BernardSG 13 Posted December 29, 2020 Report Share Posted December 29, 2020 Hello everyone! Eventful drive yesterday : it started raining heavily and got quite dark. I switched on the lights, but after a couple of minutes, they retracted on their own (I believe the lights were still on; but the pods went down). I couldn't bring them back up right away. I tried again a minute later or so and this time it worked. Not for long though. I tried again today in full daylight, dry weather. The same thing happened. The pods don't stay up for long. Any idea of what it could be? A faulty relay? Cheers! Bernard Quote Link to post Share on other sites
rjwooll 220 Posted December 30, 2020 Report Share Posted December 30, 2020 You’re probably in the right area. I believe the relay operates a solenoid which controls the vacuum to the headlamp motors. As there is no vacuum when the lights are up, then the solenoid must be opening to allow vacuum to be admitted, which could easily be caused by a faulty relay, or something like a bad earth. However I have electric headlamp motors which present an entirely different set of problems, so my speculation is theoretical rather than practical! Cheers, Richard Quote Link to post Share on other sites
BernardSG 13 Posted December 30, 2020 Author Report Share Posted December 30, 2020 Thanks Richard! I'll have to keep investigating. During a short drive today, I realized that the headlights not only close on their own, but after while they reopen on their own as well... And then its an endless cycle. Open, close, open, close... I suspect its something to do with the voltage drawn from the battery : with both headlights and aircon on, I see the volts going down... Then the lights close, Voltage slowly goes back up, and after a while the lights open... I'll have to retry without the aircon, to see if I face the same symptoms. Cheers! Bernard Quote Link to post Share on other sites
Tony D 63 Posted December 30, 2020 Report Share Posted December 30, 2020 Can you confirm your car still has the vacuum operated pods? Has it been retrospectively fitted with motors? Route cause will likely be quite different depending on whats driving them ( Vacuum or electrical magic) Tony Quote Link to post Share on other sites
BernardSG 13 Posted December 30, 2020 Author Report Share Posted December 30, 2020 Hi Tony, They're still vacuum operated. I don't think there is any major leak as the pods stay in the closed position for over a week when the car is not driven. Thanks! Bernard Quote Link to post Share on other sites
rjwooll 220 Posted December 31, 2020 Report Share Posted December 31, 2020 Definitely worth cleaning up the electrical connections and earth to the relay/solenoid. Problems in this area will magnify the effect of any voltage variations, which the unit should be able to tolerate, unless the solenoid itself is getting lazy. cheers, Richard Quote Link to post Share on other sites
Tony D 63 Posted December 31, 2020 Report Share Posted December 31, 2020 Sounding like a relay problem to me. There is one solenoid for each pod, so if both pods are dropping, it means they both loosing the 12 V signal simultaneously. Very unlikely therefore to be a dodgy contact at the solenoid. Tony Quote Link to post Share on other sites
BernardSG 13 Posted January 2 Author Report Share Posted January 2 Thank you both. This would be one of the relays under the steering column/driver footwell, right? Any hint as to how to identify which one? Quote Link to post Share on other sites
rjwooll 220 Posted January 2 Report Share Posted January 2 Hi Bernard, I’ve looked at the wiring diagram you helpfully posted! I can’t see any relays in the headlamp circuit, and it looks like the solenoid valves are powered directly once the headlamps are switched on. My guess would be a dodgy earth as they both behave the same way and use a common earth, according to the wiring diagram. There is also something called a thermal interrupter that looks as though it protects against circuit overload so I suppose the problem could be there but I have no idea where you might find it! If you trace the vacuum pipes to the pods they should lead you directly to the solenoid valves. On series 2 cars the earth point is on the offside inner wing - don’t know if S1s used the same arrangement. Cheers, Richard Quote Link to post Share on other sites
black eclat 61 Posted January 2 Report Share Posted January 2 Does this occur low beam and high beam? Or just low beam? And have you confirmed if lights stay on when the pod closes? Quote Link to post Share on other sites
BernardSG 13 Posted January 3 Author Report Share Posted January 3 Hi eveyone, thank you very much for the new pointers! First, low beam vs high beam : I have to admit I hadn't checked in High beam. I was just using low beam when I had these open/close cycles. Then, the thermal interruptor. I didn't find much info about it on the forum, but a Wikipedia page mentioned the following : Thermal switches are included in some light fixtures, particularly with recessed lights, where excessive heat is most likely to occur. This may lead to "cycling", where a light turns off and back on every few minutes It made me quite certain it was the culprit, as it really corresponds to my symptoms. But then I took it for another drive. And today, the behavior was different. The pods remained open throughout, but the lights are off. If I switch to the high beam, everything is fine (lights are on, pods remain open) which left me puzzled. Why does is the problem only for low beam? I tried swapping the fuses (high beam vs low beam), but no difference. I checked the wiring diagram, and mine being a late serie eclat (1979), it does have a relay after the thermal sensor (see file attached) I guess I'll try to find this thermal switch and the relay and check the connections... Cheers, Bernard Quote Link to post Share on other sites
Solution black eclat 61 Posted January 4 Solution Report Share Posted January 4 Bernard, The relay you have circled is to operate the vacuum valves. This must be ok if you dont have any issue when on high beam (the pods still need to be up) It sounds to me that the issue is the light switch (high / low beam) on the steering column. This switch can gunge up over time leading to erratic voltage which would manifest itself as you describe with pods going up and down. The moving contact can also melt if larger wattage lamps are fitted. Most likely it just needs to be stripped and cleaned. That would be my recommendation. Michael. 1 Quote Link to post Share on other sites
BernardSG 13 Posted January 5 Author Report Share Posted January 5 Thank you Michael for your help, I had not thought of this. It could indeed explain why only the low beam don't work. I hope it's not too difficult to get to that switch! Quote Link to post Share on other sites
BernardSG 13 Posted May 5 Author Report Share Posted May 5 Hi everyone! I'm finally in a position to close this topic: I followed Michael recommendation and had a look at my indicator stalk. It was indeed partially melted. Ordered one (plus a bunch of other bits) from SJ and replaced it. Everything now works! I take this back: everything related to the lights now works ;) At the same time, I realized that the stalk on mine was not the original version , so the replacement also addresses that. Thanks all for the support, moving on to other issues now! Cheers! 1 Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.