the earth on the original relay).

Any ideas????? Has only started causing a problem over the last 4 or 5 weeks.

It is a 1999 TDi 90bhp (With 280,000 miles, yes 280,000 rebuilt top end about 30,000 miles ago)

[Guest Robert P]

I appear to have a similar problem (2002tdi 90bhp - 140K)

 

Glow plugs have been changed - intermittent fault of not starting and now found to have no power to the glow plugs

 

Is the pre glow relay the one beside the battery fuses and can you tell me how you fitted your swith to operate manually - thank you

[Guest wolfman62]

got rid of earth from relay, then put earth through flasher type swithch so it dont stay on if you take your finger off it, then just earth from earth point. As it is through the relay it will not work when the ignition is off etc.