I know the subject line seems weird right? When I do the key-to-on position while holding down the odometer button my '01 XJ Limited 4.0L goes through all the onboard diags and finishes with no error codes, however the little motor shaped amber LED does *not* light up during this diag test. Is this normal or is it something I should be concerned about? My XJ runs okay, it idles a little rough but it has always done that since I got it with 97K on the ODO. It has 160K on it now and runs exactly the same as it did when I first turned it over and drove it.

 

Bulb is probably burned out. It's a regular 74 bulb in the 97-01 Cherokee. The only indicator light that's actually an LED is the low fuel light.

 

I had the same problem in my 2001 wj, I did the key on three times trick and it showed codes but no light! The bulb was bad; after I changed it out, it stayed lit.