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Hotline Archive: The Air Conditioning (A/C) compressor will not run
Having access to the biggest USA workshop live hotline databases, I will publish them here and might help some.
Customer Concern: The Air Conditioning (A/C) compressor will not run
Average Reported Mileage: 107618 Tests/Procedures:
1. Evacuate and recharge the Air Conditioning (A/C) system with the correct amount of refrigerant. Clear stored DTCs and recheck A/C operation.
2. Connect a scan tool to the climate control unit N22 and with system commanded to run the compressor, watch the percentage of command. With the compressor being commanded to run (scan tool showing a number like 70%) and while watching data on the pressure sensor, the system should show a pressure change.
3. With no change in pressure, connect the scan tool to the left front Signal Activation Module (SAM) N10/6. Perform activation of the compressor using the scan tool, while watching voltage output with a voltmeter at the compressor connector.
4. Perform a resistance check of the wiring from the A/C compressor to the left front SAM N10/6 connector 3 pin #10. Expect about 10 ohms from the solenoid in the compressor.
5. Verification of faulty parts requires activation of the compressor via a compatible scan tool. Tech Tips: Pressure sensor readings need to match the gauge set readings. Signal Activation Modules (SAM) need to be coded with a scan tool to operate correctly. B1640 The component or the signal line to the component A9 (AC compressor) has open circuit or short circuit.
42 - Replaced Air Conditioning (A/C) Compressor
23 - Cleared/Cleaned Heating Ventilation And Air Conditioning (HVAC) Codes
9 - Recharged Air Conditioning (A/C) Refrigerant
7 - Cleared Air Conditioning (A/C) System Low Refrigerant Codes
7 - Replaced/Coded/Cleared Left Front Signal Activation Module (SAM) N10/6
6 - Replaced/Cleared/Programmed/Coded Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
4 - Recharged Air Conditioning (A/C) Refrigerant and Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
3 - Replaced Refrigerant Pressure Sensor
2 - Cleared Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7 and Cleared Left Front Signal Activation Module (SAM) N10/6
2 - Replaced Fuse(s)
1 - Repaired Air Conditioning (A/C) Compressor Solenoid Wiring
1 - Information Only Air Conditioning (A/C) Refrigerant and Replaced Fuse(s)
1 - Replaced Signal Activation Module (SAM) N10/6
1 - Reset Climate Control Unit and Reset Left Front Signal Activation Module (SAM) N10/6
1 - Replaced Air Conditioning (A/C) Compressor and Replaced Rear Signal Activation Module (SAM) Control Unit
1 - Cleared Heating Ventilation And Air Conditioning (HVAC) Codes and Cleared Signal Activation Module (SAM) N10/6
1 - Recharged Air Conditioning (A/C) Refrigerant and Replaced Thermal Expansion Valve O-Rings
1 - Replaced A/C High Side Service Port and Cleaned Heating Ventilation And Air Conditioning (HVAC) Codes
1 - Recharged Air Conditioning (A/C) Refrigerant and Performed Air Conditioning System Evacuation Procedure
1 - Replaced Evaporator Temperature Switch
1 - Replaced Air Conditioning (A/C) Refrigerant and Cleared Air Conditioning (A/C) System Low Refrigerant Codes
1 - Replaced Air Conditioner Relay
1 - Replaced Thermal Expansion Valve O-Rings
October 3, 2015 2004 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Compressor
- Clutch was melting due to failed bearing, freon began to leak from front seal. Replaced compressor, drier, tensioner and belt. Reset control panel.
Replaced Air Conditioning (A/C) Compressor
November 11, 2016 2003 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Compressor
- run codes through the actual ac controls and then reset codes and goes back to normal opereation.....
Replaced Air Conditioning (A/C) Compressor
February 18, 2019 2002 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Compressor
- reprogram ac module after repair .. clear codes reprogram so compressor will come on
Replaced Air Conditioning (A/C) Compressor
February 4, 2019 2001 Mercedes-Benz S600, 5.8L, V12, USA *
Air Conditioning (A/C) Compressor
- cleared codes in a/c control head.scanner wont show any codes in a/c module
Replaced Air Conditioning (A/C) Compressor
March 18, 2018 2003 Mercedes-Benz SL500, 5.0L, V8, MFI, USA *
Air Conditioning (A/C) Compressor
- AC compressor had leaked out refrigerant - it was soaked in UV oil.
