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Hi. I have a 2015 Mercedes C300 W205 with <50k mileage. My AC was working great until a few weeks ago when it suddenly started blowing warm air. There isn't any cold air coming out of it at all. I would really appreciate your help since I am in Florida and the car is not usable without the AC. l've been to two mechanics and they could not tell exactly what's wrong but wanted to check for leaks, then replace compressor, lines and valves, then replace other things if that wouldn't help. So really just taking guesses.
The heating works fine, the air is getting warmer when I turn the temperature up.
The fan behind the radiator is being engaged
The compressor starts spinning when I turn on AC and stops when I turn it off.
I checked the AC pressure and the low side is 105PSI and the high side is 110. With engine off, the low stays the same and high is 110 PSI so pretty much the same
* B107D-15 The Additional Coolant Pump Has A Malfunction, There Is A Short Circuit To Positive Or An Open Circuit. (Did not come back on after clearing the codes)
* B10A2-07 The Actuator Motor For The Left BIend Ar Flap Has A Malfunction, There Is A Mechanical Fault (Did not come back on after clearing the codes)
* P0597-00 The coolant thermostat has an electrical fault or open circuit. There ls A General Failure (Came back after clearing the codes)
* B113-15 Temperature Sensor 'Right Footwell Vent' Has A Malfunction. There Is A Short Circuit To Positive Or An Open Circuit. - Current, Stored. (Came on only after clearing the codes)|
Additionally I ran other tests on the scanner, such as voltage, temperatures etc through Climate Control Data, Actuator Motors and Blower Regulator but I am not sure how to read the data. Below are only a few key information.
I wouldn't want to change the compressor if something else is causing the issue, since it is pretty costly.
"P0597-00 The coolant thermostat has an electrical fault or open circuit. There ls A General Failure (Came back after clearing the codes)" code is pointing the thermostat
"Causes For Shutoff Of Refrigerant Compressor - No Approval Through C.U Combustion Engine'" and this live data is suggesting that the thermostat code is disabling your AC
Could the thermostat be the issue instead of compressor? What is the best way of diagnosing it?
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
First, the low pressure is too high and the high pressure is too low. The fact that they are almost the same makes me think there is a mechanical malfunction or defect. That needs to be resolved before addressing those other faults. I would take it to an automobile a/c specialist and not a generalist mechanic.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
I think the first answer is for a building a/c (i.e., heat pump) and not for a car. BUT, could the compressor still be faulty. The second answer for when a car is off is what we are seeing with your car. I do think this is pointing to a faulty compressor.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
His low pressure is too high, and his high pressure is too low. Again, I suggest he go to an A/C specialist. I'm sure there are a bunch in south Florida.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Would the compressor still turn if the clutch was disabled? In the first post, he states, "The compressor starts spinning when I turn on AC and stops when I turn it off." But there are no corresponding material pressure changes. That is what is confusing me.
I wouldn't want to change the compressor if something else is causing the issue, since it is pretty costly.
"P0597-00 The coolant thermostat has an electrical fault or open circuit. There ls A General Failure (Came back after clearing the codes)" code is pointing the thermostat
"Causes For Shutoff Of Refrigerant Compressor - No Approval Through C.U Combustion Engine'" and this live data is suggesting that the thermostat code is disabling your AC
Could the thermostat be the issue instead of compressor?
What is the best way of diagnosing it?
This is well done troubleshooting... Cleared fault and Tstat came right back again.
Replace it with a reputable part. It's very easy work on non-turbo engines.
The ECU safely disables A/C compressor to prevent aggravating cooling issue.
This is well done troubleshooting... Cleared fault and Tstat came right back again.
Replace it with a reputable part. It's very easy work on non-turbo engines.
The ECU safely disables A/C compressor to prevent aggravating cooling issue.
I've just ordered the Launch scanner that's dedicated for Mercedes so I'll double check the car with this. It is actually a turbocharged 2.0 engine.
Just to add, I had the car in a shop for tire rotation and general maintenance a few weeks prior to the AC issue and I just found that they added a coolant, I called the shop and they said that it was most likely a Peak Violet coolant for european vehicles, which seems to be a G13. This car needs a G40. Could this caused the AC issues?
