Go Back   Team-BHP > Under the Hood > Technical Stuff


Reply
 
Thread Tools Search this Thread
Old 8th March 2012, 12:38   #1
BHPian
 
revved_up's Avatar
 
Join Date: Jul 2007
Location: New Delhi
Posts: 689
Thanked: 210 Times
Unhappy AC tripping when the car is at a standstill

Hi All,

I own a Swift Vdi (May 2008) model, the car has done 73k and i got the last service done at 69.5K where all the fluid as per the manual were replaced.

This week i noticed that the AC of the car trips whenever the car is standing still. Once the car starts moving and is in motion for about 2 secs or so, the AC starts cooling again.
All this time the AC button is on and the light for it is also glowing. While the car is standing still, I noticed that there is no change in rpm as well if i turn off and on the ac.

I plan to take the car to Maruti Nariana on saturday, just wanted to take forum's advice here.

Any pointers, or is it some type of blue motion that has got enabled on my car .

Please advise.

Thanks in advance.
revved_up is offline   Reply With Quote
Old 8th March 2012, 12:41   #2
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: AC tripping while car is standstill

First and foremost is to check battery and alternator health. If the voltage is dropping below a certain level the ECU will start cutting out overheads.
vikram_d is offline   (4) Thanks Reply With Quote
Old 8th March 2012, 12:45   #3
Newbie
 
Join Date: Apr 2011
Location: Delhi
Posts: 1
Thanked: Once
Default

Looks like time to recharge your Ac gas. These are signs of less quantity of Ac gas.
tashan4*4 is offline   (1) Thanks Reply With Quote
Old 8th March 2012, 13:03   #4
BHPian
 
revved_up's Avatar
 
Join Date: Jul 2007
Location: New Delhi
Posts: 689
Thanked: 210 Times
Default Re: AC tripping while car is standstill

Battery was changed with an Amaron one last year. I dont think its the battery, so the alternator, will get them checked.


Quote:
Originally Posted by tashan4*4 View Post
Looks like time to recharge your Ac gas. These are signs of less quantity of Ac gas.
If it was the gas, wouldnt i notice drop in cooling once the AC is running?

Last edited by revved_up : 8th March 2012 at 13:06.
revved_up is offline   Reply With Quote
Old 8th March 2012, 13:16   #5
gpa
Senior - BHPian
 
gpa's Avatar
 
Join Date: Aug 2008
Location: Bangalore
Posts: 1,772
Thanked: 273 Times
Default Re: AC tripping while car is standstill

As vikram_d has said, this could be due to the low voltage being generated by the alternator. The battery might be new, but since the alternator is putting out such low voltage, the ECU is forcing the a/c to trip when the engine is at idle.

If you have a multi-meter you can hook it up and check the output voltage of the alternator with the engine at idle. It should read ~14.5 volts at idle IIRC.
gpa is online now   (1) Thanks Reply With Quote
Old 8th March 2012, 13:48   #6
BHPian
 
revved_up's Avatar
 
Join Date: Jul 2007
Location: New Delhi
Posts: 689
Thanked: 210 Times
Default Re: AC tripping while car is standstill

Just did a quick search.. and looks like the alternator is quite costly, somewhere around 15k.

If it turns out to be the alternator, is replacement the only option or can it be repaired as well.

FYI, my vehicle is out of warranty now.
revved_up is offline   Reply With Quote
Old 8th March 2012, 14:49   #7
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: AC tripping while car is standstill

Quote:
Originally Posted by revved_up View Post
If it was the gas, wouldnt i notice drop in cooling once the AC is running?
What Tashan has said may also be true. In this scenario you will notice a drop in AC cooling at idling but not while moving because while the car is moving in gear the AC compressor will be running at a higher RPM and hence cooling will be better.

Point to note is that if the gas is low then that means there is a leak in the AC system and you will need to trace the leak and rectify it before getting the gas refilled.

Quote:
Originally Posted by revved_up View Post
If it turns out to be the alternator, is replacement the only option or can it be repaired as well.
The alternator can be easily repaired though the M.A.S.S will recommend replacement as that is the company specified policy.

Also if you have a multimeter you can check to see the charging voltage. While the car is idling with full electrical load connect your multimeter to the battery terminals and it should read between 13.4 - 14.5 volts DC.

