transaero

iTrader: (6)

Hey guys, I'm trying to figure out why my heat and air are not working. Turning the switches on in the cabin does nothing. No air, hot or cold, come out of the vents. Is this mean I have a blown blower motor and I need to replace it?


Thanks,

Rob

Ingram78

Probly or fuse!

mmadden55

x3

transaero

iTrader: (6)

No, I've already changed all the blown fuzes. It must be the blower than.

Is there anyway to check the freon level without taking it to a shop?

Ingram78

If the blower isn't working, it's the blower.
If you turn the ac on and the clutch on the compressor under the hood doesn't engage or it cycles (clutch) frequently it's low on freon or has a leak.

transaero

iTrader: (6)

This may sound stupid, but the clutch would be the wheel connected to the belt system to the right in the engine bay right?

Sorry, I'm only 17, but I gotta learn somehow, right?

KaI_S

If the blower is not working after you check the fuse, try to power or ground test on the blower motor.... it might cut wire or bad ground...etc

Ingram78

The ac compressor is ran off a belt and pulley, should be on the top passenger side of engine . It free wheels if ac is not on and some newer models it engage when the windshield defroster is on. It should engage and you should be able to hear it when you turn the ac on. When it is engaged the front part of the compressor should be spinning with the engine.

But I believe the problem is your blower motor do as suggested above and put 12volts and a good ground to the motor and if it doesn't run you have a bad blower.

sofakingdom

iTrader: (1)

Yup, could be the blower motor. Easy enough to test for that: unplug the purple wire from it, connect a piece of about #12 wire (house wire is fine) between the motor terminal and the batt. If the motor runs, it's fine. Replace it if necessary, otherwise plug the purple wire back in and continue.

A very common cause of total system failure in GM cars of this age is the main 12V supply to the entire system. Remove the AC control head from the dash and inspect its wiring. You will see a switch with about 5 wires that controls fan speed, and another switch with a green (AC clutch), another color I forget what (goes to the fan switch), and brown (12V feed). The brown wire runs up into the dash and connects to a wire that comes from a different harness, maybe 12" or so up into there. When you find that connector, observe that it is of the absolutely STUPIDEST POSSIBLE design (uses the plastic to maintain contact tension), absolutely 100% ironclad take-it-to-the bank GUARANTEED TO FAIL; and that it is BURNT TO ASHES. Cut both ends of it off and replace with the BIG THICK HEAVY-DUTY yellow slide terminals; not the little weenie ones that are just like the blue and red ones, you want the BIC THICK HEAVY-DUTY ones. Insulated if possible. If you can't get the insulated ones, get some HEAVY-DUTY sleeving you can slide over them and tape it in place.

Then once you've done that, go back out under the hood and follow the purple wire referenced above, leading away from the blower motor. In a few inches you will come to a small box, aka high-speed relay, whose plug has that purple wire, a couple of smaller ones, and a BIG FAT red one. The purpose of that wire is to bring 12V to the relay, allowing the very high current of the fan motor when in high speed, to follow a more direct path than through the switch in the dash. Follow that red one over toward the driver's side. About above the pass side valve cover, you will come to another one of that exact same type of connector, which will also be burnt to ash. Replace it the same way.

transaero

iTrader: (6)

Hey guys, with summer here I figured I would tackle this again. Kinda gave up before since winter had come around.

I have done most of the things suggested: no fuses are burnt, the wires that sofakingdom suggested I find and replace were still intact, and the blower runs when connected directly to the battery. I also replaced the two blower relays (high speed relay looked good). There are two because I have a digital dashboard, so there are some extra doohickeys.

So, I'm pretty sure the main problem is the blower motor s not getting power, so what would my next thing to check out?


Also, as for the connectors, I found the red wired one in in it's proper location, but the second one attached to the brown wire was located in the engine bay along the firewall. Is this normal for digital dash cars?

antares57

iTrader: (8)

If everything else seems to be working then it may be the actual fan switch which is directly behind the plate attached to the ****. I've had to replace mine in the past with a used one from Pick-N-Pull. Good luck.

transaero

iTrader: (6)

If you are talking about the hvac controls themselves, there are no ***** on the digital dahs controls, they are push button. This is what they look like:

antares57

iTrader: (8)

Is there a mechanical switch behind the "lo" and "hi" buttons?

transaero

iTrader: (6)

not sure. There is a connector with 4 or 5 wires coming from it though.

sofakingdom

iTrader: (1)

So, what did those 2 connectors look like inside when you unplugged them and looked down in them?

Look at the CONNECTORS, not the WIRES. Especially the one under the dash.

transaero

iTrader: (6)

Yes, the connector's looked good. A little bit of dirt in them but I cleaned them up.

I looked at some older threads for reference on what they looked like. I can take some pics if you want.