Instrument Panel Bulbs

[peterjohn77]

Sirs

The illumination on my instrument panel on my 78 XJS is rather gloomy. The manual suggests that the bulbs are 2.2W. Can higher watt bulbs be used?

Thanks

Peter

[poprivet]

Apart from a blown bulb, the main reason for poor illumination from the five bulbs in the pod are the green plastic shades which give the diffused effect. The plastic goes very dark, almost black with time. I'm not aware of them being available new but there are a couple of easy fixes, either remove the shades and coat the bulb with a suitable tinted lacquer to give the right colour or using a hot sharp object melt 4 or 5 tiny holes in the shade to allow more light through. The last option is what i did and although you loose some of the green colour you do gain better lighting.
While the pod is apart, it's worth the effort to paint the dark plastic areas behind the dials with white paint which will also brighten things up a bit. Make sure all connections, especially the earth's are sound, check all the tiny warning bulbs and replace any that are blackened or blown.
Lastly, its also worth by-passing the dimmer switch as the contacts can lose voltage and most owners have it turned up to maximum all the time anyway.
Higher wattage bulbs may cause problems with heat on the plastic and shouldn't really be necessary.
Pop

[almcl]

Not entirely sure about a 78 XJS but both my 78 and 84 XJ6s and 84 XJ12 could (and did) have a higher wattage bulb fitted to the speedo only.

I forget the figures and the bulb fitting but it was of the order of 2.2 watts became 3. There was no problem with heat and the light was noticeably better. The XJ was too dim for many right from the factory and several have reported good results from removing the rheostat from the circuit.

Not sure if this applies to an XJS, my 93 is a lot brighter than any XJ I have ever seen.

[peterjohn77]

Thansk for your help!!