Hi guys, I'm new to Volvo's although not new to working/tinkering with cars.

I have a 1997 960 that has a few issues I want to address.

First:
The a/c does not work:


- pressing the a/c button does not light it up, should it?
- whether a/c is on OR off, changing temperature does not seem to affect anything, air coming out of vents is always hot

Based on that, I am wondering if there are two issues, a/c doesn't even engage (I don't hear the click or fan come on when pressing a/c button), and also if the temperature adjustment is broken.

What steps can I go to verify this?


Second issue:
My gauge cluster looks like this:


There is a snow button on the lower left that the manual I have doesn't show. It's always illuminated, do you know what it is?

 

AC button pushed down (Compressor is activated) is illuminated blue. Two possibilities: either the light-bulb is burnt, or the AC Module (shown in your photo) is not functioning correctly. Some of these units suffer from cracked soldered connections, which can be seen with a magnifying glass, and re-flowed.

Regardless of this, there are two basic tests: what is (are) your pressures? You can tap into the low pressure line at the firewall (screw cap on). Second test is to unplug the Cutoff switch at same location, jumper the two wires on the connector, which should turn on the Compressor.


That's a warning light for slippery conditions, and only illuminates when outside temperature is between 22 to 37 degrees F. It also means that you have the winter package option in the car (good thing)-- heated seats, and most importantly a Automatic Locking Differential for better winter traction.

 

I appreciate the reply. I found that the ambient air sensor is missing (I think the shop that repainted the front/rear bumpers took it off and forgot to put it back on). I found a used one and ordered that so that should fix that issue.

For the A/C, you were right, there is a blue light, but I just couldn't tell it was on. However, there is still no A/C. For the connector you say to jump two wires, this connector is close to the firewall where the low pressure pipe is? I turned key ignition to on, and tried to listen for any click when turning a/c on but do not hear it, leading me to think the a/c isn't engaging? (or does it click only if engine is running - belts spinning on a/c pulley).

 

I am not sure why body shop would touch that sensor, actually mounted on the slots at the Condenser's air guide (black plastic).


Engine running, jumper the two terminals on the connector to the Low Pressure Sensor. This should activate the compressor. LP Sensor is located on the Accumulator / Drier. It's the only thing there with a connector to it. Just unplug the connector and jumper the two leads (On the connector).

What is your Low Pressure (psi)?

If compressor works, good news. Then bad news -- you need to check for leaks, since refrigerant might be low. The function of the LP Sensor is to cut-out and cut-in the compressor, on the basis of low pressure readings.

 

Thanks, I am going to try that today when I get home. I'm almost hoping it's the first issue then so I can just replace the a/c rather than try to find a leak.

 

On a side note, I see that when turning key to ignition position, the a/c light comes up and then turns off. I thought I remember reading somewhere that this indicates a problem with the a/c? It will either do a long blink like what I have, or shorter ones to indicate the problem? Do you know what the long single blink of the a/c light means?

 

Replacing the compressor is a difficult job. It's much easier to replace any other component that can leak refrigerant.

 

Yep: that light flashing means that there is a fault. Here is an excerpt from the Manual:

"The EEC system incorporates a self-diagnostic function that
indicates system faults through a series of trouble codes. The
presence of fault(s) is indicated by flashing A/C OFF button. The
control panel is programmed to enter a pre-programmed mode when a
fault is detected. Under fault condition, control panel ignores the
faulty signal, selects an alternative pre-programmed value and
prevents delivery of faulty output signals.
Entering Self-Diagnostics

1) To enter mode, ensure engine is running. Shine a nonfluorescent,
bright light on solar sensor. Place blower fan control
**** in AUT position and function selector **** in vent position.

2) Place temperature control **** to maximum cooling
(pointing straight down). Ensure recirculated air switch is depressed
and A/C OFF button is released. Depress and release A/C OFF button
within 5 seconds to start self-diagnostic mode.

