In my xj6 series 3 the odometer never worked since I bought the car. The speedometer was working until one day it quit. What it does is that it works when I accelerate but when I let go of the gas it bounces. I notice if I give a slight bang on the speedometer the needle moves around a little bit. What should be my first step? Also the sunroof does not work anyone know how to check that out? Finally, when I activate the cruise control it just accelerates really fast and doesn't stop until I turn off the cruise control. Thanks! Also, middle heat vent doesn't work but left and right side do?

 

Electric speedo or cable drive speedo? 1982-83 was the change period. If electric, the transducer on the side of the transmission is the likely culprit.

If cable drive, try lubricating the cables




First, do all the power windows work? The sunroof is on the same circuit...so if the windows work then you at least know the relay and breakers are OK.




There's a good write-up on cruise control faults. I'll try to find it for you



Might be normal depending on the settings and temps. The center vents open only when MAX cooling is called for. For 'blend' or 'heat', it stays closed.


Cheers
DD

 

Thanks for the reply, all the windows in the car do work just not the sunroof.

 

Here's some cruise control info

Cruise Control


Cheers
DD

 

OK, so the upstream circuit is OK. Good!

Do you have a test light to check for voltage at the switch and/or voltage at the motor?

Or, another approach----remove the switch and carefully pry it open to clean the contacts. There's at least a 50-50 chance that'll fix the problem!

Cheers
DD