Glow plug connections

[marts66]

Hi all, I'm sure this has been covered before but after searching I can't find an answer without asking. I have a 'J271 P0684 Implausible signal glow plug module' fault code on a 2004 cupra tdi.

I have changed the glow plugs as this is an easy job and found the module under the scuttle panel, there was a dirty connection (the large one) which I have cleaned and also cleaned the connections in the plug.

From reading, I have seen there is another connection under the battery? Which I should be looking at before condeming the bridge loom, does anyone have a picture or directions to this? Also, is there a history of the glow plug module itself going faulty?

 

[sockpuppet]

I have seen a thread where a few people had corrosion on the glow plug loom underneath the battery, so thats worth checking out.

 

[marts66]

Flippin' eck. Never rains but pours. Cleaned the connections to the glow plug module and next morning, flat battery!!! After mucking around eventually say smoke coming out of glow plug module, I must have created a short in the relay which was draining the battery. However, in trying by a process of elimination if there was another fault, managed to break the main power lead to starter motor which needed replacing. So, as we are is, no glow plug module attached, car starting, ems light on, still unsure what the funk I did to to cause a short, good god!!!!!!!