I assume that the coolant needs to be drained to change the thermostat so I'll flush and change the coolant at the same time.
Would you replace the thermostat only or the thermostat housing as well?
Originally Posted by JettaRed
Would the compressor still turn if the clutch was disabled? In the first post, he states, "The compressor starts spinning when I turn on AC and stops when I turn it off." But there are no corresponding material pressure changes. That is what is confusing me.
I've just ordered the Launch scanner that's dedicated for Mercedes so I'll double check the car with this. It is actually a turbocharged 2.0 engine.
Just to add, I had the car in a shop for tire rotation and general maintenance a few weeks prior to the AC issue and I just found that they added a coolant, I called the shop and they said that it was most likely a Peak Violet coolant for european vehicles, which seems to be a G13. This car needs a G40. Could this caused the AC issues?
I assume that the coolant needs to be drained to change the thermostat so I'll flush and change the coolant at the same time.
Would you replace the thermostat only or the thermostat housing as well?
Great, now you even know why,
where and who
These thermostats are built to be replaced as regular maintenance. Mixing the wrong coolant chemistry may have helped the old Tstat bridge its internal heater element.
There are places that harm cars more than fix them ... twisted caliper hoses, here its coolant. My original MB dealer consistently lost the same tire cap every single time my car went in for service. This ridiculous BS had to be done purposely, at downtown Mercedes dealer.
In addition MB is forced to change coolant chemistry with newer compatible formulas of yellow, blue, pink... so it can be confusing.
Now if your coolant was low, you'll want to find the leak around radiator or engine's rear plastic pipes.
🤞
Last edited by CaliBenzDriver; 05-30-2024 at 04:06 PM.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
I would be very upset with them for using the wrong coolant and request them to do the flush and replacement with the correct coolant. There is an involved process to do it correctly.
I been hunting down my A/C issue on the GLE as well and we think it's the A/C Compressor Control Solenoid Valve (I order one from RKXTech it's in transit). Hope this will solve my issue if not I be swapping out the expansion valve next.
The compressor was not compressing the refrigerant down. The compressor is working it's engaging but when A/C is on the vent is reading 113F-117F (outside temp was above 80F) with my Infrared Laser Thermometer Gun and the scanner was reading those temp as well in live stream. Early morning is ice cold but once the weather temp get's above 70s, warm air start blowing out of the vent. No leak in the system we had it hooked up to a A/C recovery machine
Codes I pulled from a Snap-On Scanner
B119C-07 "at least one of the switches automatic air conditionings jammed"
B2105-9A "The capacity of the starter battery is too low" - I just changed the Aux battery (original one). The main battery was replace before.
You don't really need the equipment they use, but you should use something like this:
Is this required? Is this kit ti drain and flush or just to refill?
Originally Posted by amusa
It's fixed Confirmed the A/C Compressor Control Solenoid valve was the culprit. It was a pain in the rear due to the location
Do you know the part number by any chance?
Thank you guys. A new thermostat will arrive tomorrow so I'll try to swap it. I've been stryggling with finding the right part since my C300 came with amg package and has an option code M014 (Increased Performance engine) and 919 (Aircon cooling power package), which has a bit different thermostat housing type. Additionally I replaced my car battery and voltage regulator which cleared some of the short circuit codes. if that doesn't help I'll try the solenoid or compressor. I also purchased a Launch scanner for Benz and the values are a bit different than Snap On. I'll upload those later today. It does show the compressor running and magnetic clutch opening when turning on AC.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by m4gnum
Is this required? Is this kit ti drain and flush or just to refill?
Well, it doesn't really flush, but is used to refill without leaving any air pockets in the coolant passages. People will probably tell you it doesn't matter, but if it's called for in the WIS, I try to follow it.
I went 3 different shops to diagnose the AC and they couldn't help. All of them wanted to check for leaks, pull and recharge the AC, then replace the compressor and continue with replacing other parts with a discount, if this doesn't solve the issue.
