Lancia Motor Club

Model Technical and Interest => Fulvia => Topic started by: Fulviartist on 04 October, 2020, 12:38:51 PM

Title: Fulvia coupe s2 lights
Post by: Fulviartist on 04 October, 2020, 12:38:51 PM
Having an odd problem with the side lights and low beam on my S2 1600HF. Solenoid clicks when I move switch but no lights except for main beam. Fuses all good. Any ideas? Otherwise running fine.

Title: Re: Fulvia coupe s2 lights
Post by: Jaydub on 04 October, 2020, 03:07:15 PM
Hi Chris, fuses might look OK but worth removing and cleaning contacts. Always difficult to diagnose electrical faults from afar. There are 3 relays in the circuit. side lamp relay feeds main beam relay which is a change over relay between Dip and Main beam. So it`s a matter of checking all connections including earths and working the lighting stalk switches on and off for bad contacts which are the earth circuits for all the relays, and disconnecting/reconnecting multi plugs.
Good hunting.

Title: Re: Fulvia coupe s2 lights
Post by: Fulviartist on 04 October, 2020, 03:30:28 PM
Thanks Jay, yes your reply makes sense. I've already gone through the fuse. It was odd they all went at once so I think the relays and their earths are the most likely cause. At least the fuse compartment is relatively easy to strip down and clean up, as is the lighting stalk. I'll let you know how I get on. Thanks again.

Title: Re: Fulvia coupe s2 lights
Post by: Fulviartist on 08 October, 2020, 07:31:41 PM
Hi again John, I said I would update you. I went through the fuses, all good, then checked the relays. I opened the black relay and found a burnt out wire. Not sure of the rating but it is the bare wire that connects the no.73 bayonet (for the 1.5mm red wire) to the top of the magnetic switch. See attachments. I soldered in a replacement but it burnt out when tested. So not sure if I have a short somewhere or the wire was the wrong rating. Any ideas?

Title: Re: Fulvia coupe s2 lights
Post by: davidwheeler on 10 October, 2020, 09:47:26 PM
To burn out a wire of that thickness you must have a short.

Title: Re: Fulvia coupe s2 lights
Post by: Jaydub on 11 October, 2020, 03:44:04 PM
Hi Chris, the 2 bare wires to the top of the contacts on the left and right are not burnt out. That is the way they should be. Connector 73 is the feed wire to Fuse 1& 2,(White wire) connector 49, when the contacts are closed. Fuse 1&2 are the feeds to the side lights. The relay is operated by the slide switch on the lighting stalk which earths the relay. Make sure that the Red wire to spade connector No.1 on the relay has 12 volts from the ignition switch via the connection on Fuse 8. Relay connection 56b ( yellow wire) goes to the main beam relay Pin2.

Good Luck


Title: Re: Fulvia coupe s2 lights
Post by: Fulviartist on 12 October, 2020, 06:34:34 PM
That's very helpful John. I know there's a short when the contacts from 73 to 49 are closed which makes me think the fault is between this relay and fuses 1 &  2. But as I can't find any fault in the wiring and the side lights work when I earth the brown wire in the loom from the white connector above the steering column (as per Omicron's lighting fault finder) I'm thinking one of the other 2 fuse box relays may be the source of the problem. Your tips will certainly help source the gremlin!

Title: Re: Fulvia coupe s2 lights
Post by: Jaydub on 12 October, 2020, 08:31:38 PM
Hi Chris,

Apologies on the comment on my last post. I was in a rush and stupidly didn`t notice that the bare wire in the relay had in fact burnt out and wasn`t connected to anything!
What is puzzling though is the fact that you said the side lights worked when you earthed the brown wire in the white connector. That is what the slide switch does, or should do. It earths the brown wire to the stalk of the switch. In doing so it closes the contacts between 73 and 49 and then you say it burns out the bare wire. Once that wire is burnt out , there is no power to Fuses 1&2 so the side lights cannot work. Also that would mean no power to the yellow wire 56b, which feeds the main beam relay (32) pin 2 and therefore no main beam lights but you said they are working??   If both of those are working with a burnt out wire, there has to be another source of power to those circuits somehow?
Can you verify that is happening.


Title: Re: Fulvia coupe s2 lights
Post by: Fulviartist on 15 October, 2020, 12:05:03 AM
Thanks John for taking such an interest. I have checked the thin red wire from fuse 8 and it reads 12v as it should. The first photo shows the original burnt out wire, the last shows a replacement burnt out wire which was too thick and burnt out when I closed the points between 73 to 49.

