my service engine soon light on my 1995 gmc jimmy won't turn on, and i cannot

[Steve]

test for codes...says link error? when you turn the key on before startup, the service engine soon light should come on, but it doesn't, and when i hook an OBD II tester up, i get a linking error message, so cannot check for faults...how do i fix that

 

[epiphaknee]

SES Light: Most likely the bubl has burned out in the instrument cluster for the SES light. To correct this you need to remove the instrument cluster and replace the bulb. This repair takes a little time but is not that difficult.

Link Error: Have you received this message before? I also receive this message on a regular basis on my 95. If I use a Snap On scanner everything works fine, however, if I use an Actron scanner I have to tip the Actron connector up to make contact and read the codes. It's a pain but it solves the problem.