Radiator ancilliaries electrical connections

[andyps]

This doesn't get any easier! I've had a good look at the wires now and the black wire from the solenoid goes to the alternator rather than having any connection for the thermo sensor. The wiring diagram suggests a black wire from the voltage regulator (I'm assuming this is the black box on the same block as the fan relay and horn relay) but there are only the green and black wires, although there is a black one connected to earth on the connections.

Sorry to ask for more information but is there a diagram or list which shows what is where on the car in terms of electrical components - schematic wiring diagrams are great but equivalent to navigating above ground using the tube map!

[lancialulu]

Andy I disagree.... If the car is still on its original wiring loom (which I suspect it is) then it is just a case of patience to identify the components on the scematic which relate to the car components and the tediousness of tracing the colours end to end with an ohm meter.  I have attached a clear wiring diagram and code. Simples. Given you seem to have anomolies it is best to tick off a lot more than you had previously thought especially the alternator to regulator as will damage both if incorrect.

[andyps]

Many thanks for your help, it is really appreciated. I do know what you mean about the wiring and it is a case of following things through. Just that when looking at the diagram I have three things mounted on one bracket which are numbers 9, 13 and 34 - they are physically located together but the diagram implies they are a long way apart. When trying to identify components and know where to look for where the end of a wire is likely to be on the car that makes it a lot harder!! I'll get there just struggling with lack of experience of Fulvia layout.

[Richard Fridd]

Perhaps an idea to draw a simplified wiring diagram of only the components being worked upon?

[Jaydub]

Hi Andy, assuming you have a multimeter that measures voltage, ohms etc it should be possible to trace the cables logically.
Simply put, you have a 12 volt feed (via an inline fuse), RED wire, from the starter motor to the Fan Motor. Exiting the Fan motor you still have 12 volts, BLUE wire to terminal 3 on the relay.
Terminal 2 of the relay has a switched 12 volts, RED wire when the ignition is turned on. ( This comes from the Horn relay Terminal 2)
Terminal 4 of the relay, BLUE wire, goes to earth.( Chassis ground) . So when the ignition is turned on, the relay solenoid closes and Terminal 1 of the relay Black wire now has 12 volts which is connected to one side of the thermostatic switch. Once the water is up to the preset temperature, the switch contacts close and the 12 volts goes to earth via the other BLACK switch wire, and turns on the Fan.
You can determine which relay terminals are 2&4 with your Ohmeter because they should have continuity all the time.
Once you have determined 12 volts on the Red wire to the fan motor, earth the other wire ( BLUE) to ground to check fan works, before continuing.
As Tim said it`s a matter of patience and logic. Remember when checking for continuity on wires, ALL wires must be disconnected from their relative components, otherwise you will get false readings.

[andyps]

Thanks for the additional help guys! I'm going away for the next week so will pick this up again when I get back, hopefully will be able to figure it then.

[lancialulu]

Hi Andy, assuming you have a multimeter that measures voltage, ohms etc it should be possible to trace the cables logically.
Simply put, you have a 12 volt feed (via an inline fuse), RED wire, from the starter motor to the Fan Motor. Exiting the Fan motor you still have 12 volts, BLUE wire to terminal 3 on the relay.
Terminal 2 of the relay has a switched 12 volts, RED wire when the ignition is turned on. ( This comes from the Horn relay Terminal 2)
Terminal 4 of the relay, BLUE wire, goes to earth.( Chassis ground) . So when the ignition is turned on, the relay solenoid closes and Terminal 1 of the relay Black wire now has 12 volts which is connected to one side of the thermostatic switch. Once the water is up to the preset temperature, the switch contacts close and the 12 volts goes to earth via the other BLACK switch wire, and turns on the Fan.
You can determine which relay terminals are 2&4 with your Ohmeter because they should have continuity all the time.
Once you have determined 12 volts on the Red wire to the fan motor, earth the other wire ( BLUE) to ground to check fan works, before continuing.
As Tim said it`s a matter of patience and logic. Remember when checking for continuity on wires, ALL wires must be disconnected from their relative components, otherwise you will get false readings.

Just to confirm the rad fan has a 12v fused feed and the relay#9 in the inner wing switches the earth (blue) when the thermo switch (earthed black on one side) earths the relay as it gets to c85C (via a black wire to terminal 1 on the relay#9). The Fan should then come on. In the inner wing is also (or should be) the alternator regulator #13 with red green and black wires. Alongside the ran relay is the horn relay #34 with brown (from fuse box horn supply) black (relay earth) red (horn switch to relay coil) and green (to horns) wires.

