Dashboard reostat light control has stopped working. Was intermittent when revolving the knob underneath the steering column. Would lighten the dashboard light bulb when on high illumination but now nothing. The bulb has not failed.

Before attempting to get at the reostat what is the proper way . I note the reostat is fastened permanently to the vinyl like cover, so removing the covering is the only way to get my meter on it to test. Hope this makes sense but other XJ-S owners of my vintage may have had the same problem. Then of course comes the problem to what do to replace (if it is the fault) the reostat. Is this item still available.

Is there a safe quick access to removal of the vinyl covering. I don’t want to start removing what is not necessary. It is close to the fuse cluster. I’m a bit stumped on this one.

cheers and thanks.
Mike

 

My previous note. I must have been in brain fade. The rheostat was easy to locate. But before I attempt to do so I would appreciate some advise as to how to get the knob off the shaft so I can remove the rheostat itself. If it simply pulls offs I’ll use a bit of force but I don’t want to do the dumb thing and break it.

thanks

mike

 

Memory, hahaha.

The knob pulls off, but its been 30 years since I ventured there on any XJS or Series 2 car.

Mine all went hissy, I dropped that under dash panel, 3 screws I think, sprayed some WD40 type spray, into the unit. DO NOT drown it, just a sniff of a spray, work that sucker, then refitted that trim panel.. All sorted except one, which I simply joined the wires and called it fixed.

 

there should be a grubscrew holding the knob in place. its deep in the vinyl so you cant see it so be careful as i wasnt so i yanked the guts of the rheostat out with the knob. it was pretty easy to reassemble though.. hope this helps

 

Thanks Leo.

Maybe I need another XJS, just for practice????????

HAHAHAHA, like a whole in the bloody head.

 

maybe there are different ones for whatever year. i couldnt see any other way than yanking the thing off but when the guts of the stat came out like a fishes intestines i just uttered some profanities and undid the grubscrew and uttered some more

 

Thanks Grant and others for your advice.

Rheostat came off easily after a little squirt with CRC. It’s stuffed inside. I’m no auto electric techo but I’m told I can just join the 3 wires and my dashboard light will work but bright. Ok with me but I would have thought that one of the wires would be an earth. On checking with Dr Google again it is said just join the 3 spades together.

would appreciate you XJ-S experts advice here again.

with thanks

mike

 

Now your asking.

I reckon I did join the 3 wires, but that was 30+ years ago, and a lot of beer has flowed since then.

I simply do not remember leaving a spare wire hanging, that is not my normal style.

 

Just trial and error it, nothing fuses. I did this and it made a HUGE difference to the brightness. I seem to recall you can effectively join the three using the male connectors already on the rheostat, juts a matter of moving one or two of the wires to a double connector.

 

Success. Thank you guys for your advice. I now have dashboard lights without a Rheostat. I combined the wires back to the old rheostat by unscrewing one of left terminal male spades placed it on the right giving me 3 spades to put the 3 wires (female spades) together. Bingo it worked. As mentioned by others the original bulbs on the instrument panels are not that bright so I may now consider LEDs but whatever what’s there works.

thanks again

mike

 

The easiest dash light upgrade is to use 5 watt push fits in place of the OEM 2 watts. Also, the bulbs have green filters in front of them. If you remove these as well (you need to separate the white from the black part of the instrument pod to do this - not difficult, do it on a sheet on the dining room table) the illumination gets FAR better. Highly recommended.

 

Assuming your car is left hand drive, on the left side just under the dash pad next to the bonnet release is a plastic slotted screw that is a 1/4 turn release connector that allows the pad to be lowered (it is on hinges and swings down). If R/H drive, look at the r/h side next to the bonnet release for the 1/4 turn screw.

With the knee pad lowered you can then get access to the back of the reostat. Knob has a small hole on the stem that you push a small pin ( I use a finish nail) in to depress the knob release and while it is depressed, pull the knob off. You can then remove the nut that secures the rheostat, then reach up under the dash and drop the rheostat down. If I remember correctly, you can spray electrical contact cleaner on the coiled wire and the wipe arm to improve contact.

Good luck.