I scanned the car with the Launch scanner and I think I found a few issues. I am including all information below. I know it is a lot but I would really appreciate if someone could help since I am in Florida and the car is not usable for a few weeks due to extreme temperatures.
Additional information:
A9/7y2 (Refrigerant Compressor Magnetic Clutch) is open with AC off, but it's changing to closed as soon as I turn the AC on
M13/5 (Coolant Circulation Pump) stays off with AC on and AC off
I went into A/C Actuation Test and manually turned on M13/5 Coolant Circulation Pump out of curiosity and it did switch to ON, but the air temperature did not change
B10/8 (Rear Center Air Vent Air Outlet Temperature Sensor) stays at -58 F and does not change at all
Also, the automatic diagnostic test did not throw any codes for A/C but when I manually read the fault codes for A/C, it did bring code B19A400 - LIN bus 2 of the air conditioning system has a malfunction
"Governor" power consumption jumps from 0 A to 24 A with AC on. Temperature of "Governor" increased slightly from 165 F to 176 F with AC on. Blower Motor RPM jump from 1100 RPM to 4540 with AC ON.
When I used a scanner a few weeks ago, there was a code P0597-00 (The coolant thermostat has an electrical fault or open circuit. There Is A General Failure). I cleared the codes and it still did not come back, however I made only 15-20 miles since clearing the cods, so I am not sure if I should still try to change the thermostat or not.
Same with code B1113-15 (Temperature Sensor 'Right Footwell Vent Has A Malfunction. There Is A Short Circuit To Positive Or An Open Circuit. Current, Stored). It did not return after clearing the codes.
I replace the battery since last scan check and the voltage errors cleared from the dashboard and not showing in scanner either.
Not sure if these codes are related to AC but these show even after clearing the codes: PO6DA00 (The actuation of the valve of the oil pump in the combustion engine has an electrical fault or open circuit, Current), U014787 Communication with the control unit "Head unit" has a malfunction.The message is missing. STORED), U013200 (Communication with control unit "Suspension" has a malfunction. CURRENT and STORED), C10C800 (There is a warning from the control unit "COLLISION PREVENTION ASSIST" STORED)
Additional information:
"Governor" power consumption jumps from 0 A to 24 A with AC on.
Temperature of "Governor" increased steadily from 165 F to 190 F with AC on.
Blower Motor RPM jump from 1100 RPM to 4540 with AC ON.
Position of 2 Actuator Motors are showing -10000 and other values as 0
Error codes:
B19A400: LIN bus 2 of the air conditioning system has a malfunction.
P0597-00: Coolant thermostat electrical fault or open circuit (cleared but occurred previously).
B1113-15: Temperature Sensor 'Right Footwell Vent' malfunction (cleared but occurred previously).
Key details for anyone who do not want to go over all the details
Symptoms:
AC blowing warm air, no cold air at all.
Heating works fine; air gets warmer when temperature is turned up.
AC compressor starts spinning when turned on, stops when turned off.
Fan behind the radiator engages.
Low pressure is high, High pressure is low
Negative values:
Rear Center Air Vent Air Outlet Temperature Sensor (B10/8): This sensor consistently shows -58°F. I have no idea where this sensor is located and what is the part number.
Refrigerant Pressure Sensor (B12): The readings of 9.80 - 10.50 bar are somewhat high but it is hot outside.
Evaporator Temperature Sensor (B10/6): High readings of around 118-119°F
LIN bus 2 of the air conditioning system has a malfunction (B19A400): Diagnostic test did not throw any codes for A/C but when I manually read the fault codes for A/C, it did bring the code
Some actuator motors show 0 or very high/negative values (-10000), indicating possible faults or misreading, i.e. Rear Center Air Vent Sensor (B10/8)
When I used a scanner a few weeks ago, there was a code - The coolant thermostat has an electrical fault or open circuit. There Is A General Failure (P0597-00). I cleared the codes and it still did not come back, however I made only 15-20 miles since clearing the cods, so I am not sure if I should still try to change the thermostat or not.