It is a bit of a nightmare to get the relay wiring right.... A little story when I acquired my 1600 Sport the previous owner (who was quite competent) had been troubled by his battery going flat regularly. He used the car extensively driving in all weathers and blamed the alternator for not being able to cope with heater wipers lights all on. So he fitted a bigger alternator.... then another battery. It was still a problem when I had the car and I discovered that one of the relays had been wired with the switched supply to the relay coil and the coil activation wire going directly to the device! A simple fix and I then went back to the standard bosch alternator that came with the car....

[Jaydub]

Tim, thanks for spotting in my haste I incorrectly named  terminal 1 as the relay high current side earth instead of terminal 4.
Apologies Andy, for any confusion caused.

[andyps]

Just to confirm the rad fan has a 12v fused feed and the relay#9 in the inner wing switches the earth (blue) when the thermo switch (earthed black on one side) earths the relay as it gets to c85C (via a black wire to terminal 1 on the relay#9). The Fan should then come on. In the inner wing is also (or should be) the alternator regulator #13 with red green and black wires. Alongside the ran relay is the horn relay #34 with brown (from fuse box horn supply) black (relay earth) red (horn switch to relay coil) and green (to horns) wires.

Thanks again, just had a quick look again based on this as apart from the issue I have with the thermo switch wiring I had noticed my voltage regulator didn't match the wiring diagram and your post confirmed it - I only have the red and green wires connected on mine. The only black wire is one that was connected to the mount on it as if an earth, although it does seem it does seem it may connect to the alternator (I've not tested the wire) - where should the black wire connect as I can't see a third terminal. Photo shows what I have, and I know I need to clean the spade connections

[fay66]

Just to confirm the rad fan has a 12v fused feed and the relay#9 in the inner wing switches the earth (blue) when the thermo switch (earthed black on one side) earths the relay as it gets to c85C (via a black wire to terminal 1 on the relay#9). The Fan should then come on. In the inner wing is also (or should be) the alternator regulator #13 with red green and black wires. Alongside the ran relay is the horn relay #34 with brown (from fuse box horn supply) black (relay earth) red (horn switch to relay coil) and green (to horns) wires.

Thanks again, just had a quick look again based on this as apart from the issue I have with the thermo switch wiring I had noticed my voltage regulator didn't match the wiring diagram and your post confirmed it - I only have the red and green wires connected on mine. The only black wire is one that was connected to the mount on it as if an earth, although it does seem it does seem it may connect to the alternator (I've not tested the wire) - where should the black wire connect as I can't see a third terminal. Photo shows what I have, and I know I need to clean the spade connections

Crikey, with the condition of those connectors I'm surprised anything works 
Brian
8227 

[andyps]

I don't know if any of them do work, I've never had the car running although it did start when I looked at it before purchase - 30 years lack of use but dry stored so body is good. Some of the lights and things do work though. I'll clean up all the connections but want to be sure the right wires are on the right connections though.

[fay66]

I don't know if any of them do work, I've never had the car running although it did start when I looked at it before purchase - 30 years lack of use but dry stored so body is good. Some of the lights and things do work though. I'll clean up all the connections but want to be sure the right wires are on the right connections though.

I understand, but why do you think they might not be
Brian
8227 

[lancialulu]

I don't know if any of them do work, I've never had the car running although it did start when I looked at it before purchase - 30 years lack of use but dry stored so body is good. Some of the lights and things do work though. I'll clean up all the connections but want to be sure the right wires are on the right connections though.

I understand, but why do you think they might not be
Brian
8227 

As Brian says they look like they have been there for a helava long time......

[frankxhv773t]

I find a rotary wire brush in a "Dremel" type tool ideal for cleaning up such spade connectors though I have found the Ozito one from B&Q both more affordable and more durable.

[lancialulu]

I find a rotary wire brush in a "Dremel" type tool ideal for cleaning up such spade connectors though I have found the Ozito one from B&Q both more affordable and more durable.

I find spade terminals of that vintage and condition rather fragile. Hence why you see so many poorly crimped replacement terminals on cars. BTW crimping onto oxidized copper wire will give you about the same current carrying capacity as those rusty terminals, leading to more unreliability. Clean the Spades but leave the connectors alone if possible.