I have a 1987 xj6 seriesIII and It's American car and the trip computer works fine when your driving but as soon as you turn off the key everything resets to 0 is there a reason why this happens? I am thankful in advance for everyone here thanks

 

Dunno if this applies to your vintage, but in the late models like my 2011 XF, there are three trip computers: A, B, and Auto. A and B can be reset whenever you like, and Auto always resets when you start the car (or shut off, who can tell?). Maybe you have this option, too?

 

How do you set the A and B or auto I really appreciate your help

 

I'm sure this won't help you, 'cause touch screens were Sci-Fi back in 1987. But since you asked... On an XF, you go to the Vehicle page of the infotainment screen, and there you can choose A, B or Auto. Then the display between the gauges shows the trip guage of your choosing and the button on the end of the turn signal stalk toggles Avg. mpg, distance, range, etc.

 

guitarranger11, you ought to ask this in the forum for your model year...
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