McMuttley Posted October 4, 2016 Report Share Posted October 4, 2016 You may recall that the brakes lights on olde smokey 'shiney & best buy of the year' stopped working on the way back from the Silverstone Classic in July. Well, having finally got round to checking whether it was the brake switch, it appears that both rear light bulbs had gone - Moss LED's - been in there 15 months and rarely lit. Looking at the wiring diagram and tracing the green or green/white (ish) cables back to the horns (?), I can find no fuse/s in the line, nor had any other fuses in the car gone (horns working, indicators working front and rear, front light working). So I tried one of the olde fashioned bulbs and yup - working ok if held tight (see below). Before I put them back in, should I be looking for a missing short, and if so, where - the cluster of bullets and wires behind the horns is a tad messy, would it be advisable to renew the bullets in case the short is happening due to a loose connection ?? ps - the Moss LED's were such a biatch to get out (tight as heck and needed pliars) that they twisted the lamp off its base and also twisted the rather flimsy bulb housing - deforming them beyond reliability; so I have to order 2 new base plates (must add them to the list of upgrades !) - anyone else experienced this? pps - still haven't found out why all my dash lamps have gone out, but for the one attached to the new ampsmeter - are they all fed off a single point ? Quote Link to post Share on other sites
Lebro Posted October 4, 2016 Report Share Posted October 4, 2016 They are certainly all fed from the panel light switch, but the usual reason for dash lamps not working is the bulb holders not make ing good contact with the bulb, or not being grounded properly. All quite hard to get to without pulling the dash partly out. Bob. Quote Link to post Share on other sites
RogerH Posted October 4, 2016 Report Share Posted October 4, 2016 Hi Austin, here is the wiring diagram http://www.advanceautowire.com/tr24a.pdf The two dash lights are joined together . They could both be blown or the common feed is dicky. Surprisingly there does not appear to be a fuse. You will need to get in behind the dash instrument panel and check for volts etc. As for the LED's see how far you can throw them and fit bulbs If you fit bulbs now they should be in full bloom by early March Roger Quote Link to post Share on other sites
stuart Posted October 4, 2016 Report Share Posted October 4, 2016 One problem with LED`s is they do need full voltage to work so if there was any poor connections back to them and they werent getting full power then they may not have blown as it would be very unlikely for both to blow together. Stuart. Quote Link to post Share on other sites
Graham Harris Posted October 4, 2016 Report Share Posted October 4, 2016 If your beast started life as a left hooker there will be a fuse behind the dash for the instrument lights. Quote Link to post Share on other sites
McMuttley Posted October 4, 2016 Author Report Share Posted October 4, 2016 Thanks Bob - didn't think to check the the wires at the panel light switch Rog - I have that diagram laminated on the garage wall (must add it to the list of valuable extras) - if only it looked so simple in the car ! Graham ... its an authentic UK car I'll have you know (that might add a £10 [€4 today] to the price) - but just in case I'll have a check for a fuse when I go to look at the panel switch Stu - as I remember that the LED's were very stiff to get in, I wonder if they twisted the little springy things at the back so that they were not making contact - canny test now as both LED's broke into pieces coming out (glad I wasn't suck roadside trying to take fragments of bulb out !) Quote Link to post Share on other sites
RogerH Posted October 4, 2016 Report Share Posted October 4, 2016 (edited) In our quest for simplicity and technical advancement we tend to get ourselves in all sorts of TRouble. First there was a bulb. Then somebody invented transistors (semi-conductors) and then along came the LED (in fact the LED was born at the same time as the forst TRanny). The same thing happened with thermionic valves in your radio. The Valve was invented and then along came the semiconductor. I think a very clever blacksmith could make a thermionic valve (come on now, use your imagination). You try making a TRansistor - no way. Stick with bulbs and valves. You will never be short of toast at tea time. Roger Edited October 4, 2016 by RogerH Quote Link to post Share on other sites
RobH Posted October 4, 2016 Report Share Posted October 4, 2016 I agree entirely with your sentiment Roger but actually its pretty easy to make a crude transistor of the point-contact type (akin to the original cats whisker diode). All you need is a couple of pointy wires and a lump of semiconductor material and even the local blacksmith might cope with that. Making a thermionic valve is not so easy. All that glass-envelope-and-hard-vacuum stuff. https://en.wikipedia.org/wiki/Point-contact_transistor I agree wholeheartedly that there is much too much emphasis on complexity these days just for its own sake. There's an awful lot to be said for KISS as a principle (Keep It Simple, Stupid). Quote Link to post Share on other sites
