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So, if you bridge the relays "output side" wiring at the fuse-box the compressor runs; but it won't run even when you see/feel/hear the relay operate? This is illogical.
P38A P38 Compressor wont start automatically
- Thread starter P4wn33
- Start date
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wait wait wait there is nothing of that "see/feel/hear the relay operate"
EDIT: it's still the same problem that the relay wont start to work
I checked the wire connection between the fuse box and the ECU and I have below 0,5 Ohm, so the connection is good.. :/
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Sorry to ask... has this been done yet?
yep since 2019
tomcat59alan
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Sorry to be so pedantic (or perhaps stupid?)... but is this ground side of the relay missing?
If it was missing then even if the ECU says "RUN" there is no circuit and R20 will never operate and the motor cannot run.
If it was missing then even if the ECU says "RUN" there is no circuit and R20 will never operate and the motor cannot run.
hmm.. I can't imagine that, but I will see it when I disassemble the fuse box. But I can only do it on the weekend because I don't have much time this week.
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Behind the left hand side kick panel the wires come down by the A-post and there are a load of white connectors. These sonetimes get corroded so people cut them and solder them with that heatshrink stuff around the join.
Hopefully someone can post a picture or the connector from RAVE.
tomcat59alan
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From memory there is an earth point by the front of fuse box on the inner wing.worth checking it's clean and tight
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Thought he'd checked that. Strange thing is diag does the same thing but when he forces on with Nanocom it doesn't run. So must be dodgy connection sonewhere.
Datatek
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Depends on your experience, not easy if you are not used to dealing with printed circuit boards.
More tests needed first. If you put a jumper wire across pins 2 & 5 of the relay socket, does the compressor run?
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I did ask this at post 41 Keith.
Datatek
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Yes, I saw it after I posted
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I am not sure we got an answer though.Yes, I saw it after I posted
I thought it would be a good test to prove earth & live continuity out to the compressor and see whether it might be the relay internal contact failed or the relay itself has failed.
I also suggested swapping it for another like-type relay in the fuse-box.
Datatek
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I see the OP now says the relay doesn't actually operate, so the problem is between the relay and the ECU or as others have said a bad earth.I am not sure we got an answer though.
I thought it would be a good test to prove earth & live continuity out to the compressor and see whether it might be the relay internal contact failed or the relay itself has failed.
I also suggested swapping it for another like-type relay in the fuse-box.
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But, if the relay doesn't operate it is either a failed relay (swap it) OR the wiring is bad (fix it) OR when you jumper out the contacts of the relay IF the pump runs it must be the relay has failed. No?
Bridging the relay proves everything else is good if the pump then runs. If it doesn't it is a failed pump or duff wiring but you have proved it is or is not the relay itself.
Datatek
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No signal from the ECU and the relay will not operate, same if the earth path is bad either of which could be wiring or the fuse box.
OP, with the relay removed, put one lead of a voltmeter set to 20 volts in pin #1 of the relay socket and connect the other lead to an earth point, then with diagnostics command the pump to run and see if you get a reading on the meter.
hehe I'm still allive and I will share the solution but I was not home last week and I didn't really have much time last week.. If the weather is okay, I will check all of that tomorrow
but first of all thanks to everyone to help me!
