Hi All:

1986 XJ6 series 3 base

Today's mystery is a consequence of me trying to put in some LED dash panel lights. Why the bulbs are different for the left and right turn signal is beyond me, Anyway - I change the speedo light -- all good. I change the left turn signal light and all good. I change the tach bulb and the right turn signal and those two do not work. I change it back to bulbs - no go. Just the tach light and the right turn signal. Externally, both left and right signals work fine and sound normal. No other lights seem to be affected. As I'm writing this and thinking like an Englishman (or what I think an Englishman would think like). I didn't try putting all original bulbs back in. Any reason why a LED in the left turn signal would impact the other lights there? Ground wire? Not sure.

Any advice and counseling would be appreciated. Why did I mess with that? My wife noted the dash lights were pretty dark so I had the big idea of fixing that.

 

in my '84 Series 3, the left turn signal has a different bulb socket than the Tachometer turn signal bulb socket.

It must be that the Tachometer came from a Series 2 and the Series 3 came with an updated electronic Speedometer ?? Therefore the hybrid wiring harness.

the left Turn Signal wiring has a Diode in-line in its wiring about 2 inches back from the left Speedometer bulb socket which I replaced.

My symptom is that the Left Turn Signal bulb indicator stops flashing after two or three flashes, but the Tachometer bulb does not do it.




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When weird electrical problems occur an easy place to begin the journey is by checking grounds, yes.

The metal part of the dashboard has two ground tabs for the instruments and lights. One is next to the speedo and the other next to the tach. Make sure the ground wires are still attached.

Also, the harness for the instruments is actually 2 or 3 sub-harnesses linked together. Make sure none of the connections came apart.

Cheers
DD

 

Thanks Doug -- very helpful. I was looking for the ground wires (briefly) and didn't see anything clearly. Are they just black wires attached to a screw?

Do you remember what they are coming off of? Is it a wire off the harness? Thanks so much for the assistance in this. Electrical issues like this scare me because the rabbit holes I've gone done have been deep and frustrating.