Check the fluid level in the master cylinder.  It might be low and
your shift makes it slosh around and activate the light.  I think the
same light is often used for both low fluid warning as well as parking
brake.  But I could be wrong.

It sounds like you are talking about the 'brake failure' warning light.
 This means the brakes have failed and the vehicle is not safe to drive
until you find out 'why' the brakes have failed.

If you get stopped by the police for any reason and they see this light
on, you will be on the back end of a tow truck likely with an expensive
ticket to boot.  (been there, he would not believe for one second it was
a failure in th park brake cable causing the light to go on.)

The fluid check is the first step to see if one side hasn't got a leak
and emptied out.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
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