Xantia 1.9TD 1999

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 13:13

No sign of the fan(s) cutting in.. ran the temp up to approx 95c and nothing... a/c engages, green fluid with bubbles in sight glass... but no cooling fans. I have a multimeter but require info on how do do checks

Clogzz · Unread post by **Clogzz** » 28 Apr 2006, 13:23

If you pull out the ‘left fan relay’, and the middle one too, and bridge contacts 3 & 5 on the left fan relay socket, and contacts 3 & 4 on the middle relay socket, both fans should go to the low speed with aircon turned on.
Like that you also have access to the contacts for measuring the voltages, or better: to test with a lamp.
There should be 12 Volts on the left relay bridged contacts, and 6 Volts on the middle one.
While you’re there, check for 12 Volts on pins 1 & 2 of the left relay socket, and there should be no voltage on pins 1 & 2 of the other 2 relays.

Edit 12:26 PM: Sent this post before I saw your last.

Put multimeter on DC 12 Volts range, or higher.
Black negative wire to earth like battery negative or bare metal.
Red positive wire to relay socket contacts.

Same, but easier with the test lamp, no polarity or red or black wires.
The lamp should light bright on the left relay socket, and dim on the middle relay socket.
If the lamp is out, or zero volts on the middle socket, then the left fan, or its connection is open.
If there’s 12 Volts or full lamp brightness on the middle socket, then the right fan, or its connection is open.

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 13:47

brilliant, thanks i'll have a go now

Clogzz · Unread post by **Clogzz** » 28 Apr 2006, 14:27

It’s about 11:30 PM here now, feeling dizzy after a long, scruffy day on the job.
Going

If the engine gets hot, you can always pull the plug off the brown sensor to give it a cool blast.
Never for too long, because it’s not the moment to wear the brushes.
Back tomorrow evening.
Best of luck !

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 14:27

Well! I've got the relays out, but I can't see any 3&5 or 3&4 marked on the sockets or the relays.... I did say I wasn't good at electrics

Clogzz · Unread post by **Clogzz** » 28 Apr 2006, 14:36

The numbers are according to the map.
If you can see or reach, 3 & 4, and 3 & 5 are thick wires, while 1 & 2 will be thin ones.
The middle relay will have 3 thick wires.

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 14:41

Found the numbers written on the old relays.. except that the middle relay has no number 4 anyway I connected 3+5 on the left relay and 3+5 on the middle relay and the left fan started running (s**t myself) and there is 12v on the centre relay!!

Clogzz · Unread post by **Clogzz** » 28 Apr 2006, 14:46

Should be the left relay that has only 4 pins.
Is the 12 V on the middle socket on a thin or thick wire ?
The thin ones are for the relay coil, the thick ones for the fan current.

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 14:50

As you stand looking a the front of the car.... the black L/H relay has 5 pins the R/H green and Ctr green relays have 4 pins (am I keeping you from your bed?)

Clogzz · Unread post by **Clogzz** » 28 Apr 2006, 14:56

Are there then 2 sockets with only 4 contacts, and the middle socket has 4 contacts ?
Can you see the number and thickness of the wires behind the sockets ?
The black 5-pin relay must go where there are 3 thick wires.
Not keeping me from bed, but still would do well to go lying down soon.

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 14:59

Thats correct.. the L/H relay Black/Purple has 5 pins

No I cant see behind the plugs unfortunately it seems to be an enclosed box

Clogzz · Unread post by **Clogzz** » 28 Apr 2006, 15:06

Are there 5 contacts in the left socket, and 4 in the other 2 ?
Are these the new relays, and the old ones were all 3 the same colour ?
There should be 5 contacts in the middle socket, and that's where the purple would go.

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 15:11

That is correct... you cant mix the l/h relay with the other two... it wont fit and the old l/h relay was black and the new one is purple... the other two were and are green.

Clogzz · Unread post by **Clogzz** » 28 Apr 2006, 15:24

Well, that looks like the middle, or change-over relay is then the purple one, and lives at the left, contrary to what the map shows.
And so, the 'left fan relay' will be the one that's got 12V on 3 pins.
And the 'right fan relay' will be the one that's got 6V on one pin, when everything is normal, or nothing when faulty.

Gone

f00lzz · Unread post by **f00lzz** » 28 Apr 2006, 16:30

Ok thanks for your help..... i'm completely in the dark now