Hi Simon,i have checked on Wis for you, but i can't find that fault code, however i can tell you that i have had several vans in with faulty glowplug timer units because the glowplugs short to earth in the head, then if you pull the plug off the timer unit and check for continuity which you will have, you then fit the new timer unit switch it on and fry the new unit.

So i always check to see what current they are pulling, if you have a power probe you can give each plug a live feed if one trips out that the culprit if you don't have a power probe just use a piece of wire witha 15 amp fuse inline the fuse will blow if you have one going to earth.

If the timer unit is faulty you can remove it cut around the silicone joint and take the lid off then you will see that a "weak link" has blown i just solder a bit of 25 amp fuse wire across it fit it back together and test. make sure you change the offending plugs first running the engine upto temp first helps get the glowplugs out without breaking them off ( been there done that)

Hth

Kev Gundry

Ps you can only do this on the 4 cylinder model
The six cylinder has 4.4volt glowplugs so you can pop them if testing with a power probe.