New to the forum, looks like a lot of good information here. I looked for the answer to my question, but could not find the same situation that I have.

The wife's expy is having a/c issues. The blower will only blow on high. The low, med/low and medium speeds will not work on the control panel in the dash. I have replaced the blower relay and the actual blower speed switch in the dash. Neither of these parts made any positive difference. Tonight she said that the low speed will work in the normal a/c mode, but not in the max a/c mode. I took a ride to see for myself and she was correct. The faster you go, the faster the low speed works. When you stop, the air stops as well. Anybody have any other tips for me to try before I take it to a mechanic? BASSHAWK

 

Did you check the heater/blower motor resistor? The resistor has a thermal limiter that can go open and cause the blower to only have HI function..

 

I havenot checked the resistor. How do I go about checking this? Should I just replace it to check it or is there a way to check it without replacing it? BASSHAWK

 

The heater resister is in the heater case/plenum.. It has what looks like a 'diode' across the resistor coils.. With it removed from the case, and the wires/connector still atached, 'jump' across the thermal limiter connection/s and the low speeds will/should work if it's a resistor issue..

Here's a general pic of what the resistor looks like and location.... #8 in the diagram...



[IMG]local://upfiles/6756/E3AAAA6AEBC84D91AB9CA13941C29729.gif[/IMG]

 

Thanks for the info Hayapower. I'll give this a try tomorrow and reply back with my findings. BASSHAWK

 

Here's a bit more clear view of what a heater resistor looks like when removed.. You can see the thermal limiter.. If it proves out to be failed, it will need to be replaced...

[IMG]local://upfiles/6756/DB772B4E8D1B48EC9F93B61C8F92D07E.gif[/IMG]

 

Hayapower, I looked inside the glove box of the wife's expy and it looks like I will need to take the glove box and its mounting bracket out in order to get to the resistor. Is this a correct assumption? How far back behind the bracket will the resistor be? BASSHAWK

 

The heater resister is mounted next to the blower motor.. The blower hangs downwards on the plenum.. You can release/move the glove door stop 'tabs' to clear the opening for access, as well as from the R/H lower instrument panel..

[IMG]local://upfiles/6756/6F23450D7F5741A6A924C52B594E7C48.gif[/IMG]

[IMG]local://upfiles/6756/555A7A5761DA46DAAFCA889A27A9BD6A.gif[/IMG]

 

Hayapower, I found the heater resistor with the aid of your schematics. Thanks for the pics. I jumped the coils with a shaft and the blower would blow high regardless of what speed I had the speed set at on the dash. It did not matter whether I had it blowing through the vents or through the defrost vents, it always blew out of the bottom foot warmer vents when jumped. Is this what I was looking for? I tried to get one at Autozone, but it was not available. I figured what the heck, I got the cover off I may as well replace it while I have access to it. Do you think this might be my problem based on what I described? BASSHAWK

 

You should only jump across the thermal limiter, like if it were a blown fuse.. The fan demand selections 'should' then be same as a good working system.. If you continually select different vent/defrost options without starting the engine, you'll deplete the available vacuum in the reservoir and the vent/s and vacuum control motors won't operate as commanded..