3) Each fault code consists of 3 digits. For example, Code
132 is displayed by a single flash of the A/C OFF button for the first
digit (number 1). After a pause, the second digit of code (number 3)
is indicated by 3 flashes. After another pause, the third digit of
code (number 2) is indicated by 2 flashes. See TROUBLE CODE
IDENTIFICATION table.

4) Three different fault codes may be stored in memory.
However, only one code may be displayed upon request. It may be
necessary to request display of fault codes a number of times to
ensure all fault codes are displayed.
Exiting Self-Diagnostics & Clearing Codes
To exit self-diagnostics, turn ignition off. All codes are
cleared when ignition is turned off. Fault codes are not stored in
memory. Even if a code has occurred several times during a period of
time, code will only be stored until ignition is turned off.


TROUBLE CODE IDENTIFICATION TABLE

Affected Circuit/Sensor Code
Fault Free System .................................... 111
Outside Temperature Sensor
Short Circuit To Ground ............................ 121
Open Circuit Or Short Circuit To 12 Volts .......... 122
In-Vehicle Temperature Sensor
Short Circuit To Ground ............................ 131
Open Circuit Or Short Circuit To 12 Volts .......... 132
Water (Coolant) Temperature Sensor
Short Circuit To Ground ............................ 141
Open Circuit Or Short Circuit To 12 Volts .......... 142
Alternator (D+ Signal Fault) ......................... 151
Solar Sensor ......................................... 161
Servomotor/Potentiometer
Open Circuit Or Short Circuit To Ground ............ 211
Short Circuit To 12 Volts .......................... 212
Servomotor
Incorrect 12-Volt Supply To Pins No. 17 & 18 ....... 213
Servomotor
Fails To Operate Within 10 Seconds ................. 214
ECC Control Panel
Faulty Temperature Control ......................... 231
Fan Motor Excessive Starting Current ................. 233
Power Unit - Incorrect 12-Volt Supply
Affected Output:
Coolant Valve .................................... 241
Bi-Level ......................................... 242
Vent ............................................. 243
Recirculated Air ................................. 244
Defrost .......................................... 245
Floor ............................................ 246
Fan (Maximum Speed Relay) ........................ 247
A/C Compressor ................................... 248
Radiator Fan Relay ............................... 249

 

Hi. I have a similar issue with my 960 wagon. I'm getting the code 132 every time I do the diagnostic, and sometimes I also get 161, but it's not consistent.

I'm not sure where the in-vehicle temperature sensor is. Is it in the dome light? It says the "courtesy light fixture", which is not currently connected in my car. I have two of them in the garage but neither ever produced light when plugged in, and the heat worked fine all during that time. It was only until a week ago or so that the heat stopped working.

The controls work fine. Blower blows as needed, vents switch no problem. Recirculate actuates. No heat.

Not sure what to do at this point.

I took it to a local high-end garage and they replaced my thermostat, which didn't need replacing. They then wanted to look under the dash for three hours, at $115 per hour (!!!). I told them no thanks and took the car back.

Any thoughts?

 

Code 161 is for the Solar Sensor, which is on the outside of the minitower of Alarm blinking Light, facing the windshield, on top of speaker grille, on the dash right corner.

Cabin sensor is located at the Dome light. In-Vehicle Temp Sensor is on the heater box behind the radio.


First off, with warm engine, turn **** into heat, go outside on the engine compartment and measure vacuum at the heater valve. It should be 18-20 inHg.

Me jumping into conclusion -- I would suspect the ECC (Electronic Climate Control) unit to be faulty. Usually the culprit are its solder points. Cure is to re-flow solder if you can. Cheap fix.

Yes, code 132 points to coolant Temp Sensor which is mounted on the Heater core, yet you seem to have code 161 as well. To me, these seem random.

Again try measuring the vacuum at the Heater Valve. If vacuum is not present, which I think will be the case, push the shaft open yourself. You should start to get some heat.

 

I would also connect the cabin sensor (at dome light). Keep in mind that that sensor has a vacuum line as well, which should be connected.