Replaced Air Conditioning (A/C) Compressor
May 1, 2015 2003 Mercedes-Benz SL500, 5.0L, V8, MFI, USA *
Air Conditioning (A/C) Compressor
- found low system pressure.module shutting off compressor
Replaced Air Conditioning (A/C) Compressor
April 30, 2015 2005 Mercedes-Benz S430, 4Matic 4.3L, V8, Des 113.948, USA *
Air Conditioning (A/C) Compressor
- Pulley was spinning but the shaft was not.
Replaced Air Conditioning (A/C) Compressor
March 27, 2018 2003 Mercedes-Benz S430, 4.3L, V8, Des 113.941, USA *
Air Conditioning (A/C) Compressor
- have to to clear codes in ac control unit
Replaced Air Conditioning (A/C) Compressor
July 6, 2011 2002 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) Compressor
- AIR CONDITIONING COMPRESSOR
Replaced Air Conditioning (A/C) Compressor
April 12, 2011 2001 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) Compressor
- replaced a/c compressor
Replaced Air Conditioning (A/C) Compressor
July 14, 2017 2004 Mercedes-Benz SL500, 5.0L, V8, MFI, USA
Heating Ventilation And Air Conditioning (HVAC) Codes Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
May 17, 2014 2002 Mercedes-Benz S600, 5.8L, V12, MFI, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes
- had no a/c operation checked for codes found 3 history codes. b1269 b1424 b1298 cleared codes a/c works and codes have not returned.
Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
October 1, 2015 2002 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes
- snapon scanner with latest update would not do a/c module, thanks to not getting rid of my autel was able to clear low refig code.
Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
March 19, 2018 2004 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes
- cleared codes from climate module then ac would function. ac off button was illuminated.
Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
January 17, 2019 2004 Mercedes-Benz S500, 4Matic 5.0L, V8, Des 113.966, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes
- HAD TO ACCESS CODE MENU THROUGH HVAC DISPLAY AND CLEAR CODES
Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
June 26, 2013 2003 Mercedes-Benz S430, 4Matic 4.3L, V8, Des 113.948, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes
- Manually acquired codes and cleared.
Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
March 6, 2012 2004 Mercedes-Benz S600, 5.5L, V12, MFI, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes
- Cleared codes in ac module
Cleaned Heating Ventilation And Air Conditioning (HVAC) Codes
August 2, 2018 2004 Mercedes-Benz S600, 5.5L, V12, MFI, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
July 29, 2018 2003 Mercedes-Benz S500, 4Matic 5.0L, V8, Des 113.966, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
July 28, 2018 2001 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
May 26, 2010 2000 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) Refrigerant
- customer compaint was no cold air. a/c recharge and clear codes with scan tool fixed car
Recharged Air Conditioning (A/C) Refrigerant
December 4, 2012 2005 Mercedes-Benz S600, 5.5L, V12, MFI, USA *
Air Conditioning (A/C) Refrigerant
- PROPERLY CHARGED A/C SYSTEEM
Recharged Air Conditioning (A/C) Refrigerant
June 18, 2013 2000 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Refrigerant
- LOW ON FREON
Recharged Air Conditioning (A/C) Refrigerant
June 1, 2013 2000 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) Refrigerant
- ac serivce
Recharged Air Conditioning (A/C) Refrigerant
October 29, 2019 2006 Mercedes-Benz S600, 5.5L, V12, MFI, USA *
Air Conditioning (A/C) Refrigerant Recharged Air Conditioning (A/C) Refrigerant
July 11, 2019 2001 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Refrigerant Recharged Air Conditioning (A/C) Refrigerant
April 30, 2019 2002 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) Refrigerant Recharged Air Conditioning (A/C) Refrigerant
April 18, 2017 2002 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Refrigerant Recharged Air Conditioning (A/C) Refrigerant
May 18, 2016 2004 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) Refrigerant Recharged Air Conditioning (A/C) Refrigerant
July 9, 2015 2005 Mercedes-Benz S430, 4Matic 4.3L, V8, Des 113.948, USA *
Air Conditioning (A/C) System Low Refrigerant Codes
