['96 GLT w/ECC] Latest AC/REC light woes

s2zeller · Post by **s2zeller** » 29 Apr 2013, 21:39

My last experience with blinking AC/REC lights was almost 4 months back.

Now that it has warmed up, I want to use the AC on occasion but I'm running into some difficulties.

My ECC is set to AUT.

The driver's side vents have an issue when at approximately 72F. That is, it blows hot fairly consistently at this setting regardless of internal cabin temperature. The passenger side seems to be behaving itself.

When I drop the driver-side dial down below 72, the vents generally starts pushing out cold air (although not always).

If I set the dial too far down (i.e. just above 60F), then I start getting blinking AC/REC lights (though the air still is cool).

I do hear various motors/vents making adjustments in what sounds like a very smooth and unimpeded way.

When I tried the home-brew code reader, I get nothing at all. Does that mean no codes are being stored? I did have the occasional read problem last time around so I suppose it could be operator error.

I have yet to check the AC refrigerant level this year, so could that be a possibility (i.e. blink the lights but not store a code)? In each of the past two summers, I've had to put a can of refrigerant in the system (with last year having the AC on pretty much from March to October).

The sensors on the grab handles were cleaned out and lubed 4 months ago. The driver-side (under dash) sensor was replaced about 5 months ago.

Any help is much appreciated.

Post by **jreed** » 30 Apr 2013, 04:58

Great post! I like the clear description of the situation and observations.
When you try out the homebrew code reader, do you get "1 1 1" after you actuate the switch? If there are no codes, you should get "1 1 1" indicating all clear. If you don't get any signal back, then there may be a connector, wiring or component issue in the code reader/OBDII connector.
Based on your description, it may be that the Driver's Side Temperature Damper Motor, sensor or mechanical coupling is not working right. I'm going to guess that you will get one or more of the following codes:
"2 1 1" ("Driver's side damper motor position sensor open circuit or shorted to 12 volts")
"2 1 2" ("Driver's side damper motor position sensor shorted to earth")
"3 1 1" ("Driver's side damper motor shorted to earth or 12V")
"3 2 1" ("Driver's side damper motor active too long").

Good luck and let us know what you find for codes.

s2zeller · Post by **s2zeller** » 30 Apr 2013, 05:50

Thanks for the help.

I'm getting no codes, so I'll go back over the reader and check the wiring. The LED is lit when I don't have the ignition on and not when the ignition is on. I did notice that the two leads coming from the switch were not acting interchangeably (i.e. if I switched them between pins 5 and 6, then the LED would not go off). I'm supposing therein lies the problem, correct?

The AC/REC blinking lights only persist if I leave the temp dialed really cold (I need to verify that it is only the driver's side that is triggering this). That is, if the temp setting is moved back to 75 (for example), then the lights don't blink the next time I start the car.

Post by **jblackburn** » 30 Apr 2013, 13:08

Kinda sounds like a temperature blend door is hanging up or the motor *thinks* it is, perhaps due to dirty contacts. But that's only guessing based on your symptoms without the codes.

My s70 would clunk in the summer when the AC was on and it was set to 68 or below. The blend door would get hung up on something on the "full cold" setting.

Try out this link if you want to dive into it: https://www.matthewsvolvosite.com/forums ... =1&t=27239

Post by **jreed** » 30 Apr 2013, 13:18

Yes, that might be the problem. I don't think the two leads are interchangeable. I had good luck wiring it up as shown in the diagram here:
https://www.matthewsvolvosite.com/forums ... 43#p251189

s2zeller · Post by **s2zeller** » 05 Jun 2013, 19:41

Well, I finally got around to looking at this. Last Sunday, I read (and cleared):

1-4-1: Driver’s Side Temp. Switch Faulty Control Signal
3-2-1: Driver’s Side Damper Motor Active Too Long

The blinking AC/Rec lights came back pretty quickly and I just pulled:

1-4-1: Driver’s Side Temp. Switch Faulty Control Signal

I take it that this is the temp SELECTOR switch on the ECC, and that I should probably replace the ECC (I looked inside some months back and didn't see anything obviously amiss).

Post by **abscate** » 06 Jun 2013, 02:42

I think I would try replacing the driver side blend motor, not the ECC.

s2zeller · Post by **s2zeller** » 06 Jun 2013, 05:56

You are refering to the lower of the two driver-side motors?

I do have a spare for that one (since I did get the old one to start functioning - at least for a while -after regreasing it), so that is probably worth a shot.

Post by **abscate** » 06 Jun 2013, 12:32

I dont know what I was smoking, but you were right about the ECC probably being at fault for that 1-4-1 code.

Sorry about that.

s2zeller · Post by **s2zeller** » 06 Jun 2013, 13:13

Maybe having gotten the 3-2-1 in the initial set of codes... ?

I'll probably check the codes again this weekend to see if it just sticks to 1-4-1.

If 3-2-1 reappears, then I'll probably swap out the motor just to rule that out.