[Dr.AD]

Originally Posted by supremeBaleno

We have a Swift-Zxi with ACC and yet I have always preferred the manual mode for atleast a couple of reasons : ACC mode goes with FreshAir mode, while I prefer Recirculate mode. Also sometimes I found it getting warm inside - never tried investigating the reason though. But anyday give me the Baleno a/c - switch on and get chilled interiors instantly.

Even I like the recirculation mode. But I think you don't have to go to full manual mode just for that. I keep the auto mode, and just press the recirculation button to keep it on recirculation mode, and it remains there while everything else (i.e. temperature setting, fan speed, airflow distribution through all vents etc.) remaining in auto mode. Thus, I think it is possible to overwrite the "recirculation or fresh air" choice without having to go to full manual mode.

If you really like to chill the interiors, then even in ACC systems you can go to manual settings with full fan speed and lowest temperature setting and effectively feel the same chill as you do in any normal (i.e. non-auto) AC. Thus, I would still prefer the ACC over a non-auto AC because here I can get the best of both worlds.

[S5157]

Originally Posted by SirAlec

please check, if the cabin temp sensor vent is not blocked.

if they are clean get the sensors checked.

this is an image shot from a swift zxi manual. i am sure SX4 also has it somewhere.

hello Sir Alec,

As per MASS they have checked it.The car was with them for four days for this issue.

Originally Posted by Zero Cool

Actually when the cabin reaches the desired temperature the fan speed slows down. but when due to rains or some other reasons there is a sudden drop in temperature and the cabin temperature is more than the ambient temp. the compressor also stops working. i also have the same issue in my sx4. i guess its a shortcoming of the acc by maruti.

so nothing seems wrong in your car. cheerios.

Hello Zero Cool,

Yes I agree there are no mechanical issues with this car.The pre VVt models doesn't seem to have this issue.I have tested this on a 2009 March Non VVT SX4.If i use the manual option in AC i dont have this problem.But the whole point of buying a car with ACC and the additional amount you have invested is getting waste for somebody else mistake or incompetency.

Originally Posted by Dr.AD

Yes, I have the exact same "issue". Incidentally, my car is also July 2010 SX4-ZXi.

I have the exact same experience as you, and I am also wondering if the logic that decides the temperature of air being blown is messed up in SX4's ACC. I am pretty happy with the cooling capacity of the AC (and all those who have traveled in my car have agreed that the AC is very powerful), but the temperature settings on the knob often does not make sense.

.

Hello Dr.AD,

I have noticed another cooling issue with my SX4 . If the outside temparture is 31 degrees and if the AC is set for 23, it takes almost 25-30 minutes to get the interiors cool and the Blower to calm down.It makes the loud noise as if it is a Vaccum cleaner at full blast. I have tried by lowering the windows for five minutes after switching on the AC but no luck.I have tested the same with a non VVT sx4 under same conditions and it cools down and blower gets quite in 10-12 minutes.

Also I have found that during the above situation when blower is at full speed the compressor get switched off and restart several times. I could make it out by listening to the audible click sound the compressor makes while switching on and off.

I have got a update from Territory Service Manager that a trained SX4 mechanic will visit my residence today to insepct the car for this ACC issue and "n" number of rattling issues on the car.

I will keep you all posted on what are the results.

[gavinimurthy]

I travelled 400 Kms yesterday in blinding rain throughout. The outside temperature was hovering between 22 to 23 degrees. The ACC was kept on auto and the dial was set to 22 degrees. I have nothing to complain about.

For getting the same comfort level every time try keeping your temperature setting at least one degree below the outside temp displayed. Even in the house if the room temperature is 22 degrees and if your ac is set for 25 degrees you will feel uncomfortable since the compressor won't turn on. The comfort level is dependent on two factors. The temperature as well as the humidity. If the compressor doesn't get activated the humidity will build up and you will start feeling uncomfortable even when the temperature seems to be o.k.

So in hot and humid climates like ours it is necessary that your ac setting is slightly lower than the room temperature. Same is the case with ACC in cars. You will feel very comfortable at 25 setting if the outside is 30 degrees. However if the outside is 22 and your setting is 25 degrees you won't feel comfortable. To get the same comfort levels as (30,25) you need to go for (22,21).

