Fulvia Coupe S1 dash warning lights

[motoloco]

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 don’t.

The red and black wire that feeds all three is live when the ignition is on, so I can’t understand the problem. Of course, they worked fine before disassembly......

Any ideas?

Thanks

Nick

[frankxhv773t]

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?

[motoloco]

Thanks Frank, but I’ve now tried a spare cluster and that doesn’t work either...

[neil-yaj396]

Bad earths?

[motoloco]

Bad earths?

That was my original thought, but everything appears clean and making good contact. There are six warning lights, three work and three don’t. Both indicators and main beam are fine, choke, handbrake and dynamo aren’t.

[nthomas1]

The three lights that are working share a common earth path on the circuit board. The ones that aren’t 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!

[motoloco]

The three lights that are working share a common earth path on the circuit board. The ones that aren’t 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 haven’t had chance to look at it this week, but battle will resume later today....
Cheers
Nick

[lancialulu]

It would be very surprising if all of those 3 independent "earths" has failed in some way.

[motoloco]

It would be very surprising if all of those 3 independent "earths" has failed in some way.

Hi Tim
I agree and I’m probably missing something obvious, but each of the three bulb holders is live. There isn’t, or I can’t see, a common connector block for the earths that could be at fault, so the search continues.

Nick

[lancialulu]

It would be very surprising if all of those 3 independent "earths" has failed in some way.

Hi Tim
I agree and I’m probably missing something obvious, but each of the three bulb holders is live. There isn’t, or I can’t 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......

[motoloco]

After much head scratching, I’ve 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.

I’ve reinstalled conventional bulbs and all is fine. That’s a bundle of hours I won’t get back!

Thanks for everyone’s suggestions.
Nick

[lancialulu]

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....