C68 question

[Toyvet1]

According to GM service bullentin states 1990 and 1991 C68 climate control programers are not interchangable. The parts book show 90/91 and LT5/L98 programers. What is the differance between the four programers? And why are 90/91 not interchangable?

Are you talking about the box that is just above the gas pedal, or the dash ac controller?

[Toyvet1]

I am talking about the programer located under the dash above gas pedal.

I know you can use the corresponding year L98 box. Not sure what the difference would be between the 90 and the 91. It would be worthwhile just to try the swap and see.

[Toyvet1]

Can I take that as a offer that you are going to send me two programers for the exparement..

I was thinkling the L98 box would work.Guess Ill find one of those to work with.

[-=Jeff=-]

Originally Posted by Toyvet1

Can I take that as a offer that you are going to send me two programers for the exparement..

I was thinkling the L98 box would work.Guess Ill find one of those to work with.

I take it mine did not work?

[Toyvet1]

-=jeff=- changing them made no difference. Sometime it will work and sometime not. When I put it all back together it was working. So Ive changed outside temp sensor, dash unit and the programer. Ground is good and power lead does have any sign of ground. Im at a loss...maybe find a new 1990 L98 programer?

[-=Jeff=-]

so what parts are still changed? Sensor and programmer? yeah that would be the next step get a new programmer

[Toyvet1]

Sensor is new. Everything else is orignal.