- HAD TO USE STAR DIAGNOSIS TOOL TO ACCESS THE HVAC SYSTEM, SNAP ON VERUS DID NOT HAVE THE ABILITY TO DO SO
Cleared Air Conditioning (A/C) System Low Refrigerant Codes
June 23, 2018 2002 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) System Low Refrigerant Codes Cleared Air Conditioning (A/C) System Low Refrigerant Codes
September 2, 2017 2001 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) System Low Refrigerant Codes Cleared Air Conditioning (A/C) System Low Refrigerant Codes
May 21, 2016 2004 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) System Low Refrigerant Codes Cleared Air Conditioning (A/C) System Low Refrigerant Codes
October 10, 2015 2000 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioning (A/C) System Low Refrigerant Codes Cleared Air Conditioning (A/C) System Low Refrigerant Codes
July 26, 2015 2002 Mercedes-Benz SL500, 5.0L, V8, Des 113.961, USA *
Air Conditioning (A/C) System Low Refrigerant Codes Cleared Air Conditioning (A/C) System Low Refrigerant Codes
July 1, 2015 2005 Mercedes-Benz SL500, 5.0L, V8, MFI, USA *
Air Conditioning (A/C) System Low Refrigerant Codes Cleared Air Conditioning (A/C) System Low Refrigerant Codes
July 27, 2016 2003 Mercedes-Benz SL500, 5.0L, V8, MFI, USA *
Left Front Signal Activation Module (SAM) N10/6
- THE AC COMPUTER SHOWED 70% DUTY CYCLE. BUT THE SAM PIN 10 OF THE SECOND CONNECTOR (MIDDLE) W GREEN AND BLUE WIRE HAD 0 VOLTS OUTPUT. ALSO, LEFT FRONT MARKER LIGHT BULB STAYED ON AND LEFT HEAD LIGHT BULB HAD EXPLODED (INDICATING A SHORT, WITCH WAS A SAM MOD. INTERNAL PROBLEM)
Replaced Left Front Signal Activation Module (SAM) N10/6
July 9, 2016 2000 Mercedes-Benz S500, Guard 5.0L, V8, Des 113.960, USA *
Left Front Signal Activation Module (SAM) N10/6
Left Front Signal Activation Module (SAM) N10/6
102,000 miles Coded Left Front Signal Activation Module (SAM) N10/6
July 9, 2016 2002 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Left Front Signal Activation Module (SAM) N10/6
- Tech found no 5 V supply to the sensor, no right headlight operation, no temperature display on cluster, parking/fluid level light is on, wipers inop, steering tilt inop. All parts that are controlled by the left front Signal Activation Module (SAM). Further inspection found corrosion in the SAM.
69,435 miles Replaced Left Front Signal Activation Module (SAM) N10/6
July 9, 2016 2002 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Left Front Signal Activation Module (SAM) N10/6
28,000 miles Replaced Left Front Signal Activation Module (SAM) N10/6
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July 9, 2016 2003 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Left Front Signal Activation Module (SAM) N10/6
50,662 miles Cleared Left Front Signal Activation Module (SAM) N10/6
July 3, 2016 2002 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Left Front Signal Activation Module (SAM) N10/6
- Cleared fault codes in the N10/6 to get the compressor to operate.
141,821 miles Cleared Left Front Signal Activation Module (SAM) N10/6
July 3, 2016 2000 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Left Front Signal Activation Module (SAM) N10/6
115,000 miles Replaced Left Front Signal Activation Module (SAM) N10/6
February 12, 2019 2002 Mercedes-Benz CL500, 5.0L, V8, Des 113.960, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7 Replaced Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
March 31, 2017 2002 Mercedes-Benz ML55 AMG, 5.5L, V8, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
68,771 miles Replaced Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
July 9, 2016 2001 Mercedes-Benz S600, 5.8L, V12, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
85,078 miles Replaced Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
July 9, 2016 2006 Mercedes-Benz CL500, 5.0L, V8, Des 113.960, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
32,856 miles Cleared Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
July 9, 2016 2004 Mercedes-Benz CL500, 5.0L, V8, Des 113.960, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
66,623 miles Programmed Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
July 3, 2016 2002 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
- A fully functional Mercedes-Benz compatible scan tool was used to normalize and recode the AC control module.