Last edited by vikram_d : 8th March 2012 at 14:50.
vikram_d is offline   (3) Thanks Reply With Quote
Old 8th March 2012, 15:36   #8
Senior - BHPian
 
mayankjha1806's Avatar
 
Join Date: Jan 2011
Location: BLR/Gurgaon
Posts: 2,133
Thanked: 820 Times
Default Re: AC tripping while car is standstill

The other area, (not mentioned in the above posts) worth checking, is the car overheating.

I have seen this problem (Not in my current set of cars) in the past when the car was overheating the AC would be cut off to decrease the load on the engine and when the car starts moving the engine cools down with the air flow from the radiator and the AC starts to function again.
mayankjha1806 is offline   (1) Thanks Reply With Quote
Old 8th March 2012, 15:55   #9
BHPian
 
Blow Horn Ok's Avatar
 
Join Date: Feb 2012
Location: Bokaro
Posts: 597
Thanked: 359 Times
Default Re: AC tripping while car is standstill

If the alternator is at fault, You can get the alternator checked at the service center of the alternator brand. It may be of Lucas or Bosch. There are several authorized car electrical repair shops of these brands. Even the MASS guys will send it to the nearest authorized repairing shop. The alternator can be very well repaired. Get the alternator belt tension checked.
Blow Horn Ok is offline   (1) Thanks Reply With Quote
Old 8th March 2012, 20:05   #10
BHPian
 
revved_up's Avatar
 
Join Date: Jul 2007
Location: New Delhi
Posts: 689
Thanked: 210 Times
Default Re: AC tripping while car is standstill

Quote:
Originally Posted by vikram_d View Post
What Tashan has said may also be true. In this scenario you will notice a drop in AC cooling at idling but not while moving because while the car is moving in gear the AC compressor will be running at a higher RPM and hence cooling will be better.

Point to note is that if the gas is low then that means there is a leak in the AC system and you will need to trace the leak and rectify it before getting the gas refilled.



The alternator can be easily repaired though the M.A.S.S will recommend replacement as that is the company specified policy.

Also if you have a multimeter you can check to see the charging voltage. While the car is idling with full electrical load connect your multimeter to the battery terminals and it should read between 13.4 - 14.5 volts DC.
Hi Vikram,

Just checked the alternator with with multimeter and below are the readings:

- Cold battery(car not started for about 6-7 hours) - 12.6
- Car started with no load - 14.10
- Car started with full load(headlights on and ac on) - 14.10
- Car turned off now - 13.5

From the abve readings looks like the alternator is not at fault..correct?

Also another thing i would like to point out, when the ac trips while the car is diling, the rpm needle also drops a little.

Does the rpm needle dropping not indicate that it is tripping and not some gas leakage issue in which the compressor would have continued to run with no cooling?
Another thing that i noticed that, when i do a cold start, the ac runs for some time (say about a minute or two), then eventually it trips.

Please advise. Thanks again for all your help.

Last edited by revved_up : 8th March 2012 at 20:07.
revved_up is offline   Reply With Quote
Old 8th March 2012, 20:09   #11
BHPian
 
Catalyst_delhi's Avatar
 
Join Date: Oct 2011
Location: Noida/Coimbator
Posts: 339
Thanked: 148 Times
Default Re: AC tripping while car is standstill

Quote:
Originally Posted by revved_up View Post
Hi Vikram,

Just checked the alternator with with multimeter and below are the readings:

- Cold battery(car not started for about 6-7 hours) - 12.6
- Car started with no load - 14.10
- Car started with full load(headlights on and ac on) - 14.10
- Car turned off now - 13.5

From the abve readings looks like the alternator is not at fault..correct?

Also another thing i would like to point out, when the ac trips while the car is diling, the rpm needle also drops a little.

Does the rpm needle dropping not indicate that it is tripping and not some gas leakage issue in which the compressor would have continued to run with no cooling?

