The haeter a/c fan moter only works on high.

The main reason for a resistor to go bad is because the blower is pulling too many amps to work. Check your blower motor.

The heater resistor has probably gone out. It should be located in the blower housing.

You have a relay there are 2 speeds low speed and high speed this is controled by a cooling fan module if you changed fan and it does not work then you will need to check the fan module, first the relay its in the engine fuse junction box High speed is marked on the relay C1056 and low marked C1058, here is what you can do go to the high spped relay open thhe cover and expose the relay with key on collapse the relay does the fan come on? if it doesnt replace the fan module if it does you will still have to replace the fan module here is the location is at the radiator on the front (may be under shroud)

Hi anubus33
If the blower moter is working on low speed only and it's not making any strange noises,there are 3
components that can cause this problem. First and the most common is the blower moter resistor,
located under the hood at the center of the firewall, next is the high blower relay(not uncommon)
located in the junction box between the right strut tower and the firewall and the fan switch on the
dash. An easy way out is to stop by the local salvage yard and p.u. a resistor+relay for cheap they
should be the same as many other GM'S of the same year. The counter guy at the yard will know.
Hope this helps.

the fan relay is activated from the ECM which gets the message from the coolant temperature sensor to switch the fans on ( more than likely the problem)
they should be running at 85 c or well before 212 F so check fuses (2) for failure and check for power to the relay as well to check if the fans are spinning freely
the fan relay will have an emblem on the cover and be situated next to the battery in the big block of relays

Hello leebarker
The blower moter switch or the blower moter controler can cause this
problem. Remove the plug from the switch, use a 12v test light to locate
the 12v power wire in the plug. Next with a small jumper wire bring power from the 12v contact to the low and medium speed contacts on
the plug if the blower changes speed replace the switch if it still only
has high replace the controler. The blower controler is located on the
passenger side end of the heat-a/c box near the blower moter.
By the way the key must be in the on position for this test.
I hope this helps. Good luck.

the high blower relay controls the high blower only
you need a new blower motor switch you control on the dash

First lets deal with front blower. If all fuses checked, there should be a resistor block (which when it goes usually leaves you with high fan only) for fan located on firewall, under the hood on passenger side behind the front strut mount area. It measures 1-1/2" x 3" approx, and will have a wire connector on it. It usually pulls out, with a bit of a fight. Disconnect your battery neg(-) just to be safe before you do. Replace it, that should cure front blower problem. (about $20 at autoparts store) Ask them for "blower motor resistor pack) very common item so they should know what your talking about.

it could be the wire behind the fuse panel itself or the plug that plugs into the fan check these with a 12 volt tester and you should be able to find the problem also check the fuses under the hood and if you have an owners manual check in there and see if any are listed and where they are located