94,221 miles Coded Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
May 31, 2015 2003 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Refrigerant
Heating Ventilation And Air Conditioning (HVAC) Codes
- recharge and cleared codes customer declined further diagnostics
Recharged Air Conditioning (A/C) Refrigerant and Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
July 27, 2013 2003 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Refrigerant
Heating Ventilation And Air Conditioning (HVAC) Codes
- Clear low refrigerant codes and charge ac system
Recharged Air Conditioning (A/C) Refrigerant and Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
April 26, 2012 2001 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Refrigerant
Heating Ventilation And Air Conditioning (HVAC) Codes
- charge system and reset codes a/c module
Recharged Air Conditioning (A/C) Refrigerant and Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
June 8, 2013 2004 Mercedes-Benz S600, 5.5L, V12, MFI, USA *
Air Conditioning (A/C) Refrigerant
Heating Ventilation And Air Conditioning (HVAC) Codes
- cleared dtcs and recharged system
Recharged Air Conditioning (A/C) Refrigerant and Cleared Heating Ventilation And Air Conditioning (HVAC) Codes
June 22, 2018 2002 Mercedes-Benz CL55 AMG, 5.5L, V8, USA *
Refrigerant Pressure Sensor Replaced Refrigerant Pressure Sensor
July 9, 2016 2003 Mercedes-Benz S430, 4.3L, V8, Des 113.941, USA *
Refrigerant Pressure Sensor
45,000 miles Replaced Refrigerant Pressure Sensor
July 3, 2016 2001 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Refrigerant Pressure Sensor
- Sensor was not reading correct system pressures.
78,000 miles Replaced Refrigerant Pressure Sensor
July 9, 2016 2005 Mercedes-Benz S430, 4Matic 4.3L, V8, Des 113.948, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
Left Front Signal Activation Module (SAM) N10/6
99,000 miles Cleared Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7 and Cleared Left Front Signal Activation Module (SAM) N10/6
July 9, 2016 2006 Mercedes-Benz S430, 4Matic 4.3L, V8, Des 113.948, USA *
Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7
- Cleared codes.
Left Front Signal Activation Module (SAM) N10/6
- Cleared codes.
112,000 miles Cleared Comfort Automatic Air Conditioning (C-AAC) Control Module N22/7 and Cleared Left Front Signal Activation Module (SAM) N10/6
January 27, 2019 1998 Mercedes-Benz CL500, 5.0L, V8, MFI, USA *
Fuse(s) Replaced Fuse(s)
June 29, 2015 2003 Mercedes-Benz S500, 4Matic 5.0L, V8, Des 113.966, USA *
Fuse(s) Replaced Fuse(s)
November 8, 2015 2003 Mercedes-Benz S430, 4.3L, V8, Des 113.941, USA *
A/C High Side Service Port
Heating Ventilation And Air Conditioning (HVAC) Codes
- low on refrigerant. replace leaking service ports and clear codes in control unit.
Replaced A/C High Side Service Port and Cleaned Heating Ventilation And Air Conditioning (HVAC) Codes
September 10, 2015 2000 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Air Conditioner Relay Replaced Air Conditioner Relay
May 31, 2016 2003 Mercedes-Benz S430, 4.3L, V8, Des 113.941, USA *
Air Conditioning (A/C) Compressor Solenoid Wiring
196,444 miles Repaired Air Conditioning (A/C) Compressor Solenoid Wiring
July 9, 2016 2002 Mercedes-Benz S500, 5.0L, V8, Des 113.960, USA *
Air Conditioning (A/C) Compressor
Rear Signal Activation Module (SAM) Control Unit
102,000 miles Replaced Air Conditioning (A/C) Compressor and Replaced Rear Signal Activation Module (SAM) Control Unit
August 11, 2015 2003 Mercedes-Benz S500, 4Matic 5.0L, V8, Des 113.966, USA *
Air Conditioning (A/C) Refrigerant
Air Conditioning (A/C) System Low Refrigerant Codes
- Recharged ac/ added leak detection dye, cleared codes, ac good at this time, need to recheck vehicle for leak.
Replaced Air Conditioning (A/C) Refrigerant and Cleared Air Conditioning (A/C) System Low Refrigerant Codes
May 2, 2013 2002 Mercedes-Benz E55 AMG, 5.5L, V8, USA *
Air Conditioning (A/C) Refrigerant
Air Conditioning System Evacuation Procedure
- low freon. a/c off light always on. ecavuated and recharged a/c/system. cleared codes< even though there are no codes in the system>. rechecked system operation. pass.
Recharged Air Conditioning (A/C) Refrigerant and Performed Air Conditioning System Evacuation Procedure
September 13, 2019 2001 Mercedes-Benz S600, 5.8L, V12, USA *
Air Conditioning (A/C) Refrigerant
Fuse(s)
- replaced fuse, recharged system
Information Only Air Conditioning (A/C) Refrigerant and Replaced Fuse(s)
October 10, 2015 2000 Mercedes-Benz E55 AMG, 5.5L, V8, MFI, USA *
Air Conditioning (A/C) Refrigerant
Thermal Expansion Valve O-Rings
- Evacuated and recharged system. Compressor functions normally. Located leak at expansion valve seals Resealed.
