Cooling fans not working

MikeT · Unread post by **MikeT** » 10 Jan 2009, 15:27

Thanks everyone, I've now established both fans are working (slow speed) by jumpering the Left Fan Relay socket Pins 3 & 5. I've also checked every fuse and they're all present and correct.

To recap, all 3 relays, all fuses and both fans are in working condition. The temperature gauge sender reacts normally via the instrument gauge.

+12v Read at;-
[LEGEND; L= Left Fan Relay, R= Right Fan Relay, C= Change Over Relay]
Ignition OFF
R Pin3
L Pin3

Ignition ON
C Pin1
R Pin1 & 3
L Pin3

Ignition ON and Temp Sender disconnected
C Pin1
R Pin1 & 3
L Pin 3

Damn, I forgot test the earths

KevMayer · Unread post by **KevMayer** » 11 Jan 2009, 00:32

We're getting closer to the problem. I'm sure we'll soon have it sorted.

You're still missing a live (+ve) on pin 1 of your left hand relay. This should be live even if the earths are poor.

Can you test if you have volts (+12 ) on fuse F14.

From the diagram, fuse F14 is supplied by fuse D in the BMF1 unit. Fuse D may be the problem.

hirsty · Unread post by **hirsty** » 11 Jan 2009, 17:08

Fuse 14 on the dash fuse box for mine says Fuel Injection ECU /air conditioning. Is this the one ?. Is BMF1 the engine bay fusebox ? If not where is it ?

Thanks

addo · Unread post by **addo** » 11 Jan 2009, 21:11

Yes, BMF1 is the engine bay fuse box. Under the dash is BF00.

Sound like acronyms which may be less than polite!

hirsty · Unread post by **hirsty** » 11 Jan 2009, 22:35

Thanks addo. After spending several weeks sorting the electrics for heater fan, dashboard lights, poor headlight connection, radio fuse, gear selector solenoid, interior lights and others, I can think of several rude acronyms !!!

MikeT · Unread post by **MikeT** » 12 Jan 2009, 10:15

As stated earlier, I've checked all fuses in both boxes but how do I tell which is Fuse A and which is Fuse D? Looks like I need to check the feeds to the fuses next

hirsty · Unread post by **hirsty** » 12 Jan 2009, 11:37

According to my handbook, looking at the engine fusebox from the front of the car, fuses A and D are high voltage fuses to left of box and are vertical in two rows. Top row right is fuse A (60A) and top row left is fuse D (40A). Hope this helps.

Clogzz · Unread post by **Clogzz** » 12 Jan 2009, 14:31

Hi Mike,

Just as per hirsty’s post … pictures of fuses A & D, 60A and 40A.
Fuse A of 60 Amps is OK because it feeds most of the ignition switch functions, including the high fan speed switching, which works on one side.

Between fuse D and F14 under the dash is what looks like a zigzag component that the BoL calls a shunt.
The shunt is a bigger fuse, upstream of smaller fuses, without specifying the number or value, but is 2V NR in box E of the location diagram.

You must have 12V on pin 1 of 1502 even with the key out; from the battery through fuse D first, then through the shunt fuse under the dash, and lastly through fuse F14, which is 13V OR.

MikeT · Unread post by **MikeT** » 12 Jan 2009, 15:27

Of course! The heavy-duty engine bay fuses are alphabetically labelled, doh!

It's raining here so didn't re-test them again but instead located a "shunt" fuse under the dash and that's fine. Then tested for 12V at F14 and that's fine so the fault seems to lie between F14 and the fan relay? Are we sure F14 is the correct fuse as it's only described as serving ""Injection ECU - Refrigeration Cut-Off Relay"? before I look elsewhere?

hirsty · Unread post by **hirsty** » 12 Jan 2009, 15:58

Mine says the same and I cannot find any reference to cooling fans on any of the other fuses listed.

Where did you find the under dash shunt Mike ?

Clogzz · Unread post by **Clogzz** » 12 Jan 2009, 16:41

Are we sure … ?

No, we’re not.

There are all sorts of ‘evolutions’ in the transition to the Mk II.
It’s very likely to be a 5A fuse, called ‘cooling fan’, and even be under the bonnet.

hirsty · Unread post by **hirsty** » 12 Jan 2009, 17:06

Checking my trusty handbook, the fuses under the bonnet contain two marked cooling fan. Fuse 3 (30A) and Fuse 5 (5A). See Clogzz picture for location.

Keith

MikeT · Unread post by **MikeT** » 12 Jan 2009, 18:55

Ditto, according to my handbook - nothing under the dash but two in the engine bay.

MikeT · Unread post by **MikeT** » 14 Jan 2009, 10:57

I can now confirm all earths to Pin2 are good also but that was to be expected having found a faulty +12v feed already. Tracing wiring isn't a job I have much success with, any tips for finding this break, considering we're not 100% sure the given wiring diagrams are that of my car?

Unread post by **CitroJim** » 14 Jan 2009, 12:22

MikeT wrote: considering we're not 100% sure the given wiring diagrams are that of my car?

Mike, what's the RP number of your car? With that I can then post up the right applicable diagrams.

I'll bet a bob that the duff wire is in the loom that runs under the rad and across the front of the car...