If vacuum is not connected to it, there would be a leak and your Vacuum Controller might not be able to do its job, when heat is demanded, it may not open the Heater Valve, which would also explain why you are not getting heat.

Why vacuum line is connected to that sensor, one might ask -- it is using manifold vacuum to suck cabin air into the sensor resistor wire, thus measuring cabin temperature.

 

Thanks! That's awesome information. Where do I find the ECC? I have a solder gun and could make quick work of that job.

 

We re-connected the cabin light. The blinking code light now doesn't start blinking until about 30 seconds after the car starts. I've tried doing the Auto-vent-max-recirc thing at startup and it doesn't return any codes. So, not sure what's happening there. Anyway, I'm eager to try the solder solution.

 

ECC = Electronic Climate Control unit. That's the head-unit. The one with *****.

Did you test the Heater Valve first?

 

Hi. I just measured the vacuum at two places:

1. The "heat exchange water valve" which I believe is the thermostat? There was no vacuum at either the therm or the hose.

http://mikmuller.com/images/570_full.jpg

2. The other place I checked was what I think is the "non-return valve" that leads, after the Y, to the "engine intake manifold."

http://mikmuller.com/images/569_full.jpg

The Engine Vacuum gauge went to 17 inches for the manifold side. There was no vacuum below valve 31.


BTW, these items, and numbers, are taken from the following vacuum diagram.

http://mikmuller.com/images/571_large.jpg


So, I'm not sure which one of these two is the "Heater Valve", or if it's neither.

The next place I can check is the Vacuum Tank, but I can't locate it. Is there a diagram of the underside of a 1997 960 Wagon? I've seen photos of it, but can't find it under my car.

 

First things first -- Heat Exchanger Water Valve is also called "Heater Valve" or "Coolant Valve." It is not a thermostat.

This Heater Valve (# 37 in your Diagram) is a normally-open (I was wrong before) valve, and no vacuum is applied to it. Vacuum is applied when Temp Selector is at coldest setting. In that case, Vacuum is applied and Valve is closed.

So, you should not have any vacuum at the hose (there is never vacuum at the Valve's port). There should be vacuum 18-20 inHg when you turn Temperature **** to the coldest setting. This means ECC thru Vacuum Controller (# 21) is shutting the flow of hot coolant to the heater, to assist with cooling.


Correct. That's how it should be. Check out this photo with labels for every hose.


Vacuum Tank (# 22) is behind the glove compartment; see Figure 4 in this Document.

Your vacuum at 17 inches: check your accuracy. If accurate, that sounds to be in the low end of the spectrum. Run this test and tell us which Scenario is you.

 

Sorry, I must not have had the gauge on tightly. It reads 20, steady, so I guess scenario 1.

We're unscrewing the glove box now. Man, I hope this is it. It's getting pretty cold out, lately.

 

I tested the vacuum at the heater valve while on max cold and also got 20 there.

So, we removed the glove box and the shield below it to get to the tank, and while I couldn't find the hose connector there, we did notice that as we mucked about with the wires, we suddenly started to get some heat. Not hot, but certainly not cold.

A close visual inspection of the tank from our vantage point of the passenger seat, and from below, found that it looked new and unmolested.

So... it's looking like the soldier points on the back of the ECC, or the solenoid. Are the soldier points obvious?

Henry, your help has been invaluable so far. Thank you so much.

 

With a magnifying glass you should be able to see cracks on solder joints of the circuit board. Recently there have been threads on this Forum on how-to remove it.

You should also check the Vacuum Controller (with multiple hoses coming in-and-out of it). Given the fact that some heat came on, it sounds like some connections could be loose.

Did you re-connect the cabin sensor's vacuum line?

Here is the parts diagram with the exact unit you have.

 

Yes, we got the cabin light back in. We cleaned out the sensor and reconnected the line.

I'm having trouble pulling the dash frame. I found the two screws behind the ash tray, and pushed in the tabs on the inside cavity where the stereo lives, but can't find the screws or whatever is holding the whole frame unit below the ECC.