EVAP System Vapor Pressure: -58.75 Pa
Positive values:
Coolant Temperature Sensor (B11/4): Normal readings of around 190°F suggest the engine cooling system is working correctly.
A/C Compressor Regulation Valve (A9/7y1): Shows 0 mA when AC is off and jumps to 901 mA when AC is on, indicating that the control signal is reaching the valve.
A/C Compressor Magnetic Clutch (A9/7y2): Shows OPEN when AC is off and CLOSED when AC is on, indicating that the clutch is working properly.
Governor Power Consumption: Jumps from 0A to 24A when AC is on, indicating the compressor is being engaged.
Blower Motor: Jumps from 0 RPM when AC is OFF to 4540 RPM when AC is ON, indicating the blower motor works fine
Not sure:
Actuation of AC Water Valve (Y19/2): has No Actuation at all
Coolant Circulation Pump (M13/5): Off all the time but I am able to turn it on manually with scanner
Just to clarify, the Coolant Temperature 32 F was shown under the option: N33/5 (High-voltage PTC Heater)The AC option test was showing: B11/4 (Coolant Temperature Sensor) - 167 F
Also, to clarify the power request: (Power Request to Component A9 (Refrigerant Compressor) is between 90-100% even at the lowest AC setting.
In addition, I had the sensors checked with a SnapOn scanner a few weeks ago when the outdoor temperature was lower and the results were:
B10/6 (Evaporator Temperature Sensor): 104.7°F
B14 (Outside Temperature Sensor): 89.5°F
Outside Temperature: 83°F
N70b1 (Interior Temperature Sensor With Integrated Fan): 98.4°F
N70b1 (Interior Temperature Sensor With Integrated Fan): Internal Fan: Running
B10/35 (Left Footwell Vent Air Outlet Temperature Sensor): 102.0°F
B10/36 (Right Footwell Vent Air Outlet Temperature Sensor): 103.1°F
B10/31 (Left Side Air Vent Air Outlet Temperature Sensor): 103.1°F
B10/32 (Right Side Air Vent Air Outlet Temperature Sensor): 104.0°F
Coolant Temperature: 167°F
I have another though, my car had a problem with voltage. The battery was load tested and the results were great however the dashboard was constantly showing a message on the dashboard "Stop Vehicle, Shift to P, Leave engine running" and scanner was showing a lot of codes. I changed the voltage regulator (which also has to do with the ECO start/stop) but it did not solve the problem although some of the codes disappeared. Then I replaced the battery and the dashboard message cleared. In the meantime, I also took the car to a shop and they refilled coolant which turned out to be a G13 instead of G40. I am not sure if these could be somehow related to the AC problem. I also purchased a new thermostat due to P0597-00 code but I have not replaced it yet as the code cleared. I am including all the codes which were showing right before the voltage regulator and battery replacement, in spoilet box below:
Spoiler
Overhead Control Panel
B181E-64: The Sensor For The Engine Hood Has A Malfunction. There is an implausible signal. - Stored.
B1F45-00: The Starter Battery Has Excessive Resistance. There Is A General Failure. - Stored.
B210C-13: The Power Supply Is Outside The Valid Range. There Is An Open Circuit. - Stored.
Air Conditioning
B107D-15: The Additional Coolant Pump Has A Malfunction. There Is A Short Circuit To Positive Or An Open Circuit. - Stored.
B10A2-07: The Actuator Motor For The Left Blend Air Flap Has A Malfunction. There Is A Mechanical Fault. - Stored.
Dimming Inside Rear View Mirror
(The same codes as listed under "Overhead Control Panel")
Headlamp - Left
U0132-00: Communication With Control Unit Suspension Has A Malfunction. There Is A General Failure. - Stored.
Panoramic Sliding Roof
U0168-87: Communication with the electronic ignition lock has a malfunction. The message is missing. - Stored.
Signal Acquisition Modules: SAM Module - Front
(The same codes as listed under "Overhead Control Panel")
Signal Acquisition Modules: SAM Module - Rear
B1F25-15: The Output For Warning / Ambient Lamp Lift Gate Has A Malfunction. There Is A Short Circuit To Positive Or An Open Circuit. - Stored.
