climate control system

[dkrace67]

I have a 95 Park Ave with a dual electronic climate control system, sometimes (very intermittant) it will blow out ice cold from one side and hot from the other. When this happens the set temperature blinks. My owners manual says when that happens to bring it to a service center. Does anyone have any ideas/suggestions?

[96Rivman]

Maybe you should just bring it to the dealer. They have the right equipment to check all that HVAC stuff.

[dkrace67]

spoken like someone with more money than time...

actually, I run a repair shop so in essense, I am the "dealer"...just at a much reduced labor rate. I haven't had to deal with this issue yet and instead of replacing components (one that lists for $631, the culprit I suspect, and another that lists for $526) I thought I would do a little research first and try to learn something...

[kaspr]

This exact problem actually started occurring on my Park Avenue about a month ago. I suspected it was the climate control module, as well, so I bought one and installed it... same problem. So I'm in the same boat as you, but I assure you that it's not the module... which is bad news since you can get a decent module from a junk yard for $50 or possibly less.

[deadring]

dkrace67,

dont go to a dealer for nothing,

IF i am right, and this should work on yours as well..

on the climat control, you push OFF and WARM at the same time for about 2-3 seconds.. it should go into trouble shoot mode and give you an error code , just like thre EFI with the "check engine light" blinking.. exept it will REALLY displays a code IF there is something wrong.. if it'displays 00 then it does not detect anything OR you have no problems there

deadring

[dkrace67]

deadring,

Thanks! I'll do that tonight. My friend has the factory manuals for his '96 Riv that has a similar climate control system. The error codes are listed in it so if your technique pops them up I'm set.
We also were going to try plugging our Snap On scan tool into the OBD port but I'm not sure the climate controls will come up in the diagnostics...

I'll keep you "posted" (pun intended, unfortunately...so sorry)

[kaspr]

Thanks for the suggestion, deadring. I just tried the technique of pushing OFF and WARM at the same time, but it didn't put it into troubleshoot mode. It didn't display 00 either. Any other suggestions, I'm all ears.

[dkrace67]

Exactly, I couldn't get it into troubleshoot mode either, and (unfortunately) my scan tool doesn't allow me access to the climate control systems computer (or subsequent codes).
I was playing around with it a bit and I noticed that upon power up (just turn the key on, not necessarily starting the vehicle) the motor for the driver/passenger damper appears to go through a "homing" routine. Strange thing is, once it reaches full travel in one direction, it continues to try and move. Like it's driving itself in the same direction because it doesn't know it's reached the end of travel. I physically move the damper back a bit and it continues in that same direction, right back to the limit. After several times of this routine, it finally stopped and went back the other direction to that limit and continued to move against that limit. Finally, after a minute or so, it gave up and returned to a central position for what I can only assume is the preset temperature. After all that, it appeared to operate normally (i.e. - I could set the temp control and it would move accordingly). But, once I cycled power, the same behavior returned. The motor will continue to drive itself all the way to one end of travel, disregarding the preset temperature (which I left at around 72).

[deadring]

ok,

maybe i didn't explained it right.. it lacked detalis i must admit

here is the REAL way taken from another post in the forum

This method uses several common commands in all stages of the "menus" :
"HI" = proceed forward
"LO" = move backward
"WARM" = up
"COOL" = down
"OFF" = back one level
"AUTO" = exit ECC diagnostics/override function.

1) With the key in "run"
2) Press"off" and "warm" at the same time on the control head.
3) First, it will check all the segments.
4) Then codes will display.
"00" idicates that no codes are present. A "1" prefix indicates
that the code is history, not current.
5) There are too many codes to list, but look for a 41 or 141 - this is
the passenger side air mix actuator circuit. If this code is present, you
can narrow your diagnostics down considerably.

That's where the factory service manuals come in handy. Here's what the codes mean:


DTC Description
DTC 10/110 Ambient Temperature Sensor CKT Open or Shorted
DTC 13/113 In-Vehicle Temperature Sensor CKT Open or Shorted
DTC 15/115 LH Solar Sensor Circuit Open or Shorted
DTC 35/135 E & C Data Line Failure With Heater and A/C Control Assembly
DTC 38/138 Serial Data Line Failure With PCM
DTC 40/140 Driver Air Mix Motor CKT Open or Shorted, or Not Calibrated
DTC 48/148 Long Term Freon Loss
DTC 52/152 Keep Alive Memory Lost: Sets With Battery Disconnected
DTC 66/166 Low Freon

NOTE: A number 1 prefix on any diagnostic trouble code indicates a history DTC.

This indicates no freon (more than likely a leak somewhere in the system), and a faulty calibration of an air mixer. The 52 will set if the battery is disconnected and is no big deal. You will need to find and correct the reason for no freon before you can procede.

from who ever made this post originally i thank him and i only quoted his words because someone needed it.... i claim no credit for it neither :P


hopes this helps guys, i confirm it works on my PA 92 and i'ves seen it work on 93 and even higher i believe.

sorry again for misinforming you guys

Deadring

[dkrace67]

deadman,
Thanks for the additional info. Unfortunately, with the key in run, pressing off and warm at the same time did not display any codes. The only thing that happened was (after several attempts) the outside temperature started blinking (45, not one of the codes listed on your menu).

kaspr,
Exactly which unit did you replace? The head unit (with the buttons on it) or the module under the dash (kind of above the whole heating assembly etc.)? I am wondering if I should try replacing the motor/actuator unit that controls the passenger side temp. Maybe it has indeed "lost it's bearings" or position. Perhaps there is an encoder or indicator of some sort inside that is intermittent or slipping.

[deadring]

i dont see why the codes don't dispaly... did you press them long enough? it does take a few seconds..and you do have to press them at the SAME time..

deadring

[dkrace67]

I don't know why they didn't display either. I held them for about 10-15 seconds, and I tried various other combinations (i.e. - off and cold, off and auto, auto and warm etc. etc.)...trust me, I WANTED that to work, bad! I wonder if there is just too great a difference between a '95 and a '92. You wouldn't think so, but I've seen stranger things. My friend (who gave me a hard time in this thread - see 96Rivman) has the same system in his Riv, so I think I'll have him try it tonight. Perhaps the reason it doesn't work is because the module has failed...that's another possibility I guess.

[deadring]

well me i do it with the engine running and i press on OFF and WARM at the same time for about 5 seconds or so.. and then it all lights up for a 1 second, then shows codes.. well mine shows 00 flashing, saying that there are no codes


maybe there is another way on the 95+ models..

maybe someone else can jump in and help out?

anyone?

deadring

[cheapertofixit]

I also have a 95 PA with Climate Control problem. The outside temperature indication has been slowly increasing over the last few weeks to a high today of 118 degrees F. Its been in the fifties all week! After reading your posts. I tried to get the error codes to no avail. I have no idea(and can't find) the locations of the sun and exterior temperature sensors to inspect, nor can I aquire the codes much like yourself, to troubleshoot.

[deadring]

cheapertofixit, well thats an easy fix or easy finding the source of the problem.

look at your outside temp sensor.. pop open the hood and look BELOW IN FRONT of the radiator- AC radiator assembly.. i got a 92 and if you look down where th both rads are, you should see a black cable to which there a small plug on it with a little black sensor.. thats a outside temp sensor..you can't miss it. if you look at your radiator, i'ts center bottom ...theres a gutter like thing there where it hangs.


as for you other guys, i dont what i can say.. maybe ask Tman or parkavenue chrome , they seem to know alot about PA's

deadring