just purchased a '97 blazer ls and there are a couple small problems that need to be fixed:

1) the biggest issue: the shifter (auto) freely passes through all gears without pressing the button or brake.
2) the climate control is stuck on defrost.

before i start ripping things apart, does anyone have ideas or know of any common issues?


also, does anyone have a '97 fsm set that they'd be willing to part with?

 

The climate control is vacuum system. A leak in your vacuum system could be a possible cause, it could also be a stuck door or actuator.

 

one thing i really don't want to have to do is take the dash apart. hopefully it's just a vacuum problem.

any ideas about the shifter issue?

also, how do i calibrate the compass in the overhead console? the truck didn't come with an owner's manual.


edit:
before posting i tried driving in a tight circle three times to recalibrate the compass, but it's still wrong. do the instructions in this thread apply to the compass in the '97 overhead console?

 

Yup, those instructions should work for the compass.

On the climate control, as Hanr3 said, you probably have a vacuum hose that has a leak or has been disconnected. I would start in the engine compartment and make sure that the vacuum port to the fire wall is connected. From there, it's into the dash. I posted a schematic of the vacuum layout awhile back (CLICK HERE). You shouldn't need to pull the dash entirely apart, but you will have to pull off the lower hush panels.

On the shifter, it sounds like the button has either jammed down inside or the interlock has failed in the mechanism. This is a floor shifter correct...? If so, you should be able to pull off the console. Having never needed to pull mine apart, I don't know what to expect inside, but there should be a rod that comes down the inside of the main shifter lever that should have a catch on the end of it. It is possible that this rod or catch is hung up and just needs some lubrication and coaxing to get it to work again.

 

pictures: http://magtec.rvglug.org/misc/blazer/

the blower works fine, the blender door works. but the vents won't budge from defrost (and turning on the a/c doesn't seem to have any effect, but it is winter in wisconsin so it's a little hard to tell). i'll check the vacuum line at the firewall. at least the heater works.

yes, it's a floor shifter. when i press the button, i can hear a clicking sound that seems to come from the general area of the steering column. the shifter is free-range, though, and i don't want to accidently bump it into reverse at 70mph.

 

fixed the compass: the zone was set to 55.

 

Yup, that'll throw it off! LOL. Glad you got it fixed!

 

now that it's warming up i've had a chance to investigate...

re: free-range shifter:
the lock mechanism on the shifter snapped off. looks like i'd have to replace the shift lever to fix it.

re: climate control:
haven't diagnosed the problem yet, but i found evidence that someone else was inside the dash -
http://magtec.rvglug.org/misc/blazer/hvac.jpg

 

well, i think i found the problem (or at least part of the problem):
http://magtec.rvglug.org/misc/blazer/greyvac.jpg

and here's where the line is apparently supposed to connect to (thanks shadowhawk):
http://www.treasureboards.com/blazer/core14.html


edit:
fixed - reconnected the grey vacuum line, no more vacuum leak and now the vents switch like they are supposed to. i had to fully recline the passenger seat and lay on my back with my head underneath the dash to do it.

http://magtec.rvglug.org/misc/blazer/greyvac2.jpg