tim hunt Posted March 15, 2019 Report Share Posted March 15, 2019 When checking the car over I just noticed a weird issue. If I have sidelights on and operate the headlamp flasher the front side lights, tail lights and all the instrument illumination bulbs are extinguished for as long as I hold the flasher switch back. If I have dipped headlights on and operate the headlamp flasher the same bulbs are extinguished. This also happens if I operate the flasher with the headlights already on main beam. However, if I operate the dip switch to bring the main beams on the side, tail and panel bulbs remain illuminated. Any ideas? It looks like I may be looking for a replacement light switch, any suggestions as to a decent quality source? I had a bad experience with a reproduction 'Lucas' indicator switch a while back. Tim Quote Link to post Share on other sites
Lebro Posted March 15, 2019 Report Share Posted March 15, 2019 It does sound as if the column switch is the culprit. Bob Quote Link to post Share on other sites
MikeF Posted March 15, 2019 Report Share Posted March 15, 2019 Check all the earth connections on affected circuits, MIke Quote Link to post Share on other sites
steamy Posted March 16, 2019 Report Share Posted March 16, 2019 +1 for column switch. Check the riveted contacts on switch are tight and that the contacts have not swiveled round especially on the moving flasher. I had similar problem and turned out to be just that! I resoldered the rivet contact as the replacement switch seemed very poor quality? Regards Ian Quote Link to post Share on other sites
tim hunt Posted March 17, 2019 Author Report Share Posted March 17, 2019 All earths checked out fine. I have bitten the bullet and ordered a new switch and will be checking it out very thoroughly before fitting. At least it won't have to last 53 years as the original Lucas one did, I rebuilt that one twice over the years after the contacts burnt out so it owes me nothing. Fitting relays for dip and main beam solved the problem of burnt contacts. Tim Quote Link to post Share on other sites
steamy Posted March 18, 2019 Report Share Posted March 18, 2019 Hi Tim, My new switch was from one of the well known specialist suppliers and the 'supply' tag had been riveted on 90 degrees out and was in contact with the steering tube causing a direct short which burned out a lot of wiring and killed the alternator (diodes). I was lucky not to lose the car! I couldn't see across the garage for smoke. Remember that the main feed wire is always live even with ignition off so disconnect battery when fitting. Ian Quote Link to post Share on other sites
tim hunt Posted March 18, 2019 Author Report Share Posted March 18, 2019 Thanks for the tip Ian. I always make a point of disconnecting the battery before starting any job of an electrical nature. I first plan to disconnect all five leads from the old switch from their bullet connectors then I will connect the corresponding leads on the new switch and try out its functioning. If satisfied I will remove the old switch and carefully compare how the leads are connected to both switches and ensure that there is no risk of a short from the new switch to the column cowl when fitted. Tim Quote Link to post Share on other sites
tim hunt Posted March 24, 2019 Author Report Share Posted March 24, 2019 An update. I bit the bullet and ordered a repro switch. Unfortunately it was poor quality, it checked out OK electrically and the flash and sidelight functions were positive. However, on moving the switch further it would locate in an intermediate position where no contact was made before moving further to operate headlights, the action felt horrible. The seller readily agreed to a return for full credit. One problem I have had for some time with the existing switch is that the threads in the body are stripped and consequently the switch could not be secured to the column cowl and when operating the flasher the whole switch would move. I remembered that around 30 years ago I had helped myself to a column switch from a 13/60 Herald that had been abandoned at the roadside and was being stripped for parts. I examined this and although the connections are not the same as on the 4A switch I noted that the outer housings are and the securing holes on the Herald housing had perfect threads. I took out my existing switch, re-soldered all the contacts and swapped the housing for the Herald one. I re-connected the five wires from the switch and found that it operated perfectly, it also clamps tightly to the column cowl and feels really nice to operate again. Problem solved. Lucas 'Prince of Darkness' comes in for a lot of stick but I reckon the moral here is that when possible it is better to restore an original switch than go for a repro part of dubious quality. Tim Quote Link to post Share on other sites
TorontoTim Posted March 27, 2019 Report Share Posted March 27, 2019 On 3/24/2019 at 7:41 PM, tim hunt said: Lucas 'Prince of Darkness' comes in for a lot of stick but I reckon the moral here is that when possible it is better to restore an original switch than go for a repro part of dubious quality. Tim This is a key statement! Quote Link to post Share on other sites
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