code p0380 2000 jetta TDI

tg2122460

Member
Joined
Mar 11, 2007
Location
Guelph, Canada
TDI
2000 1.9
Hi folks, hopefully someone can help, I have a P0380 code Glow Plug / Heater 'A' circuit.

The voltage at all 4 flow plugs jumps only microvolts when the ignition switch / glow plug dash light is lit. Both wires on the harness from the hidden connector to each GP socket harness seems good (ohm meter) and each glow plug measures the same resistance (about 1 ohm).

The circuit seems to be dead so I'm thinking there must be a relay (under tha dash?) that controls this circuit, where is it?

Any other ideas?

Can someone point me to a wiring diagram.

Thanks
Tim.
 

tg2122460

Member
Joined
Mar 11, 2007
Location
Guelph, Canada
TDI
2000 1.9
An update - it appears the GP circuit may in fact be fine. With the coolent sensor disconnected the glow plug circuit voltage goes to 12.55 volts for approx. 20 seconds at each GP socket. It is a 2 wire harness.

So now I'm wondering why the engine light went on in the first place. I had a shop give me the stored code when it was in for other work, now I need to reset it. I'm in Guelph as well.
 

P2B

Top Post Dawg
Joined
Jan 11, 2006
Location
Toronto & Muskoka, Canada
TDI
2002 Jetta, 2003 Jetta, 2003 Jetta Wagon
tg2122460 said:
So now I'm wondering why the engine light went on in the first place.
Often caused by oxidation of the harness contacts at the glow plugs, in which case simply disconnecting and reconnecting the harness to check glow plug resistance may have already fixed it.

I had a shop give me the stored code when it was in for other work, now I need to reset it. I'm in Guelph as well.
I suggest posting a request in the Ontario forum, hopefully you can find a member closer than me (Toronto, DVP & 404) with VAG-COM to reset it for you.

Simon
 
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