HVAC Head repair
Join Date: Jul 2009
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HVAC Head repair
Finally got tired of flocking with the HVAC head not turning on the fan (banging/fiddling head and trim panel at the head unit) and removed it to check internal pins connecting the two circuit boards. Removal was super easy with the radio tools, and the 2 trim face screws (in the radio opening) came out easily as well. Popping out the head, I brought it in to the house and separated the 8 or so plastic clips around the perimeter. Didn't see that clip at the rear that holds the one circuit board, so it separated the two boards right off. After getting out the board, I did see a little corrosion on all the pins. Used penetrating fluid, and soaked up the excess. Trimmed the plastic where the board hits (right side where the face printed circuit board hits the bottom rear circuit board) so it slides in a little more into that multi-pinned connector. Re-assembly was easy, and went back to the car to install it. For some reason, lining up those blasted two pins was a BEAR. Had that head out once before, did not remember having so much trouble fitting them into the two connections at the firewall. So, the big test? Assembled everything back into place, and cranked the car up. Turned on the fan, 100% works from start through all the speeds. Checked all air selection locations (floor, dash, mixtures) and they all worked great. A/C comes right on, and 'rest' function works as well. So, looks like I should get another 30K out of it but if not, simple to remove and do again! Seems no more banging that head/trim panel to get the fan to come on. 
Thought there was a second tutorial for this HVAC head repair but couldn't find it in my doc collection... .
Senior Member
Re: HVAC Head repair
Finally got tired of flocking with the HVAC head not turning on the fan (banging/fiddling head and trim panel at the head unit) and removed it to check internal pins connecting the two circuit boards. Removal was super easy with the radio tools, and the 2 trim face screws (in the radio opening) came out easily as well. Popping out the head, I brought it in to the house and separated the 8 or so plastic clips around the perimeter. Didn't see that clip at the rear that holds the one circuit board, so it separated the two boards right off. After getting out the board, I did see a little corrosion on all the pins. Used penetrating fluid, and soaked up the excess. Trimmed the plastic where the board hits (right side where the face printed circuit board hits the bottom rear circuit board) so it slides in a little more into that multi-pinned connector. Re-assembly was easy, and went back to the car to install it. For some reason, lining up those blasted two pins was a BEAR. Had that head out once before, did not remember having so much trouble fitting them into the two connections at the firewall. So, the big test? Assembled everything back into place, and cranked the car up. Turned on the fan, 100% works from start through all the speeds. Checked all air selection locations (floor, dash, mixtures) and they all worked great. A/C comes right on, and 'rest' function works as well. So, looks like I should get another 30K out of it but if not, simple to remove and do again! Seems no more banging that head/trim panel to get the fan to come on. Thought there was a second tutorial for this HVAC head repair but couldn't find it in my doc collection... .
I took mine apart last year and as I have the radio and bezel out now I thought I would look at that area again. I never did any mods last year as I thought the connection was fine, maybe I should do the mod.
Senior Member
Re: HVAC Head repair
Finally got tired of flocking with the HVAC head not turning on the fan (banging/fiddling head and trim panel at the head unit) and removed it to check internal pins connecting the two circuit boards. Removal was super easy with the radio tools, and the 2 trim face screws (in the radio opening) came out easily as well. Popping out the head, I brought it in to the house and separated the 8 or so plastic clips around the perimeter. Didn't see that clip at the rear that holds the one circuit board, so it separated the two boards right off. After getting out the board, I did see a little corrosion on all the pins. Used penetrating fluid, and soaked up the excess. Trimmed the plastic where the board hits (right side where the face printed circuit board hits the bottom rear circuit board) so it slides in a little more into that multi-pinned connector. Re-assembly was easy, and went back to the car to install it. For some reason, lining up those blasted two pins was a BEAR. Had that head out once before, did not remember having so much trouble fitting them into the two connections at the firewall. So, the big test? Assembled everything back into place, and cranked the car up. Turned on the fan, 100% works from start through all the speeds. Checked all air selection locations (floor, dash, mixtures) and they all worked great. A/C comes right on, and 'rest' function works as well. So, looks like I should get another 30K out of it but if not, simple to remove and do again! Seems no more banging that head/trim panel to get the fan to come on. Thought there was a second tutorial for this HVAC head repair but couldn't find it in my doc collection... .
and this one. CLICK
Join Date: Jul 2009
Location: Central South Carolina
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Re: HVAC Head repair
Yeah Dave, the first one is the one I used. On that tutorial, it says to 'record customer defined presets'? I didn't lose any radio settings and it was out of the car for quite a while. Anyway, it's still working fine, two trips so far. Am going shopping soon so that will be three trips. .
