Question about AC Cars & Trucks

2 Answers

Air compressor cycles when AC is off - AC Cars & Trucks

Posted by Robert Wagner on

Ad

2 Answers

CJ Withers

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Sergeant:

    An expert that has over 500 points.

  • Expert
  • 188 Answers

Depending on what year you have, a lot of vehicles made after 2000 will run the act compressor while in defrost. Doing so will dry the air before it hits your windows, clearing them of fog better/ faster. If your ac compressor runs in defrost, even when the a/c switch is off, that is normal. Try moving the selector to floor or face, if the compressor runs then with the switch off, there is a problem.

Posted on Feb 28, 2017

Ad

Thomas Perkins

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • AC Master
  • 14,912 Answers

May be a bad switch.

Posted on Feb 28, 2017

Ad

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
1answer

When air conditioner is on, and the car is idling the rpms spike

You most likely have an AC compressor that is cycling on and off to often, this causes the RPMs at idle to fluctuate. The rapid cycling of the AC compressor is caused by a low AC system charge of refrigerant due to a leak in most likely the compressor shaft seal. Please have an AC repair ship confirm this educated guess..
0helpful
1answer

Ac compressor cycles on and off to frequent

diagnose ac in ford is difficult process: however go to this page and read how to fix: God bless you

http://www.ehow.com/way_5444654_ford-air-conditioner-problems.html
1helpful
1answer

Clicking noise when the car is idling and AC is on. Now there is no cold air only hot air when the AC is on

This most likely is a symptom of low coolant presure. There is a pressure sensor both in the compressor and near the drier / expansion tank on the right side of the radiator. If either one of these senses low pressure the AC compressor clutch is disengaged. The clicking your hearing at idle is probably the compressor clutch cycling. You can watch it cycle by watching the front of the AC compressor pulley. Your watching for the center part to turn when AC is on and not turn when AC is off. Usually this is controlled by a temp sensor but if there is low pressure the preure switches will cause the compressor to cycle. Here is the kicker... you can pay to have the system serviced but.... if they pump it into a vacuum and it won't hold a vacuum there is a pin hole some where in the system usualy the evaporator coils inside the front passenger compartment. No one will re-service the coolant system with a system leak. It is against the law in most states.

Thanks for choosing FixYa,
Kelly
0helpful
1answer

I have a 02 lincoln ls . the air conditiong is not working . i took it to a local shop they check the compressor, fuses, relays, pressure swithches, all is checcking out good. They jump the compressor...

YOU COULD HAVE OPEN OR SHORT IN THE BLACK YELLOW WIRE GOING TO AC COMPRESSOR CYCLING PRESSURE SWITCH. CHECK FOR A SHORT OR OPEN IN RED YELLOW WIRES AT THE AC PRESSURE CUTOFF SWITCH. USE VOLT METER AND CHECK FOR VOLTAGE AT BOTH SWITCHES. PROBLEM COULD BE IN THE EATC MODULE THAT SEND POWER TO PURPLE WIRE THAT FEEDS THE AC PRESSURE CUTOFF SWITCH AND AC CLUTCH CYCLING PRESSURE SWITCH THEN FEEDS THE AC COMPRESSOR CLUTCH SOLENOID.
0helpful
1answer

My 2002 Expedition air conditioner will sometimes blow hot air and others cold air

I would check the following possibilities:
1. Is compressor clutch working? - You need to do this when the ac is blowing hot air only - locate compressor drive pulley on engine - rubber belt wraps around it. Start engine and set to max ac. When the ac is blowing hot air, look at the center of the compressor drive pulley using a good flash light - watch it for a while, it should be spinning with the pulley - this means the compressor is engaged. If not, the compressor is not engaged. If your ac is blowing hot air, then the compressor should be engaged and running (trying to cool). If it is not engaged, then your compressor clutch is probably going out. Could be low voltage to clutch, but more likely the clutch is worn out and only working some of the time. Note: if working normally, the compressor clutch will engage and disengage in cycles- but the air should always be cold. If clutch is bad, compressor would need to be replaced (sold as one unit). This is tricky to diagnose and could take some time - you need to do it when ac is blowing hot air but set to max cooling.

2. Low on refrigerant or refrigerant has moisture in it? If your ac blows cold initially after being off for a while, then heats up, and continues to regularly cycle back and forth between hot and cool air, then the system may be low on refrigerant or the refrigerant may have moisture in it that is freezing and restricting refrigerant flow. An a/c shop can check refrigerant level and even replace refrigerant if moisture is suspected.

Could be other issues, but I would start with these.

Good luck
1helpful
1answer

1998 VW Beetle AC cycling on and off

**** in the venturi valve ,remove the ac interior unit and clean it all out ,broken bits of the old compressor blocking the restrictor (venturi )
0helpful
1answer

AC still blows hot air

CYCLING COMPRESSOR COULD MEAN TOO MUCH OR TOO LITTLE FREON.TAKE IT TO AN A/C SHOP
1helpful
1answer

Idle Revs With Front Defrost

when you use the front defrost in the winter the cycling of tha a/c compressor will cause this condition.

when you use defrost the a/c is run to de-humidfy the air that is blown onto your windshield.


in the summer this is not a big deal as it is hot enough outside to keep the a/c system pressure above the compressor clutch cycle threshold. but in the winter the general lack of heat in the ambient air and the lack of humidity results in rapid cycling of the ac compressor.

the idle is bumped up to compensate for the load of the a/c compressor, or else your engine would stall out. but when the compressor is disengaged the idle is dropped. but it raises again when the compressor cycles back on.

there may be a good chance that your ac is under charged after all these years. when the weather gets warmer have the charge level in your ac system checked.

a low charge will also increase the on off on off cycling of the ac compressor, usually resulting in the complaint that you have. so the base issue of your problem is low ac system charge.
0helpful
1answer

AC compressor has short cycle. Constant on/off every 2 seconds.

have you checked the compressor oil it may be seizing up
Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

37 views

Ask a Question

Usually answered in minutes!

Top AC Experts

Pierre Laplante

Level 3 Expert

2061 Answers

David Harrelson
David Harrelson

Level 3 Expert

5456 Answers

old marine
old marine

Level 3 Expert

2366 Answers

Are you an AC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...