Recharged Air Conditioning (A/C) Refrigerant and Replaced Thermal Expansion Valve O-Rings
July 9, 2016 2004 Mercedes-Benz S430, 4.3L, V8, MFI, USA *
Climate Control Unit
- Cleared fault codes with scan tool.
Left Front Signal Activation Module (SAM) N10/6
- Cleared fault codes with scan tool.
110,352 miles Reset Climate Control Unit and Reset Left Front Signal Activation Module (SAM) N10/6
August 3, 2016 2000 Mercedes-Benz CL500, 5.0L, V8, USA *
Evaporator Temperature Switch Replaced Evaporator Temperature Switch
July 9, 2016 2000 Mercedes-Benz S500, Guard 5.0L, V8, Des 113.960, USA *
Heating Ventilation And Air Conditioning (HVAC) Codes
Signal Activation Module (SAM) N10/6 Cleared Heating Ventilation And Air Conditioning (HVAC) Codes and Cleared Signal Activation Module (SAM) N10/6
April 25, 2018 2003 Mercedes-Benz SL500, 5.0L, V8, MFI, USA *
Signal Activation Module (SAM) N10/6
- For months had issue with this car killing battery over night and finnaly compressor stop working replaced left front sam module and took care of all issues
Replaced Signal Activation Module (SAM) N10/6
October 10, 2015 2000 Mercedes-Benz ML55 AMG, 5.5L, V8, USA *
Thermal Expansion Valve O-Rings
- REPLACED EXPANSION VALVE SEALS
Since the operation of the climate control in the R239 us well-doicyumented and widely-understood, I was taken aback by the number of errors in the prior post.
Originally Posted by pmercury
Customer Concern: The Air Conditioning (A/C) compressor will not run
The R230 has a variable- displacement-type compressor which has no clutch and always runs.
Originally Posted by pmercury
Tests/Procedures:
1. Evacuate and recharge the Air Conditioning (A/C) system with the correct amount of refrigerant. Clear stored DTCs and recheck A/C operation.
This is not a test procedure. It is a repair procedure which is performed if a component of the refrigerant circuit has been replaced or the wrong refrigerant is installed.
Originally Posted by pmercury
3. With no change in pressure, connect the scan tool to the left front Signal Activation Module (SAM) N10/6. Perform activation of the compressor using the scan tool, while watching voltage output with a voltmeter at the compressor connector.
The left-front SAM is designated N10/10. There is no such component as N10/6.
Some scan tools such as the iCarsoft i980 lack the ability to perform actuations such as the compressor control signal described here. Fortunately this is entirely unnecessary, as setting temperature controls on the in-dash control unit can accomplish the very same thing.
Originally Posted by pmercury
4. Perform a resistance check of the wiring from the A/C compressor to the left front SAM N10/6 connector 3 pin #10. Expect about 10 ohms from the solenoid in the compressor.
There is no solenoid in this circuit, and the resistance should be orders of magnitude greater than 10 ohms. Perhaps you are thinking a clutch is involved?
Originally Posted by pmercury
.
5. Verification of faulty parts requires activation of the compressor via a compatible scan tool,
For reasons explained before this is completely untrue.
@pmercury - I appreciate you compiling this data. I have a R171.456 in which the A/C has always worked properly until once it stopped cooling completely. Icy cold one time driving and the next no compressor operation at all. I have Star and while it shows 100% compressor call from climate controller N22/7, the compressor is only drawing a few millivolts. The high and low refirgerant pressures do not change and the evaporator does not show a drop in temp. The statIc refrigerant pressure suggest the system has refrigerant in it. No fault codes.
Without the engine running so that I can hear, I have put a brief 5 volts to the power side of the compressor to see if it will energize. I can clearly hear clicking from the solenoid as I apply and remove the power.
In your first post the list includes - Reset Climate Control Unit and Reset Left Front Signal Activation Module (SAM) N10/6 I have not found a reset function in Star for either the climate controller or the front SAM. Can you point to me where those Reset functions are located? I really appreciate it.
05-21-2020, 05:23 PM
Hotline Archive: The Air Conditioning (A/C) compressor will not run
