Climate control not working

[Skytrekin]

The climate control is not working. The fan comes on, but its stuck on defrost only. I replaced the controler with a new one and checked the fuses. 94 Lumina sedan 3.1
I have seen some lines under the passenger side panel, but havnet found anything broken. It doesnt switch to vent or heat or A/C.
Another problem is the reverse lights dont come on. I checked and replaced the rear bulbs with new, but no luck.
Also the cruise doesnt work, their isnt even a fuse place where it should go! no metal tabs to make contact under the hood!
Anyone have experience with this year please help! Thanks

[618stanley]

My son had a similar problem. The cruise didn't work, heater system was stuck on defrost, no vent, floor, etc. The vacuum system controls the two systems. Look for a small black vacuum line running from your cruise control, it runs towards the front of the car and down into an area behind the battery. There you will see a few vacuum lines running into a "T" of vacuum lines, it also runs into a cannister in front of the driver side tire. When i replaced the lines all worked perfectly. Do a search on this site on heater controls / cruise control and you'll find the info that will most likely fix your problem.

[Skytrekin]

Thanks soo much for that info.. I need a new battery anyway.. so that would be a good time to have a good look in that area.
Anyone have any experience with the reverse lights?

[Skytrekin]

Fixed it!!
After the blower motor giving up and stop working I had to change that as well. Them screws in the back of the convience center are small and kinda hard to get to, but once out you can get to the motor pretty easy.
Now the fix for the climate control was a broken vacuum line near the back of the center of the engine (where the vacuum comes from) I put a piece of rubber hose to splice the broken area and it works! Everything works!
Thanks so much for sharing your info.
Now to fix the reverse lights!

[Dan McCoy]

I've got a '93 Lumina with same problem....only defrost works. I thought it was the control unit in the dashboard so I replaced that but problem still exist. Then I found this post, can you be a bit more specific on where to look for possible vacuum leak.

[Dan McCoy]

I found the cracked plastic vacuum line, it was completely broken. It's the one going to the canister ball. I'm assuming I can get a replacement from a dealer or would the junk yard be just as good? 1993 Lumina.

[Skytrekin]

I would go with what ever is cheaper.. even rubber vacuum hose to fit over it for a cheap fix.

[richtazz]

There is an oval rubber block on the top of the throttle body with 3 or 4 plastic tubes coming off of it. THe HVAC gets it's vacuum from this block, as well as the MAP sensor, and fuel pressure regulator. Follow each of them ( although I beleive the second one in from the left is the one you're looking for) as the meander their way around the engine compartment until you find a split or burnt spot in it. 5/32" id vacuum hose fits it nice and snug, and will work as a permanent fix. IF it's burnt, make sure you isolate it from the source of heat (like tying it to something with a zip-tie) so it doesn't burn again.

[blitz9198]

for the reverse lights, have your neutral safety switch checked out, make sure your column shifter is aligned properly, and when in reverse jiggle the shifter without taking it out of gear....they should come on....i have the same problem, they tell me its in the column i just dont feel like taking it apart

[Skytrekin]

Thanks for your reply,
I havent tryed wiggling the shifter yet (column) but the pointer doesnt line up with the respective gear. I wonder how you adjust the pointer so drive is in "D"?

[richtazz]

I believe the adjustment is at the bracket where the cable attaches to the transmission. You place the car in drive (engine not running of course), then loosen the nut on the arm that is attached to the transmission, and reposition the arm while someone holds the shifter in position then retighten the nut. It may take a little trial and error to get it right.

[Carwhiz]

Reverse Lights: you may need to look on a wiring diagram and follow that through to determine where/what's broken. You can find wiring diagrams on autozone's website and they aren't too complicated to read. The h/vac unit and cruise control are all vacuum operated and it is common for the line to break underneath the battery. You can simply replace it with rubber vacuum line hose. There is a vacuum diagram on the emission label under the hood too, that's how i found my leak. This particular vacuum line begins at the pressure regulator(I believe), goes under the plennum, connects to the MAP, then goes to the cruise control servo, and then to the vacuum canister that is in your driver side fender. The vacuum cansiter helps even out vacuum pressure, which helps even out idling, so if you ever have small idling problems, check this vacuum line out first.

[KaiserM715]

I have read several of the other posts on the vacuum leak and the HVAC system. Many mention the vacuum reservoir (or vacuum ball) being behind a fender. Does this mean in between the metal outer fender and the inner fender in the engine bay? Is there a more specific location (in front of wheel, behind wheel, driver's side, etc.)? Thanks for the information in advance!!