Master IV, 2,3DCi fault code CDT038015 SOLVED!

[Orchid70]

Hi
The van is from 2011. (VIN VF1**************[VIN obfuscated, can be read by forum staff] )
Fault code 038015 Pre heating diagnosis connector open ciruite - appeared.
I was a bit fast and changed the plugs - it has run over 200000 km.
After that I started to check the voltage at the plugs - its constant ~5V.
So I changed the relay.
Still same.
Does someone have an idea to where to start looking next?
Thank you!

[Orchid70]

Its too cold outside at the moment. But I have checked this:
There is 12V into both red wires.
There is 3,5V on all the three other small wires with ignition on - untill the throttle body turns silent, then voltage drops to 0.
Does someone know how to test these relays? Perhaps have a wiring diagram for them?
The relay I got is used. So there is a possibility it is faulty. There is no glow plug light on this van, as far as I can see, so if you dont read the fault codes, you dont know something is wrong.
Tomorrow I will try to activate the relay with the computer and measure.
I would be very thankfull if someone had the wiring diagram for this engine/glow plug relay.

[Orchid70]

The problem is solved!

When I realised there are TWO relays for glow plugs, that is, when I found the other relay - I found the problem.
The fault code 038013 is for the smaller relay (with only one connector, with a blue locking mechanism), behind the Plus pole for charging the battery. The part number is: 110678071R
The big realy (two connectors) has part number: 8200558438A

Well, the realy was ok, in the end, but when I removed the connector I happened to notise a small, small kind of damage. It only looked a bit dodgy, thats it. When I scrathed the surface with my nail, it looked like there was no wires inside. It was the grey/greyish, thinnest wire. 0,5 or thinner. Almost at the pin it self.
I removed the yellow locking plate and removed the female pin. And managed to repair it with a small piece of wire and crimps.
Everything back together and the fault code for "diagnose connection to pre heating realy" - gone.
It started to rain so didnt get any pictures.
When I repair wires on any car, I use these crimps (from an other repair):

[mickthemaverick]

Well done and good to see a write up for other member's benefit!!

[Orchid70]

Well - dont you just hate when you find 100 questions of the type you have - and NONE results =)

[Dormouse]

Thanks very much for your perseverance - both in solving your own problem and for sharing it here on FCF. It was a non standard problem with no real clues and no obvious codes to pinpoint the issue. It proves you are a capable problem solver with sound basic knowledge. Pat yourself on the back. Personally, I would have struggled with this one and I would like to think I could have solved it but who knows how long it would have taken. I speak for quite a few others when I say that it is a two way street here on FCF and while I don't always partake in a thread I do read it. The little nuggets that turn up are invaluable and add to all our "Knowledges".
Again thanks for being part of FCF. And to all the others who contribute, a big thank you too.

[Orchid70]

Thank you =)

[Dormouse]

No, thank you! I am just a spectator on the sidelines of this one.