Please advise. Thanks again for all your help.
I have seen this before in an ikon , it is loose wires near the fuse box and grounding issues. Check the circuit from the switch to relay to compressor. Also check AC pressure switch and low speed / Ac fan is working good. Your alternator readings looks fine. I am almost sure it is the fan though. can you check if the AC works if you stand still with the engine on a mild rev
(1800rpm)

Last edited by Catalyst_delhi : 8th March 2012 at 20:15. Reason: more info
Catalyst_delhi is offline   Reply With Quote
Old 8th March 2012, 20:12   #12
BHPian
 
Blow Horn Ok's Avatar
 
Join Date: Feb 2012
Location: Bokaro
Posts: 597
Thanked: 359 Times
Default Re: AC tripping when the car is at a standstill

Ideally starting the AC at idling should increase the rev. Its done to counter the extra load on the engine and prevent it from stalling. Visit the A.S.S.C and let them inspect. You may also get an opinion from a reputed garage outside before taking it to A.S.S.C. Since you have done considerable amount of running, the AC might require some maintenance.

Last edited by Blow Horn Ok : 8th March 2012 at 20:14.
Blow Horn Ok is offline   Reply With Quote
Old 8th March 2012, 23:46   #13
Team-BHP Support
 
Zappo's Avatar
 
Join Date: Oct 2005
Location: Hyderabad
Posts: 5,653
Thanked: 2,013 Times
Default Re: AC tripping when the car is at a standstill

Sounds to me like a problem with the ISC. Different vehicles have similar device with different names (FICD, VSV) but they mostly control the idling speed of the car using a vaccuum pipe to ensure that minimum engine RPM necessary to run accessories like AC is available. Take the car to a workshop and get it checked for this problem. A temporary solution till then is to increase the idling RPM to around 900. That should ensure that your AC keeps running even when you stop at a traffic light. However get it rectified at the earliest since high idle RPM = low FE.
Zappo is offline   (1) Thanks Reply With Quote
Old 9th March 2012, 00:17   #14
Distinguished - BHPian
 
dhanushs's Avatar
 
Join Date: Oct 2009
Location: Bathery/BLR
Posts: 3,446
Thanked: 4,057 Times
Default Re: AC tripping while car is standstill

Quote:
Originally Posted by Catalyst_delhi View Post
I have seen this before in an ikon
Hi Catalyst delhi,

In an you are right, but actually, this can also happen due to loss of fluid pressure.

revved_up: I think: The issue is due to lack of fluid pressure. In this case, with low refrigerant fluid, the condenser is not able to make the necessary heat transfer. I had experienced this in my car.

Even with low refrigerant, while the vehicle is moving, ram air is sufficient to cool the cabin. Please check for AC gas pressure, and for leaks.

Thanks,

Dhanush
dhanushs is offline   (1) Thanks Reply With Quote
Old 9th March 2012, 00:30   #15
BHPian
 
kbalii's Avatar
 
Join Date: Nov 2008
Location: Chennai
Posts: 102
Thanked: 21 Times
Default Re: AC tripping while car is standstill

Quote:
Originally Posted by revved_up View Post
Hi Vikram,

Just checked the alternator with with multimeter and below are the readings:

- Cold battery(car not started for about 6-7 hours) - 12.6
- Car started with no load - 14.10
- Car started with full load(headlights on and ac on) - 14.10
- Car turned off now - 13.5

From the abve readings looks like the alternator is not at fault..correct?

Also another thing i would like to point out, when the ac trips while the car is diling, the rpm needle also drops a little.

Does the rpm needle dropping not indicate that it is tripping and not some gas leakage issue in which the compressor would have continued to run with no cooling?
Another thing that i noticed that, when i do a cold start, the ac runs for some time (say about a minute or two), then eventually it trips.

Please advise. Thanks again for all your help.
You are right. The alternator is not at fault and that is a long shot after all.

The compressor for the AC comes with a coil / clutch / pullley. It is usually the round thingy, next to the compressor. Please check the round thingy checked, preferably somebody who knows the AC department well.
kbalii is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Sound from front wheels while turning the steering at standstill narasimha raju Technical Stuff 17 12th December 2014 00:55
The Dark Knight goes Temple Tripping KRRaj Travelogues 41 24th August 2010 21:49
Day Tripping in Mysore - Suggestion for What to do and where to stay Red Liner Route / Travel Queries 21 7th May 2009 12:04
AMP tripping namic In-Car Entertainment 4 26th March 2008 13:29
JBL 75.4 tripping over a GTO1204 sub amitverma In-Car Entertainment 22 8th September 2006 21:49


All times are GMT +5.5. The time now is 11:34.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks