Lancia Motor Club

Model Technical and Interest => Fulvia => Topic started by: motoloco on 05 July, 2020, 06:40:39 PM



Title: Fulvia Coupe S1 dash warning lights
Post by: motoloco on 05 July, 2020, 06:40:39 PM

I'm reassembling the dash on my S1 Fulvia Rallye 1.3S and have a problem with the warning lights. Both indicator and main beam warning lights work, but choke, Dynamo and handbrake donít.

The red and black wire that feeds all three is live when the ignition is on, so I canít understand the problem. Of course, they worked fine before disassembly......

Any ideas?

Thanks

Nick


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: frankxhv773t on 06 July, 2020, 10:25:13 AM
Might this be the same issue with corrosion on the printed circuit that Norm Thomas has just written up in his low S2 rebuild thread?


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: motoloco on 06 July, 2020, 12:48:40 PM
Thanks Frank, but Iíve now tried a spare cluster and that doesnít work either...


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: neil-yaj396 on 08 July, 2020, 07:48:54 AM
Bad earths?


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: motoloco on 09 July, 2020, 09:37:00 AM
Bad earths?

That was my original thought, but everything appears clean and making good contact. There are six warning lights, three work and three donít. Both indicators and main beam are fine, choke, handbrake and dynamo arenít.


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: nthomas1 on 09 July, 2020, 10:36:37 AM
The three lights that are working share a common earth path on the circuit board. The ones that arenít are linked by a different path that is shared by alternator light, handbrake and fluid level light, choke light and fuel level light. The path originates at the post where the Fuse 9 feed is connected. That post may be corroded. Or, the path on the circuit board might be corroded. The path is very thin where it runs along the lower edge of the board and along the top edge of the board. It does not take much corrosion to block these paths.

All of the above assumes that your series 1 panel is the same as my series 2!


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: motoloco on 11 July, 2020, 09:11:19 AM
The three lights that are working share a common earth path on the circuit board. The ones that arenít are linked by a different path that is shared by alternator light, handbrake and fluid level light, choke light and fuel level light. The path originates at the post where the Fuse 9 feed is connected. That post may be corroded. Or, the path on the circuit board might be corroded. The path is very thin where it runs along the lower edge of the board and along the top edge of the board. It does not take much corrosion to block these paths.

All of the above assumes that your series 1 panel is the same as my series 2!

Hi Norm
The S1 is different in that the warning lights and small dials are in one cluster and the speedo and rev counter are individual items. You are right in that the three offending lights share a common power feed (bizarrely the power goes to the outer part of the bulb holder and the central wire goes to a switched earth), but that seems ok. The connector for the loom plug is riveted to the printed circuit on the back of the cluster, so not easy to access, but the circuit seems ok when tested with a meter.
I havenít had chance to look at it this week, but battle will resume later today....
Cheers
Nick


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: lancialulu on 11 July, 2020, 04:00:46 PM
It would be very surprising if all of those 3 independent "earths" has failed in some way.


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: motoloco on 12 July, 2020, 12:40:50 PM
It would be very surprising if all of those 3 independent "earths" has failed in some way.

Hi Tim
I agree and Iím probably missing something obvious, but each of the three bulb holders is live. There isnít, or I canít see, a common connector block for the earths that could be at fault, so the search continues.

Nick


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: lancialulu on 12 July, 2020, 01:35:26 PM
It would be very surprising if all of those 3 independent "earths" has failed in some way.

Hi Tim
I agree and Iím probably missing something obvious, but each of the three bulb holders is live. There isnít, or I canít see, a common connector block for the earths that could be at fault, so the search continues.

Nick
Nick the lights are triggered by their own earth i.e. alternator sinks current when not charging......


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: motoloco on 12 July, 2020, 02:38:27 PM
After much head scratching, Iíve solved the problem, but not the mystery.

All of the warning lights, including the indicators and main beam which still work fine, are LEDs, which worked ok before.
At some point during the removal of the cluster and re-installation, the LEDs for choke, Dynamo and handbrake, all blew. The battery has been disconnected, apart from when testing, so it is a mystery.

Iíve reinstalled conventional bulbs and all is fine. Thatís a bundle of hours I wonít get back!

Thanks for everyoneís suggestions.
Nick


Title: Re: Fulvia Coupe S1 dash warning lights
Post by: lancialulu on 12 July, 2020, 09:03:13 PM
LED are polarity sensitive and I doubt work anyway with alternator so using ordinary bulbs is best solution. I only use leds (green) for indicator warning and put up with dim other lights. Main beam warning in led would in any event be too distracting in my opinion....