Climate Control (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

D

Docmallory

Guest
Many people hate the Climate Control in the LX and 40th Anniversary. (Many don't.)

Several have talked of the prospect of swapping in a manual control panel/unit.

Prior threads have also mentioned the "A/M" (presumably for Auto and Manual) switch in the back, and that the manual units appear to have the auto function already built in to some extent.

As far as I know, however, no one has done a side by side comparison -

I bought a used manual HVAC control from a '93 to swap into my 97 40th. The climate control on the 40th was bugging me, as it only had two settings, 100% cold and 100% hot. :mad:

Well, it turns out that the control box for the 93 manual is exactly the same as the 97 climate control. All that is different are the face plate markings, the blank over the AUTO button on the 93, and a snap-in temp sensor on the 97 CC model (which also readily snaps into the 93 manual box). All the innards look exactly the same, the circuit boards share the same part number, and the connectors have the same number of pins.

This confirms that there should be no modifications needed to change the Auto Climate Control to manual mode other than flipping the switch on the back, because then it would basically be identical to a truck with the manual controls (other than the now unused sensors attached).

Also, I think the reason my auto CC mode wasn't working well was because the cabin temp sensor was unplugged (apparently from my earlier forays into the dash to install CDL and re-locate some switches.) It was also extremely dirty, so I blew it off with compressed air and re-installed it. This seemed to fix the all or nothing temperature problem.

As for a functional comparison between the 93 box and the 97 box, I have not yet had time, due to some technical problems with the 93 box and a wife who was bitching at me for working in the garage at 11PM last night. :doh: :doh: :doh:
 
Last edited by a moderator:
Thanks for the info, the CC is my biggest complaint about the Cruiser, I am planning a CDL so maybe at that time I will go manual, thanks again for the info, I know what you mean about the wife......only been married a year and she already asks, "what are you doing out there" good luck
 
This is good information!

How much can us manual folk expect to pay for a used auto CC unit? I bet the wifey would love this mod!
 
The Climate Control in my LX450 has a temp sliding knob that I can set the desired temp to (approx). Worked fine in the summer and so far so good in the winter.
 
Docmallory said:
This confirms that there should be no modifications needed to change the Auto Climate Control to manual mode other than flipping the switch on the back, because then it would basically be identical to a truck with the manual controls (other than the now unused sensors attached).
Click to expand...

Do you have more info on the switch to flip? Any pict of the switch?
 
I love my climate control...just set it and leave it alone..if u mess with it it does not work good
 
This would be sweet! I love my wife's Maxima...leave it set to 75 and never have to really mess with it.

I have noticed the "blank" button on my 94...is this what your talking about?
 
the temp sensor is behinf the 3 slotted grill correct? is it safe to blow it out with compressed air without taking it apart or is there soemthing fragile in there?
 
sorry 4 slots, took a flashlight an looked inside there is a lot of dust in there cant see what is under it, is there a fan or soemthing that draws air across it? hwo did all that dust get in?
 
Doc said:
This is good information!

How much can us manual folk expect to pay for a used auto CC unit? I bet the wifey would love this mod!
Click to expand...

Well, all we know is that to go from a climate control truck to go manual settings you need only flip a switch.

However, to go from a manual truck to a climate control set-up, you'd need the sensors. I know the cabin temp sensor wire does not go directly to the HVAC control box - instead it goes back into the wiring harness. Where it goes from there is anybody's guess. There is aso supposedly a sunlight sensor that mounts to the top of the dash and I think an outside temp sensor up front behind the bumper. There may be other things needed - I don't know.

You'd also need to remove the blank off your Auto button and put the appropriate button cover on there. Faceplate trim is only important if you want the numbers. Otherwise you could keep your red/blue lines.
 
Last edited by a moderator:
RavenTai said:
sorry 4 slots, took a flashlight an looked inside there is a lot of dust in there cant see what is under it, is there a fan or soemthing that draws air across it? hwo did all that dust get in?
Click to expand...

It looked like a little light bulb. Nothing too fragile. There's a 3/4 inch white corrugated hose that connects at the back, and my best guess (could be wrong) is that it draws air, sucking it in through the 4 slots. I say this based on the amount of dust mine had - something has to be drawing/pushing air to accumulate that much dust.

I would not be too afraid to use compressed air (like from a can, not a compressor) to spray through the slots. Taking the dash down involves 4 screws, and once the back is accessible, you can just pull out the plastic housing that contains the sensor. You'll know where it is by the two wires and white tube that lead to it. The little housing just snaps into the HVAC control unit behind those slots.
 
TX_TLC said:
I have noticed the "blank" button on my 94...is this what your talking about?
Click to expand...


Yes, but see my reply to Doc.
Funny thing is, on a Auto CC truck there are a couple of green/whote LEDs that show the status of the Auto function. Manual control trucks have these as well, and they light up all the time too - you just can't see them because of the blank.
 
medtro said:
Do you have more info on the switch to flip? Any pict of the switch?
Click to expand...

