Well I don't quite have the problems that some seem to have had with their indicators/hazard lights, but I have a weird little issue that has been giving me a headache for a few days, and would appreciate any advice!

The indicators work as they should, front and back, flashing away happily. The hazards work as they should, front and back, left and right, flashing away happily.

What doesn't work as they should are my dash lights. My hazard warning light works just fine, flashing in time with the exterior lights, but the left and right turn signal lights flash off-time with the exterior lights, and only illuminate very briefly. With hazards off, if I apply a left or right turn signal, the corresponding dash light will light up for a fraction of a second, and then stay off even with the external lights working.

OK, confession time here, and some may have already guessed this (since the dash lights are only illuminating for a brief period of time), but I have installed dash LEDs in place of the globes. Complicating this further is that my left and right turn signal dash lights never used to work, and the bulbs appeared to be fine when I replaced them.

So what could be going on here to cause all this weirdness? At first I thought that perhaps the left and right LEDs were installed incorrectly, but swapping polarity meant that they didn't illuminate at all. Are those diodes for the left and right warning lamps susceptible to failure that might cause this? Do I even need them once I have installed LEDs in place of the bulbs? Has anyone else come across something like this?!

Thanks in advance,

Dave

 

The ground for the dash would appear to be the culprit here, given that the dash turn signals were NOT working before the change to LEDs. ???

 

Yeah that just means excessive resistance going to the dash lights. So either the ground for the cluster, which is common, or part of the silly circuit panel is dirty. I've take the cluster out, clean all the points, clean the harness points and maybe add an extra ground wire.

 

When I changed all my instrument cluster lights to LED's, I also replaced the circuit board. You can go to Jaguar classic parts and find which circuit board will work for you XJS. Mine is a 93, so yours will be different. These circuit boards are still available. Changing the board just eliminated any glitches.

 

Following on from this, do you know if changing the instrument turn signals to LEDs (for a brighter light) will affect the flash rate for the turn signals ?
I have read that changing the front or rear bulbs to LEDs can or will cause the turn signals to flash too quickly, so I wonder if changing the instrument bulbs will do the same thing.
Info gratefully received..
Tx.

 

I would think adding LEDs would cause the light to flash slower as there is less current to trigger the flash module. Just like when a bulb is out the signal lights flash slow. Increased current causes light to flash quickly.
LEDs are slower to respond with light than regular bulbs.

 

Oddly, my information is to the contrary:- LEDs draw less current, and therefore the turn signals (front, rear, and dash) flash more quickly. But being small bulbs/LEDs, I wondered if the dash lights would affect the current draw to the same extent as changing front or rear bulbs.