McMuttley Posted October 4, 2016 Author Report Share Posted October 4, 2016 I done a search for thermomonic valves for a TR3A, it seems they are as rare as a steppemottorz for a VW Touareg Quote Link to post Share on other sites
RobH Posted October 4, 2016 Report Share Posted October 4, 2016 That alone is an object lesson in unneccessary complication Austin. Why the hell is there a stepper motor in your diff in the first place? (Sorry for the thread drift) Quote Link to post Share on other sites
RogerH Posted October 4, 2016 Report Share Posted October 4, 2016 (edited) Hi Austin, when the early TR's came out I believe valve radios for cars were all the rage. http://www.ebay.co.uk/itm/Old-Vintage-Ferris-6-Valve-Under-Dash-Mount-Car-AM-Radio-Guard-Mount-Aerial-/351853492846?hash=item51ec1a3a6e:g:56cAAOSw-kdXyRXT Roger Edited October 4, 2016 by RogerH Quote Link to post Share on other sites
McMuttley Posted October 4, 2016 Author Report Share Posted October 4, 2016 That alone is an object lesson in unneccessary complication Austin. Why the hell is there a stepper motor in your diff in the first place? (Sorry for the thread drift) It randomly switches off the diff to disguise the terrible judder that you get in an overweight lump in slow manoeuvres (i must get a human one) I find it perverse that I bought this 'lump' based on TV ads showing it leap sand dunes with apparent ease - yet if just one of the tyres is 2mm out of another - even on flat tarmac - the diff' can't cope ! When I eventually lose it, it will be a tight call as to whether I head off to the support office of Microsoft Office 365 to carry out my terrible deed, or my businesses landlords IT provider, or the nearest VW dealership. One of the side effects of a dodgy stepper motor / actuator thingamy is that it drains your battery. The buztads at VW want to charge me for a third time for re-setting the satnav pin code - which in my view I have already bought from them twice (and which the wife has lost twice!) £30+ plus 1 hours labour !!! Quote Link to post Share on other sites
Steve R Posted October 5, 2016 Report Share Posted October 5, 2016 Hi Austin The dash lamps problem could be caused by the rheostat not working correctly, try turning it up to 11 you could try shorting it out and seeing if that works, but to be honest once you start faffing about behind the dash you'd be best getting a multi meter and go through the circuit logically to find the problem. Steve Quote Link to post Share on other sites
Alec Pringle Posted October 5, 2016 Report Share Posted October 5, 2016 Hi Austin, at least VW gave their unnecessary abomination a realistic name, as in Toe Rag . . . . . . Cheers Alec Quote Link to post Share on other sites
McMuttley Posted October 5, 2016 Author Report Share Posted October 5, 2016 Howdie stranger ! I'll just go and look up what a "rheostat" is and where it is and find the 'how to use a multi-meter' feed on YouTube ! Quote Link to post Share on other sites
Lebro Posted October 5, 2016 Report Share Posted October 5, 2016 Later TR3A's had a rheostat fitted in place of the panel light switch. It is bigger, & thus it's position on the dash was swapped for the wiper switch. So if your panel light switch (knob) is at the top then it is a switch (pull for on), if it is 1 down from the top then it is a rheostat (twist to change brightness). Either way it has 12V going into it, & if off no volts out, or if on either 12V out, or some lower volts out. Bob. Quote Link to post Share on other sites
Steve R Posted October 5, 2016 Report Share Posted October 5, 2016 Howdie stranger ! I'll just go and look up what a "rheostat" is and where it is and find the 'how to use a multi-meter' feed on YouTube ! Howdie yourself, I hope you are well, I'm still around just not been out in the TR much, new clutch, UJ's, rear axle seals, by the time I've got around to doing it the summers gone! Rheostat=Volume control for light! Steve Quote Link to post Share on other sites
McMuttley Posted October 5, 2016 Author Report Share Posted October 5, 2016 Rheostat=Volume control for light! so thats why the panel light has arrows ! - i never knew that - I assumed it was dropping a hint as to what might light up - do I just twist it like a dimmer switch ? Quote Link to post Share on other sites
Lebro Posted October 5, 2016 Report Share Posted October 5, 2016 yes Quote Link to post Share on other sites
McMuttley Posted October 5, 2016 Author Report Share Posted October 5, 2016 Damn, just a pull/push panel switch Quote Link to post Share on other sites
Ben Freer Posted October 5, 2016 Report Share Posted October 5, 2016 Dimmers are so tomorrow! At least you know where you are with an on/off switch ???? Quote Link to post Share on other sites
Don H. Posted October 5, 2016 Report Share Posted October 5, 2016 (edited) Rheostats are easy to find if you want one, Austin. But it really makes almost no difference, especially with your short-timers-syndrome in full effect. I run only a push-pull switch on my car (with a rheostat-style knob, though). The panel lights really don't ever get tooo bright, and they're quite likely to dim to nothing all by themselves. Edited October 5, 2016 by Don H. Quote Link to post Share on other sites
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