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Gauge lights?

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OregonTR4A

OregonTR4A

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Anybody have any idea on where I start?
My tach and speedo work fine but the 4 others do not light up. There are new bulbs in them all and still no worky? The rheostat works on the tach and speedo.

On a side bar my horn quit (not at the same time). I have pulled out the horn button but it appears everything is in order.
Any suggestions would be appreciated.

thanks
 
Idea;...Probable a simple ground problem,or ON spitfires its the middle fuse(dash lights),or the reostat dimmer connections....Always use British spec fuses 20amp(usa)35amp Brit....17.5amp blow.
Helpful?.....Usually an old Brit car has been modified(from po to po) over&over so its anyones guess.
Ken....Of course LordLucas is NOT dead until the fat lady gets electrocuted. :savewave:
 
I'd pop one of the bulb holders out, and probe the center contact with a well-grounded test lamp. If it lights, then either the bulb is bad, or it wasn't making contact in the socket, or the socket wasn't getting grounded.

If it doesn't, check at the rheostat to be sure all the RW wires are connected. If so, must be a broken wire somewhere, possibly inside the insulation where you can't see it. You can try probing through the insulation with the sharp point of the test lamp; or just run a new length of wire from the rheostat past the problem spot.
 
I had a bad fuse in my TR7 DHC that caused some of the lamps in the dash circuit to light and some not to light. I could measure 12 volts on both sides of the fuse and measured 0 ohms across the fuse. I had tried cleaning the contacts in the fuse panel and polishing the contacts on the fuse itself but neither helped. Replacing the fuse cured the problem. I figured it out by hooking a 12 volt power supply directly to the RW wire at the rheostat and all lamps worked.
 
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