dead heater fan?

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SPADGE
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Post Fri Oct 06, 2006 7:30 pm

Just discovered the fan for the heater on my 335 conversion touring (93 lux) isn't working :? Would rather sort it now before i put the engine etc in.
For a start what fuse number does it run off? All the fuses look ok but if i know the correct one i can trace it from there.
Is there a relay for it somewhere??
Its not the switch as i've tried an known good one!
I hope i don't have to replace the motor as its a ballache and worse than changing a lump imo :?
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Brianmoooore
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Post Fri Oct 06, 2006 9:11 pm

Before you start burrowing around behind the dash or under the scuttle, pull out relay K7 in the fusebox and link together pins 30 and 87 of its socket with a short piece of wire.
Does that bring the fan to life?
eko
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Post Fri Oct 06, 2006 9:13 pm

Spadge the motor is p1ss to change!
(if it is that)
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gall
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Post Sat Oct 07, 2006 10:48 am

Mine did that to, checked all the fuses and wiring, still no success.

got the multi meter out to find that there wasn't any power at the back of the heater switch. had to use the live feed to the ignition and put a new wire in, now it works.

hope this helps.

gall.
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Post Sat Oct 07, 2006 3:19 pm

Brianmoooore wrote:Before you start burrowing around behind the dash or under the scuttle, pull out relay K7 in the fusebox and link together pins 30 and 87 of its socket with a short piece of wire.
Does that bring the fan to life?
Hi Brian
Yes tried that today and the fans started to work!
What does that indicate please?

Cheers for the rest of your replys fella's :)
SPADGE
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Post Sat Oct 07, 2006 3:28 pm

Just in answer to my own question Brian - i'm guessing bridging those two terminals is basicly doing the job the relay should be doing so am i right in thinking that the problem can only really be the live trigger to the relay from the switch or the relay itself?
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Brianmoooore
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Post Sat Oct 07, 2006 3:49 pm

SPADGE wrote:Just in answer to my own question Brian - i'm guessing bridging those two terminals is basicly doing the job the relay should be doing so am i right in thinking that the problem can only really be the live trigger to the relay from the switch or the relay itself?
You're on the right track. The relay has a ignition live feed to one side of its coil, and is switched by earthing the other side.
Next question is; do your mirrors work, since they are on the same relay, and, do your windows/roof work (doors closed), since they are on a relay that shares the same control circuit.
SPADGE
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Post Sat Oct 07, 2006 3:58 pm

Brianmoooore wrote:
SPADGE wrote:Just in answer to my own question Brian - i'm guessing bridging those two terminals is basicly doing the job the relay should be doing so am i right in thinking that the problem can only really be the live trigger to the relay from the switch or the relay itself?
You're on the right track. The relay has a ignition live feed to one side of its coil, and is switched by earthing the other side.
Next question is; do your mirrors work, since they are on the same relay, and, do your windows/roof work (doors closed), since they are on a relay that shares the same control circuit.
Just checked Brian and no neither the windows or mirrors are working!
The windows will work with the door open though.
If it helps shed any light on what may be the problem, i have just fitted a full OBC in place of the 6 button jobbie that was in their already and so have had all the bottom part of the dash out etc...
Cheers Spadge...
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Brianmoooore
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Post Sat Oct 07, 2006 4:07 pm

Nothing to do with the OBC, but everything to do with the engine conversion.
There's a black/green wire at pin 15 of the C101 engine loom connector socket, which needs to end up on a terminal of your starter motor.
If these things have never worked since the engine conversion, then it's probably wired wrong. If it did work, and now doesn't, check the connection at the starter motor.
SPADGE
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Post Sat Oct 07, 2006 4:13 pm

Brianmoooore wrote:Nothing to do with the OBC, but everything to do with the engine conversion.
There's a black/green wire at pin 15 of the C101 engine loom connector socket, which needs to end up on a terminal of your starter motor.
If these things have never worked since the engine conversion, then it's probably wired wrong. If it did work, and now doesn't, check the connection at the starter motor.
Ahhhh the penny drops :o:
My engine isn't in yet and neither is the engine loom
I thought everything else would work without that being fitted and the engine loom etc were stand alone and only to do with the management and running of the engine itself!
Cheers Spadge..