Murthy

[Dr.AD]

Originally Posted by S5157

Hello Dr.AD,

I have noticed another cooling issue with my SX4 . If the outside temparture is 31 degrees and if the AC is set for 23, it takes almost 25-30 minutes to get the interiors cool and the Blower to calm down.It makes the loud noise as if it is a Vaccum cleaner at full blast. I have tried by lowering the windows for five minutes after switching on the AC but no luck.I have tested the same with a non VVT sx4 under same conditions and it cools down and blower gets quite in 10-12 minutes.

Actually I haven't yet faced this. Well, I haven't driven much in outside temperature of 31C yet (except for some short drives). Since I got the car in July-end, the temperatures have been hovering around 25C in Bangalore (at least in the mornings and evening; I rarely drive around noon). My observation is that if the outside temperature is at 25 to 27C, and if I set the interior temperature to 23C, then the blower settles down in about 10-15 minutes. That seemed normal to me. Next time I get a chance to drive around in 30+C temperatures, I will note this and let you know.

Also I have found that during the above situation when blower is at full speed the compressor get switched off and restart several times. I could make it out by listening to the audible click sound the compressor makes while switching on and off.

I face this issue too. In general, regardless of the temperature settings, the AC compressor switches ON and OFF too frequently, and it does get a bit annoying. In fact, the worst time for this is when the ACC unit has settled down on the set interior temperature. In this situation, the compressor keeps switching ON and OFF with a time period of something like 2 seconds, which is very annoying.

I have got a update from Territory Service Manager that a trained SX4 mechanic will visit my residence today to insepct the car for this ACC issue and "n" number of rattling issues on the car.

I will keep you all posted on what are the results.

Hope the trained mechanic visited you and everything went fine. Please keep us posted.

[S5157]

The car is with MASS now and they are looking into the issue. Will keep you all posted on progress

[S5157]

The car is finally back from MASS. I have driven it for around 350 kms under different temparature conditions in last two days and the ACC performance has improved a lot. It now cools quickly than before. Also the ACC works better when outside tempartaure is lower than what I set on ACC. It is not fully satisfactory but still works in a way that I dont feel uncomfortable.

I checked with the Engineer who worked on this and he mentioned that he did found few issues with sensors and blower and it was fixed.

[S5157]

Dear All,

I am facing a strange issue with my 2.5 year old ( 58k kms done) Sx4's (petrol) automatic climate control. The issue is, the ac compressor switches off abruptly causing the cabin the heat up. The blower will continue to work. If we try to set the temperature to the blue zone( below 20c) the blower will increase the speed but compressor will not switch on. It starts working by its own after some time ( within 5-15 minutes). The following checks has been done by MASS so far

1. Check and Refill the AC refrigerant gas.

2. Connect the scanning equipment and check for any errors. There was an error related to sunload sensor which reads the info regarding the amount of sunlight from the sensor kept on the dashboard. But the technician mentioned that that is because the car was parked inside the service center. As per him no issues are observed.

3. I noticed that during the test, the scanning equipment showed 35C as external temperature but the external temperature read-out on the dashboard of sx4 was showing 30C.( Not sure if it is related to this issue).

4. While the issue happens if we try to switch off and switch on the AC we cant hear the click sound from the compressor.

Please share with me your experience and possible causes with similar issues which I could share with the technicians at MASS.

Thanks.

[dhanushs]

Originally Posted by S5157

If we try to set the temperature to the blue zone( below 20c) the blower will increase the speed but compressor will not switch on.

As the blower is increasing speed, I think the climate sensors are not at fault.

So, the compressor is not turning ON, and the problem should be in AC refrigerant leaking out, or compressor/clutch.

Did they check the latter?

[S5157]

Originally Posted by dhanushs

As the blower is increasing speed, I think the climate sensors are not at fault.

So, the compressor is not turning ON, and the problem should be in AC refrigerant leaking out, or compressor/clutch.

Did they check the latter?

Hello dhanushs,

Many thanks for your inputs.

They've checked the ac refrigerant. They vaccumed it and refilled again. However they have not checked the compressor physically. I will ask them to check that.

The strange thing is, the AC cools the cabin well when it works. Can AC cool efficiently if the refrigerant is leaking?

[vikram_d]

Originally Posted by dhanushs

So, the compressor is not turning ON, and the problem should be in AC refrigerant leaking out, or compressor/clutch.

Did they check the latter?

I agree with Dhanush. This sounds like a problem with the compressor clutch. Sound like it is not engaging properly at times. There is a electrical relay that supplies power to this clutch and such errors are not logged by any of the scanners. Please take a look at the relay also.

