Author Topic: light switch strange behaviour  (Read 388 times)

Offline a101960

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light switch strange behaviour
« on: 09.04. 2015 16:23 »
During last years MOT the tester mentioned in passing that when the rear brake was operated the parking light lit up. Obviously a bad earth we both thought. I subsequently spent a long time going through the wiring, and I was unable to trace and rectify the problem. I then discovered that if I applied a little extra leverage to the light switch knob when it was in the off position the parking bulb did not light up when I operated the rear brake. On examining the switch it was apparent that there was quite a lot of play present which led me to believe that the cause of the problem was a faulty switch. Anyway I bought a new switch, and wiring harness, and guess what? The exact same problem is still there. Once again a slight bit of extra pressure on the light switch when it is in the off position resolves the problem. It would seem that pattern switches are definitely not precision made items! Has anyone else had this problem? Or have I just been unlucky having two switches that malfunction? By the way both the parking light, and the rear light are fitted with LED lamps could that make a difference do you think?
John

Offline duTch

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Re: light switch strange behaviour
« Reply #1 on: 09.04. 2015 16:44 »

 
Quote
The exact same problem is still there. Once again a slight bit of extra pressure on the light switch when it is in the off position resolves the problem. It would seem that pattern switches are definitely not precision made items!

  ..on the contrary- it was obviously accurately made with the same with inbuilt 'faults' as the original.... *smile*, mine does it at the other end when the headlight is on  *eek*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
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Offline bsa-bill

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Re: light switch strange behaviour
« Reply #2 on: 09.04. 2015 17:08 »
Ha I was thinking along the same lines as duTch

From memory all the contacts on those switches are to be seen under a plate that's under the knob, any play or wobble in that area could produce strange results
All the best - Bill
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Offline a101960

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Re: light switch strange behaviour
« Reply #3 on: 10.04. 2015 11:10 »
Quote
..on the contrary- it was obviously accurately made with the same with inbuilt 'faults' as the original.... *smile*, mine does it at the other end when the headlight is on  *eek*
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