My 94 XJS runs perfect and passed the smog emmissions with flying colors but the “Check Engine” light on the dash does not come on. So it failed the test.
Any suggestions?
Dumb question: Have you checked the bulb?
You will need to pull the cluster.
My recommendation would be to disconnect the battery and disarm the air bag.
The airbag is not electrical it is inertial.
I no longer have the tool to disarm the airbag.
Find a tiny vice-grip pliers but you should not grip the disarm pin too hard.
Loosen the pin until it stops then you can loosen the bolts holding the bag.
It has been a while. Not sure if you need to drop the steering column.
As I recall, there are two plastic hidden in the upper corners.
Underneath there should be one Philips screws on each corner.
You will then be able to pull the cluster out and see the tiny bayonet bulbs.
I may have a few of them I’m not ever going to use.
Thank you. Wish me luck. I’m going in.
Geez, they even check the c.e. in Canada? Sounds like inspections are as strict there as they are in the U.K… 
Glad we’re not quite so fussy here in the States. 
Well it all depends on where you live in the USA. CA is pretty fussy. All cars 1976 and newer, and older tHan six years require a smog test in CA every two years. In addition to the emissions test there is a visual inspection which has been getting more comprehensive. A visual inspection of the catalytic converters is now required to verify that they are either OEM or California Air Resouces Board (CARB) approved.
Paul