B1F38-13: The Output For Switch And Controls Illumination Emergency Trunk Lid Release Has A Malfunction. There Is An Open Circuit. - Stored.
Steering Column Module
P172A-29: The Direct Select Lever Has A Malfunction. The Signal Is Invalid. - Stored.
Engine
P0597-00: The coolant thermostat has an electrical fault or open circuit. There Is A General Failure. - Stored.
P06DA-00: The actuation of the valve of the oil pump in the combustion engine has an electrical fault or open circuit. There Is A General Failure. - Current, Pending.
P0563-00: The On-Board Power Supply Voltage Is Too High. There Is A General Failure. - Stored.
Antilock Brakes
C100B-77: The Electric Parking Brake Has A Malfunction. The commanded position cannot be reached. - Stored.
C100B-FA: The Electric Parking Brake Has A Malfunction. - Stored.
C100B-FF: The Electric Parking Brake Has A Malfunction. - Current, Pending, Stored.
Electronic Power Steering
B210F-00: Input 'Circuit 30' Has A Malfunction. There Is A General Failure. - Stored.
Is this required? Is this kit ti drain and flush or just to refill?
Do you know the part number by any chance?
Thank you guys. A new thermostat will arrive tomorrow so I'll try to swap it. I've been stryggling with finding the right part since my C300 came with amg package and has an option code M014 (Increased Performance engine) and 919 (Aircon cooling power package), which has a bit different thermostat housing type. Additionally I replaced my car battery and voltage regulator which cleared some of the short circuit codes. if that doesn't help I'll try the solenoid or compressor. I also purchased a Launch scanner for Benz and the values are a bit different than Snap On. I'll upload those later today. It does show the compressor running and magnetic clutch opening when turning on AC.
You need to look at your AC compressor. There is a manufacture label and your going to need the make and model (Mine was on the bottom of the compressor. I had to remove the belly pan). For example mine is a Denso 7SAS17C. The part number from RKXTech is RKK-RCV-043. Dealer would not sell you the valve but they will sell you a rebuild compressor for allot of $$$. The valve costing me around $50. I gave my nephew $300 to do the job that he won't take money from me. I forced it on him.
You need to discharge the system completely before replacing the valve (under high pressure) then you need to charge up the system afterwards once you install the valve.
You need to lube up the O rings on the new valve with the same oil. My nephew just use the same oil from the old valve O rings.
You need to look at your AC compressor. There is a manufacture label and your going to need the make and model (Mine was on the bottom of the compressor. I had to remove the belly pan). For example mine is a Denso 7SAS17C. The part number from RKXTech is RKK-RCV-043. Dealer would not sell you the valve but they will sell you a rebuild compressor for allot of $$$. The valve costing me around $50. I gave my nephew $300 to do the job that he won't take money from me. I forced it on him.
You need to discharge the system completely before replacing the valve (under high pressure) then you need to charge up the system afterwards once you install the valve.
You need to lube up the O rings on the new valve with the same oil. My nephew just use the same oil from the old valve O rings.
I ordered the valve through RKX however they cancelled my order and I am having a hard time finding these at any other store. The only other place to sell the control valves is Aliexpress but the sellers are very hard to work with. My compressor is 6SAS14C.
What Benz do you have?
Did you have to pull the compressor out to change the valve?
I have a GLE400 (M276, Bi-turbo). He did not removed the compressor. It was in a very tight space. You need allot of patience,
Once he install the valve and recharge the Freon. It took awhile for the Freon to circulate and or the valve to adapt to the ECM while the motor is idling. I would say about 25min before the cold A/C kicked in.
I ordered the valve through RKX however they cancelled my order and I am having a hard time finding these at any other store. The only other place to sell the control valves is Aliexpress but the sellers are very hard to work with. My compressor is 6SAS14C.
What Benz do you have?
Did you have to pull the compressor out to change the valve?
It uses the same part number on the Denso 7SAS17C: The part number is RKX-RCV-043
05-29-2024, 01:00 PM