As far as difference between external temperatures is concerned, I wouldn't bother too much as these sensors are not very accurate.

Edit: Also since the compressor kicking in is sporadic, get all the electrical connections checked. Also check coolant levels. When the coolant changed last? Bad coolant causes the engine to overheat slightly and when this happens the ECU cuts out electrical load to help cool the engine.

Edit 2: If there is a refrigerant leak, the AC will not cool at all. Disclaimer: This depends on the amount of refrigerant present in the system. If the leak is a major one the refrigerant will leak out completely and there will be no cooling at all. If it is a slow leak then the cooling will go down gradually. I don't think your problem is being caused by refrigerant leak.

[S5157]

Originally Posted by vikram_d

I agree with Dhanush. This sounds like a problem with the compressor clutch. Sound like it is not engaging properly at times. There is a electrical relay that supplies power to this clutch and such errors are not logged by any of the scanners. Please take a look at the relay also.

As far as difference between external temperatures is concerned, I wouldn't bother too much as these sensors are not very accurate.

Edit: Also since the compressor kicking in is sporadic, get all the electrical connections checked. Also check coolant levels. When the coolant changed last? Bad coolant causes the engine to overheat slightly and when this happens the ECU cuts out electrical load to help cool the engine.

Edit 2: If there is a refrigerant leak, the AC will not cool at all. Disclaimer: This depends on the amount of refrigerant present in the system. If the leak is a major one the refrigerant will leak out completely and there will be no cooling at all. If it is a slow leak then the cooling will go down gradually. I don't think your problem is being caused by refrigerant leak.

Thank you Vikram_d.

The coolant was changed as part of regular service at 57K kms twenty days back. The coolant level was above the full level in reservoir and I asked them to drain it till FULL level mark while they were troubleshooting the AC issue yesterday. I checked the engine temperature gauge during the issue and it was at half mark. Also to mention that the AC comes back on after 10-15 minutes without turning the engine off. So I think Engine overheating can be ruled out. However You are correct about AC and engine overheating, I had this issue with My wagonr once it overheated due to a coolant leak and A/C shutdown was pointer which helped me notice the overheating.

I will ask MASS to check the relay/compressor clutch and electrical connections.

[latentpotential]

There is a temperature sensor in the ACC unit, which needs to be recalibrated. Since you are getting cooling, cutoff and on, this points to faulty calibration of the sensor. If this sensor was calibrated, you will see the notings on the job card related to initial detected value, difference noted, and final value set.

[S5157]

The car was with MASS for troubleshooting on Saturday 4th May. They suspect the thermistor which controls the compressor could be faulty. Unfortunatley the part was not in stock and has to be ordered. The car will be sent to MASS today for replacing the that unit.

[vikram_d]

Originally Posted by S5157

The car was with MASS for troubleshooting on Saturday 4th May. They suspect the thermistor which controls the compressor could be faulty. Unfortunatley the part was not in stock and has to be ordered. The car will be sent to MASS today for replacing the that unit.

Let us know if that solves the issue once the thermistor has been replaced.

[beast_within]

Sorry for bumping this thread. I have a query on the functioning of Auto AC in Maruti or any other car for that matter:

Case 1: Manual AC with mechanical temperature control knob.

As per my understanding, even if the temperature control knob is 1 notch less then the "Coldest" position some amount of hot air shall be mixed with the cold air by the HVAC system.

Case 2: Auto AC ( Digital temperature control knob)

Maruti's Auto AC has temperature ranging from LO, 18, 19......31, 32, HI.


My car has been parked under the Sun and the ambient temperature is 45 degrees. I set the ACC temperature to say 24 degrees in Auto Mode. Now the blower starts at Full Blast.

Now my query goes like this-

Since the temperature is not set to the lowest position ("Lo"), is ACC still mixing some amount of hot air and compensating this with full blower speed for a longer duration to bring down temperature inside the cabin?

Or the ACC logic is intelligent enough not to mix the hot air with cold air (although the temperature is not set to the lowest possible value). Since mixing of hot air is not required in this case and will only decrease cooling performance.

In other words I wish to know if the ratio of Cold:Hot air is hard coded into the ACC logic for very temperature value (Lo, 18, 19......31, 32, Hi) and only the fan speed is varied based on the inputs from various sensors.