Since the photo I have soldered in a replacement wire of the correct spec. I then found by earthing the brown wire, the side lights work, but the points 73 and 49 didn't close as I expected. Very odd.  I couldn't make the dip beams work by connecting the grey wire to the black & white at the same white junction box next to the steering column as I used to earth the brown wire. Nor would the main beams when I connected the green wire to the last two wires. Although the main beam had been working normally originally. The fact the side lights work in this test tells me the short is not in the loom to the sidelights, more likely at the fuse box or in the dip beam relay?

I have also removed and cleaned all the connections on the indicator stalk in case this was where the short was. I have now replaced this and will check all the wires from the  fuses again.  I haven't had time to test any more for a couple of days but will have another go this weekend if not before.

Title: Re: Fulvia coupe s2 lights
Post by: Jaydub on 15 October, 2020, 04:06:33 PM
Hi Chris, as I previously said, the slider switch earths the Brown wire to the lighting switch body, steering column etc. This connects to Pin 2 of the side lamp relay and in turn closes the relay solenoid on  the low current side of the relay. The solenoid will only work if there is 12v on Pin 1 from Fuse 8  (from ignition switch black wire to Fuse 8 and Red wire to the relay)  and the Brown wire is earthed.

The other relay connections are....
Pin 73.    Constant 12v from Fuse 7 ( fed from starter connection Thick Red )

When Brown is earthed and the low current solenoid closes, it connects 73  (high current) to Pin 49  ( White wire to Fuse 1) and thence to side lights.
Correspondingly, 73 is connected to Pin 56b,  Yellow wire to Pin 2 on the Main Beam Relay.
Correspondingly   the earth Pins 56a  ( twin Black wires, one directly to earth and the other to Cigar lighter) & 56  ( White/Black wire) are connected internally and this provides the earth path for the Grey and Green wires on the lighting switch.  Light switch pulled down, Grey is earthed to White/ Black and operates the dip beam outer lamps relay (30).
Switch pulled towards you, Green wire is earthed to White/Black and operates the Main beam outer lamps relay (32).
Obviously relays (30) & (32) need their relevant correct connections which I can tell you another time if you wish.
Good Luck.

Title: Re: Fulvia coupe s2 lights
Post by: Jaydub on 15 October, 2020, 07:22:32 PM
Sorry, had to break off to do something else.
In summary, if the sidelamps are working but the relay solenoid isn`t and the contacts aren`t closed, Fuse 1 is getting a feed from elsewhere other than the White wire from relay pin 49.
Likewise, if the contacts aren`t closing and connecting pins 56 & 56a, then the White/Black wire will not provide an earth path for the Grey & Green wires, as you found out when you joined them at the white junction block.
Possibly the braided wire in the relay is blowing because the Yellow wire 56b going to the Main Beam relay is shorting ,or the relay itself is.

Keep in touch.


Title: Re: Fulvia coupe s2 lights
Post by: Fulviartist on 15 October, 2020, 09:12:04 PM
That's all really helpful. I think you have probably diagnosed it. I'll look at everything again at the weekend and let you know what I unearth (sorry, couldn't resist! There I go again . . .).

Title: Re: Fulvia coupe s2 lights
Post by: Fulviartist on 17 October, 2020, 07:47:12 PM
All sorted!

Many thanks John for your advice and quick replies to my posts. I have a much clearer concept now of how Fulvia wiring works having followed through on your suggestions. Having had Fulvias for over 45 years, you would think I would be an electrical expert . . . but I've never had any relay problems before. I can rebuild a starter motor or fix the earthing on a faulty lamp and I have sorted the odd alternator issue. So I'm only expert in the things I've had to fix. Same goes for the mechanics, brakes or cooling system.

The original fault was caused by the wire from the fuse box to the fog lamp relay above the steering column becoming chafed near the column and shorting the main relay, burning out the braided wire as you saw. Also the switch on the light stalk was not making perfect contact. So when I repaired the braided wire it was burning out each time when I earthed the brown wire. I have fitted a new inner lamp wire from the fuse box and cleaned up the contacts in the light stalk and everything works perfectly.
Will be good to take my HF out for a spin tomorrow.

Is your HF on the road? I noticed from your earlier posts you mentioned you would be taking it off the road in June.