Last edited by onehundred80; 04-18-2019 at 04:17 PM.
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Re: HVAC Head repair
Finally got tired of flocking with the HVAC head not turning on the fan (banging/fiddling head and trim panel at the head unit) and removed it to check internal pins connecting the two circuit boards. Removal was super easy with the radio tools, and the 2 trim face screws (in the radio opening) came out easily as well. Popping out the head, I brought it in to the house and separated the 8 or so plastic clips around the perimeter. Didn't see that clip at the rear that holds the one circuit board, so it separated the two boards right off. After getting out the board, I did see a little corrosion on all the pins. Used penetrating fluid, and soaked up the excess. Trimmed the plastic where the board hits (right side where the face printed circuit board hits the bottom rear circuit board) so it slides in a little more into that multi-pinned connector. Re-assembly was easy, and went back to the car to install it. For some reason, lining up those blasted two pins was a BEAR. Had that head out once before, did not remember having so much trouble fitting them into the two connections at the firewall. So, the big test? Assembled everything back into place, and cranked the car up. Turned on the fan, 100% works from start through all the speeds. Checked all air selection locations (floor, dash, mixtures) and they all worked great. A/C comes right on, and 'rest' function works as well. So, looks like I should get another 30K out of it but if not, simple to remove and do again! Seems no more banging that head/trim panel to get the fan to come on. Thought there was a second tutorial for this HVAC head repair but couldn't find it in my doc collection... .
Thanks for this. I'm about to install a 'New' used one in mine for the same reasons. Couple of questions if you don't mind..does the cage for the radio need to come out too?
When you say the two pins were bear what 2 pins?
Also on the back of the area selector **** defrost, feet, etc what do those 2 long plastic connector type things attach to?
I haven't took it out yet so just wondered before I go ahead with it.
Thanks!
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Re: HVAC Head repair
Excellent thanks. I don't have an aftermarket radio so all good. Not looking forward to trying to reattach the pins now!
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Re: HVAC Head repair
Thanks for that. Not sure whether to try to repair mine. The direction of the air control is ok in most places although there's not much difference between face level and defrost...so that maybe something. The fan speed is very irregular and I thought I'd try this first before replacing the resistor. So mainly the fan speed and the air con isn't kicking in and before having the compressor looked at I have heard that the relay for the a/c...or lack of it is in fact the button on the controls.
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Re: HVAC Head repair
I have had three radios in my car, an OEM radio, a Kenwood single DIN which used a sleeve and a Kenwood double DIN which also uses a sleeve.
The sleeves are actually the same size as the OEM radio outside dimensions and when inserted can be made to locate in clips used to hold the OEM radio. The sleeves I have had butt against the lip that surrounds the radio opening in the radio/AC bezel, so the sleeve has to be released from the radio mounting clips, this can be a bit tricky as the clips holding the sleeve may not be obvious as there are a number of clips that can be bent to locate the sleeve. The sleeves come with a number of clips that can be bent to clip to the radio opening pocket, maybe mark the ones you use.
The sleeve if there is one, has to come out so that the radio/AC bezel can come off. This bezel is held on with clips and two screws which are located in the top face of the bezel radio opening. The screws actually can be removed prior to removing the sleeve. Remove the screws and with a plastic trim tool carefully pry off the bezel, start about 1.5" up from the bottom on both sides which is where the two clips are.
The square white plastic control rods locate in square holes in the back of the round selector *****, make sure they are correctly located radially or the ***** will not make the correct selection of heating or cooling. Prior to removing the bezel note the position of the selector ***** and replace it in the same position, do not rotate the square rods. These rods have swivel joints on them and are liable to sag or get out of line if they are touched, make sure they are in the square holes in the back of the ***** before you reassemble it all. Someone put it all together with one **** not coupled to the rod, a lot of time wasted on that mistake.
I think this time I will do the mod on the board location as I am over half way from being able to take it out again.
The above is what I noticed when I was and still am playing around with these parts.
Last edited by onehundred80; 04-19-2019 at 10:13 AM.
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Re: HVAC Head repair
The cage is called a sleeve I think.
I have had three radios in my car, an OEM radio, a Kenwood single DIN which used a sleeve and a Kenwood double DIN which also uses a sleeve.
