WVO 9Y
W0L0TGF7542188747
'05 Vauxhall Zafira
2.0 DTI
Y20DTH

Hi guys,

A local tech friend of mine has recently fitted a new clutch to his Zafira and ever since has had an 18amp power drain, (drops to 12amps after 30 secs or so). Its the heater plugs that are stuck on!

Now when i pulled the Wiring diagram from Autodata for his engine (PSG16) he has power at all the relevant places of the glow plug relay as you can imagine with the system being active; +30 @ pin3, +15 @ pin8, -31 @ pin7! All load test good! if i unplug the relay the glow plugs switch off as they do with the fuse removed so its either the relay or the control of it!

Relay pin9 which comes from the ECU has NBV regardless of the component activation status. normal?
Relay pin6, again from the ECU shows 3.3v glow plugs off, 0v glow plugs on. Retested at ECU pin4 with the same result. Checked with TIS and this says it should be 12v & 0v depending on component activation. Live data reads ok with TIS specifications. I assume the way this system works is the relay is active and receives a voltage from the ECU to interrupt the connection and turn the plugs off??

Now I'm not a big fan of TIS2000 as it has led me to a couple of incorrect and expensive conclusions in the past so i wonder if anybody can confirm if what it is telling me is true or not please?

I popped the pin out of the multi-plug behind the battery and put a 12V supply to pin6 of the relay hoping this would allow me to control the relay but it made no difference what so ever, they just stayed switched on!

Im now a little stuck as to how to finish my investigation and reach a conclusion as obviously i don't want to just start with the cheapest part and hope for the best!

All input is greatly appreciated, I'm fairly confident that it is not a direct result of the clutch replacement as the guy in question is a very careful technician and one of few people id allow to work on my car if necessary and he says he double checked for such a thing; plus all the wires load test ok!

Thanks
Craig