a/c control levers

[19mike69]

can someone tell me how hard it is to replace one of the slide levers on the a/c -heater controls?....the top one on mine(defr i think)is broke in half and ive noticed they sell replacement levers and wondered how hard the are to swap out.....also one more question.....my fan only seems to want to work on off and med....it looks like a new switch too....i do know if you put it on low or on high that little resistor in the blower housing gets red hot,does that mean ITS bad or the switch is messed up making the res to get hot?....thanks alot

[JimKshortstep4x4]

Check your relay on your heater box. It controls the high speed.

The resisters will get hot when the fan motor is running.

Replacing the lever is not too bad of a job. Getting the knobs off can be tricky. I usually take needle nose and spread it so that I lightly grip the lever and then tap the needle nose against the knob.


Jim

[Hutch]

Check the ground wire that is located on the high speed fan relay located on the outside of the heater boxit is inside the cab close to the passenger fender. It is behind the glovebox
There should be a ground from the relay to the inside firewall.
On mine the wire had broken.

The symtoms were:

Switch Low=low speed
Switch Med=med speed
Switch high =low speed

Put the switch on high and run a temporary ground to the relay to test.

I have never replaced the upper lever but have been told that the kit comes with everything and it is not that hard to replace.
I have noticed that some of the vendors offer a replacement lever which is made of steel versus the lightweight original.

Yes the resistor should get hot.

Have fun

[Andy4639]

I have fixed levers a couple timess on different controlers. I just used some small screws and cut some alimnium to join the two peices back together again.I have had the one in my truck now for about 10 years and it's not broken again. I have two more that I have done this to and they are still waiting to be used. As far as the resister I don't have a clue, sorry.


It might be the wiring plug behind the switch, mine started melting and loosing ground and not working, replaced the connector with all new spade connectors and everything has work fine since.

[19mike69]

Hutch....the resistor im talking about is something different than the relay you are talking about right?...ill have to look tomorrow but i think i know where you are talking about...is it pretty small?....and you say there should be a ground wire coming off of it to the firewall?

[Suicide-D]

it is easy... I did the rebuild on mine in about 30 minutes... I ordered the kit from Chevy Duty...replaced all 3 levers... kit was 20.00 bucks for the black knobs and it comes with a new face sticker... I didn't use .... the chrome kit was a little more. but the levers are metal and seem pretty solid.

[68gmcjon]

Do you guys know where i could get one of those resistors that contro; the speed?

[PICKMUP]

The AC repair kit has one arm...and it is a lot harder to replace than the non AC arms. The manufacturer says to epoxy it back together, after you drill it apart. I don't think so! You need to be using some taps & screws...very carefully. It is a steel arm, not pot metal, so it should last. It does not fit, feel & work as well as the original, but it is the only option I know of.

[Blue Beard]

I believe it was GMC Pauls that has unbreakable levers.

Haven't seen these, don't know the quality.

But from what I've seen posted he reliable.

Blue Beard

[Hutch]

Yes the resistor is inside the heater box (i think)
Relay is near the passenger side fender inside the cab between the heater box and inside cowl vents at the top.
It has a harness attached and is attached to the inside heater box.

68gmcjon
Try some of the boardvendors located on the main page.
http://67-72chevytrucks.com

[72'BBGMCSGCC]

GMC Paul told me about the high speed relay and was very helpful, but I found out the the problem was the high speed relay wasn't grounded. You might want to check. good luck.

[19mike69]

i checked the relay and its grounded,or appears to be.....what mine does is it barley,barley works on low,seems to work ok on med,and wont do anything on high.....could it be the switch itself?....i looked at GMC Pauls site and found a rebuilt A/C control assembly for like $114.....if i need the new switch and my top lever is broke,dont you think it would be better,and easier to just buy the rebuilt control assembly?....and i guess buy 3 new cables since the one on the lever that is broke wont move.....does anybody have any ideas why my fan wont blow the right speeds?....i looked at the relay and it seems to be ok,i guess you can check it somehow i just dont know how

[Hutch]

Some of the a/c controls don't come with the switch, check the connector to the back of switch for burned terminals.
Run a tempoirary ground (short piece of wire)from the Relay base to any frame ground while the heater switch is on high for a test.

Depends on the $.s you have

If it was me I would fix the broken lever and troubleshoot the fan issue.

[19mike69]

Hutch....ok,ill try and run a jumper wire tomorrow and see what happens....i do know that on the back of the fan switch there is that black plug that the wires go into....well,mine is sort of melted or something....maybe there is something wrong inside of that....but ill try the jumper wire first and see what happens....thanks alot

[Andy4639]

It might be the wiring plug behind the switch, mine started melting and loosing ground and not working, replaced the connector with all new spade connectors and everything has work fine ever since.

[72'BBGMCSGCC]

Mine didn't work on high either,I tried a jumper wire and found out it wasn't grounded.Try this first and then buy another high relay switch and try the new switch. They are not very expensive. Good luck.

[19mike69]

well,tried a jumper wire today and it still does the same thing....so now what do i do?.....i dont suppose it could be the fan itself could it?...i figure either the fan will work or it wont,not in between.....if its the switch or the plug behind it,wheres the best place to get these?....or could it be the high speed relay?....hell,i dont know

[Hutch]

you might want to take the plug off of the back of the switch and try jumpering between the different connectors.
I am not sure what each wire is but the switch just makes a connection between the contacts, one of them may be a ground wire or it may get the ground through the mount.
You might blow a fuse so have some handy.
Start with the switch and work back from there.