It's very easily found onthe back side of the control unit. You have to pull the dash apart, but it is easy.

If you take down your dash (you'll probably need to have the gear selector in Drive or 2nd to have enough room), you'll see 4 pieces of clear tape on the back of your HVAC control unit. These pieces of tape are covering holes - 3 round holes and a small rectangular hole/slot. Peel the tape off the rectangular hole/slot and inside is a little switch. Beside the slot are the letters A and M. Switch it to M with your finger tip or whatever fits into the slot. Tape it back up, or else the HVAC control unit will have an opening for dust/dirt to enter and land on the circuit board.

To remove the dash panel on a 95-97: Two hidden tabs inside the little business card-sized cubby (cupholder slot), then two screws behind that. Two screws behind the ashtray. Then just gently pull the whole panel off. It has a few pressure clips holding it on.

EDIT: Here's the switch, seen from the back, wth the tape still over it. If you want to leave the tape intact, you can pop the back cover off the control box (only 3 tabs keep it in place), flip the switch, and replace the cover. The three round holes are where the night-time illumination bulbs are located. These are easily replaceable, and I would advise taking the cover off rather than trying to access them through these holes.
hvac.jpg
 
Last edited by a moderator:
Docmallory said:
It looked like a little light bulb. Nothing too fragile. There's a 3/4 inch white corrugated hose that connects at the back, and my best guess (could be wrong) is that it draws air, sucking it in through the 4 slots. I say this based on the amount of dust mine had - something has to be drawing/pushing air to accumulate that much dust.

I would not be too afraid to use compressed air (like from a can, not a compressor) to spray through the slots. Taking the dash down involves 4 screws, and once the back is accessible, you can just pull out the plastic housing that contains the sensor. You'll know where it is by the two wires and white tube that lead to it. The little housing just snaps into the HVAC control unit behind those slots.
Click to expand...


a light bulb lookign thing? now you have me curious as to how it works, I was expecting a thermistor. I do not have the canned air so I will turn down the regulator on my compressor, my CC seams sluggish to react sometimes, seams to overshoot also. think the dust may be part of i, insulating the sensor/bulb keeping it from seeing changes
 
One more thing - I had driven around a bunch today and my set-up (which is now switched to manual mode) worked well. Note that when the switch is flipped to Manual on a unit with the Auto button, the Auto button still illuminates (yellow). If one presses the Auto button, it will light up green, but all the fan buttons turn off and it does nothing.

So, when in Manual mode, the Auto button still lights up, but Auto mode will not work.


Just for completeness sake, does anyone with a '97 EWD know what sensors are involved with the Auto CC, and how they are routed?
 
Last edited by a moderator:
in the 96 LX ewd it shows the "AC Solar Sensor" and 4 temprature sensors,

"AC Thermistor", (on the evaporator)
"AC Ambient Temp Sensor" (Outside Air Temp, behind the bumper)
"Water Temp Sensor" (on the heater core)
"AC Room Temp Sensor" (in control pannel) .

All 4 are wired to the "Automatic AC Amplifier", the Auto AC Amp is located just foreward of the ac control pannel, there is also a "AC Amplifier" near the glove box. I assume the manual AC vertions will just have that box. there is also a coolant temp switch in the block that interupts the AC clutch through a relay directly, neither the "AC Amp" nor "Auto AC Amp" are in that loop
 
Last edited:
just figured out something,

when I start up on a cold morning even with the slider all the way to 85* the fan does not turn on, it waits until there is heat to blow, I though it was a timer or something, but no it must be watching the temprature of the heater core and waits until it is warm to kick on the fan, that is one nice feature of the automatic AC. you dont have to wait with the fan blowing cold air on your feet. I hated that in past auto's

I'll keep it in Auto hopefully cleaning the sensor will make it more rsponsive.
 
...Except those of us in cold climates don't get airflow until it warms up, which means a fogged windshield until things warm up. Or manual mode so you can keep the w/s clear during warmup.

DougM
 
...Except those of us in cold climates don't get airflow until it warms up, which means a fogged windshield until things warm up.
Click to expand...

On mine if the defrost button is pushed the fan runs right away.
 
You must log in or register to reply here.

Similar threads

K
80-Series Climate Control Question...
Replies
6
Views
874
Mrtwooooo
Mrtwooooo
Box Rocket
Climate controls unit repairs?
Replies
9
Views
1K
reklund5
reklund5
T
1990 VX 80 series climate control actuators
Replies
1
Views
666
SNLC
SNLC
OffRoadScott
  • Question
AC climate control panel
Replies
3
Views
1K
Ronald Rooij
R

Users who are viewing this thread

Total: 2 (members: 0, guests: 2)

Share this page

Back
Top Bottom