Help, Im Melting In S.c.

[big worm]

last winter, i decided to replace my factory radio with one of those fancy sony cd/ mp3 players. installation was awful. ive installed some stereos before in a number of different trucks, but the lc is a real pain for a stereo switchout. everything seemed to go well. however, as i was riding around enjoying my new tunes, i realized that there was a noise now coming from the heater. it sounds like something is stuck in the fan. it still blows hot , but it is now noisy whereas before it was quiet.
well, now that summertime is here, my ac unit only blows hot air. has anyone had similar problems after a cd player install? my friend is a really good mechanic, and he tested freon compression and said it is good. he also looked up the ac wiring diagrams and traced all wires to the blower and fuses with a wire tester, and all was good. i also took apart the dash again, and everything "looks" good. has anyone ever had to replace the ac/heater control in the dashboard?
any info would be appreciated.

 

[gbell210]

What year rig is yours?
Mines a 94 and the install was fairly easy except unplugging all the dash switches (that was the only time consuming part) For 95-97 I think its even easier? But I got a Scoche (spelling?) harness from walmart and wired to the aftermarket stereo ... all went well except I had to disconnect the remote turn on wire(blue) for an aftermarket amp or a power antenna, because that would blow my dome/alarm fuse with the harness. Only thing I can think of.. maybe some wires for the AC/Heater controls aren't making a good connection??

Also.. does your compressor even activate.. do your RPMs increase when you press the A/C button?

 

[big worm]

i have a 93.
i dont know much about the ac, but my friend does, and he determined that the compressor is fine. the freon compression is good but when you hit the ac button nothing happens with the compressor.
he told me also that my fan could be making a weird noise because the ac/heat control head isnt putting off enough power. also, only half the lights work.

 

[flintknapper]

i have a 93.
i dont know much about the ac, but my friend does, and he determined that the compressor is fine. the freon compression is good but when you hit the ac button nothing happens with the compressor.
he told me also that my fan could be making a weird noise because the ac/heat control head isnt putting off enough power. also, only half the lights work.

You don't say how your friend checked the system, but to properly check the refrigeration charge he would need a set of gauges and the compressor would need to be working in order to see what the high side was doing.

Might want to make a visit to an automotive A/C shop for a diagnosis. The repair MIGHT be something you could do (depending upon what they find).

 

[big worm]

my friend did use guages, and now that you mention, i remember him saying that the compressor worked fine. he traced all wires except for behind the actual ac control itself. everything was fine according to the wire tester. has anyone ever had the ac/heat control head stop working? its just strange that it happened after install of a stereo, and that the blower works fine, just no cold air and a weird noise when blowing hard.

 

[Darwood]

my friend did use guages, and now that you mention, i remember him saying that the compressor worked fine. he traced all wires except for behind the actual ac control itself. everything was fine according to the wire tester. has anyone ever had the ac/heat control head stop working? its just strange that it happened after install of a stereo, and that the blower works fine, just no cold air and a weird noise when blowing hard.

This might sound too simple, but when you had the radio surround/dash off are you sure you pluged the AC controls back into the AC module. I'm assuming you unplugged it to get the surround off to get better access to the head unit. I think there are 2 or 3 plugs that go into the control module. Maybe one didn't get plugged in all the way?

 

[big worm]

im 99.999% sure, but im going to do surgery w/ a wire tester this weekend, so ill see. i took the dash back apart after the stereo install, and plugged it in w/ the dash apart, and still no cool air. i almost wish that i had taken it to circuit city. seems like everything i touch mechanically, i break it worse and something else breaks too. the ac/heat head unit seems so simple on the inside though, it doesnt seem to have a lot of room for error, other than an obviosly loose connection.

 

[flintknapper]

im 99.999% sure, but im going to do surgery w/ a wire tester this weekend, so ill see. i took the dash back apart after the stereo install, and plugged it in w/ the dash apart, and still no cool air. i almost wish that i had taken it to circuit city. seems like everything i touch mechanically, i break it worse and something else breaks too. the ac/heat head unit seems so simple on the inside though, it doesnt seem to have a lot of room for error, other than an obviosly loose connection.

Well, let us know what you find out. Also, be sure to check that the compressor either IS or ISN'T functioning. If it isn't then there could be several reasons why.

I don't have a FSM for a '93 model so I don't know if your units A/C control has a position sensor similar to my '97 or not. Be sure that all connections are tight and in their proper place.

IF your compressor is working properly AND the system is fully charged....then you may have a problem at the air mixer. Check to see that ALL vent positions flow air from the blower and post back your findings.