The sleeves are actually the same size as the OEM radio outside dimensions and when inserted can be made to locate in clips used to hold the OEM radio. The sleeves I have had butt against the lip that surrounds the radio opening in the radio/AC bezel, so the sleeve has to be released from the radio mounting clips, this can be a bit tricky as the clips holding the sleeve may not be obvious as there are a number of clips that can be bent to locate the sleeve. The sleeves come with a number of clips that can be bent to clip to the radio opening pocket, maybe mark the ones you use.
The sleeve if there is one, has to come out so that the radio/AC bezel can come off. This bezel is held on with clips and two screws which are located in the top face of the bezel radio opening. The screws actually can be removed prior to removing the sleeve. Remove the screws and with a plastic trim tool carefully pry off the bezel, start about 1.5" up from the bottom on both sides which is where the two clips are.
The square white plastic control rods locate in square holes in the back of the round selector *****, make sure they are correctly located radially or the ***** will not make the correct selection of heating or cooling. Prior to removing the bezel note the position of the selector ***** and replace it in the same position, do not rotate the square rods.
I think this time I will do the mod on the board location as I am over half way from being able to take it out again.
The above is what I noticed when I was and still am playing around with these parts.
I have had three radios in my car, an OEM radio, a Kenwood single DIN which used a sleeve and a Kenwood double DIN which also uses a sleeve.
The sleeves are actually the same size as the OEM radio outside dimensions and when inserted can be made to locate in clips used to hold the OEM radio. The sleeves I have had butt against the lip that surrounds the radio opening in the radio/AC bezel, so the sleeve has to be released from the radio mounting clips, this can be a bit tricky as the clips holding the sleeve may not be obvious as there are a number of clips that can be bent to locate the sleeve. The sleeves come with a number of clips that can be bent to clip to the radio opening pocket, maybe mark the ones you use.
The sleeve if there is one, has to come out so that the radio/AC bezel can come off. This bezel is held on with clips and two screws which are located in the top face of the bezel radio opening. The screws actually can be removed prior to removing the sleeve. Remove the screws and with a plastic trim tool carefully pry off the bezel, start about 1.5" up from the bottom on both sides which is where the two clips are.
The square white plastic control rods locate in square holes in the back of the round selector *****, make sure they are correctly located radially or the ***** will not make the correct selection of heating or cooling. Prior to removing the bezel note the position of the selector ***** and replace it in the same position, do not rotate the square rods.
I think this time I will do the mod on the board location as I am over half way from being able to take it out again.
The above is what I noticed when I was and still am playing around with these parts.
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Re: HVAC Head repair
Just the radio, then there are 2 (two) screws up under the lip where the radio was, that need to come out. That radio trim (with the whole bottom switch set (all 6 switches) come out. Bottom first, then the top of that trim gets pulled down to allow the two top clips loose. Then pull out the trim bottom side first, and the top part will come off in a downward direction (two clips secure it along the top of the trim that will need to come off in a downward motion). The two pins I was talking about are the two dial selection (ductwork air direction flow) that come out of the HEAD and slip into the two shaft pins behind the HEAD, that direct the air flow. I would put the right dial at maybe 12 or 6 position then DO NOT TURN them or the ones behind the HEAD. If you do the ductwork will not match the flow position you select. I am not sure if they are keyed one way, so why risk not getting them in the right position? Make sure you get them lined up correctly, I had to reach one hand up inside where the radio slips in, to make sure the two shafts line up and slip into their shafts behind where the HEAD fits. Good luck fitting them correctly, when I was done I made sure they redirected the flow correctly, you'll select each position and check where the air is exiting making sure it follows the dial. Maybe you'll just select the 12/3/6/9 positions, but you'll be able to feel the flow from the ducts. .
Thanks so much for this, it's answered another question I had!
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Re: HVAC Head repair
Thought I'd just reply here after doing this today. Everything is so easy....And then you have to line the pins up! I've never swore so much in my life! What an absolute pain in the grass! I took the vent grill off above the controller for more access and still couldn't do it! In the the end I had my wife with her smaller hands in there and she managed to line them up after about 30 mins! So anyway all done and it's still not solved the irregular fan speed and air con not working! Oh well. Blower resistor and a trip to the ac shop!
Thanks for the help on this thread though. It did help a lot.
Ed
Thanks for the help on this thread though. It did help a lot.
Ed
Re: HVAC Head repair
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