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Shouldn't these throw a code though? I got no DTCs
Codes are in the same league with the money light.
They are not here to help, only token for the real problem that's infact usually somewhere else.
To make decisive progress, you've got to analyze available evidence/clues while answering:
is it A or B else C.
Here you have medium pressure thats not pumped up... prop. valve!
Before rushing at opening sealed circuit, you check differential pressures to confirm compressor is not pumping besides commanded at 100% duty.
The wobling plate is staying idle.
without replacing while unit Toyota uses the same compressor with spare parts available.
R134A pressure and temperature is interelated. When at X temperature, it has to be at Y pressure.
Attached the pressure temp chart
Make sure engine is at ambient temperature ( 12 hours shut down minimum ) and use the Launch to see the pressure.
Compare it to the attached chart. based on the temperature reading of the engine metal or ambient.
Pressure alone can not verify R134A fill is proper or not proper, even at 50% gone, you will still get the pressure as per temperature.
The typical natural loss via the compressor seal is 8 grams per year. Your car R134A fill woud be close to mine at 590grams....but must check WIS.
Only RRR machine or equivallent can confirm your refrigerant fill level in grams. You can not use pressure to define proper R134A fill...NO WAY.
Scenario 1 :
If yours is clutchless AC compressor , that means no B09* option .... it is most likely that AC valve is the issue.
*B09 option means AC comp has clutch.
Albeit you are seeing power sent to the AC solenoid, that up to 950milliamps of current, that does not guarantee the AC valve actually open up.
Scenario 2 : Which is most unlikely....I pray it is not the case
Your AC compressor is shot, it can't produce pressure at all as in total loss of compression...again , it won't be this bad suddenly, it will be progressive.
As to why you seeing pressure rise to 7.x BAR, is because when engine is ON, it heats up the HVAC component and pipe and thus raise R134A pressure by virtue of slowly rising hotter temperature.
Last edited by S-Prihadi; May 8, 2025 at 04:26 AM.
R134A pressure and temperature is interelated. When at X temperature, it has to be at Y pressure.
Attached the pressure temp chart
Make sure engine is at ambient temperature ( 12 hours shut down minimum ) and use the Launch to see the pressure.
Compare it to the attached chart. based on the temperature reading of the engine metal or ambient.
Pressure alone can not verify R134A fill is proper or not proper, even at 50% gone, you will still get the pressure as per temperature.
The typical natural loss via the compressor seal is 8 grams per year. Your car R134A fill woud be close to mine at 590grams....but must check WIS.
Only RRR machine or equivallent can confirm your refrigerant fill level in grams. You can not use pressure to define proper R134A fill...NO WAY.
Scenario 1 :
If yours is clutchless AC compressor , that means no B09* option .... it is most likely that AC valve is the issue.
*B09 option means AC comp has clutch.
Albeit you are seeing power sent to the AC solenoid, that up to 950milliamps of current, that does not guarantee the AC valve actually open up.
Scenario 2 : Which is most unlikely....I pray it is not the case
Your AC compressor is shot, it can't produce pressure at all as in total loss of compression...again , it won't be this bad suddenly, it will be progressive.
As to why you seeing pressure rise to 7.x BAR, is because when engine is ON, it heats up the HVAC component and pipe and thus raise R134A pressure by virtue of slowly rising hotter temperature.
Thank you for chiming in, I noticed the a/c compressor is rusting on inspection, anyways I have enough information from all of you to work with.
Codes are in the same league with the money light.
They are not here to help, only token for the real problem that's infact usually somewhere else.
To make decisive progress, you've got to analyze available evidence/clues while answering:
is it A or B else C.
Here you have medium pressure thats not pumped up... prop. valve!
Before rushing at opening sealed circuit, you check differential pressures to confirm compressor is not pumping besides commanded at 100% duty.
The wobling plate is staying idle.
without replacing while unit Toyota uses the same compressor with spare parts available.
Go back to the charts I posted in #882. You can also search HVAC Symptoms Chart or something like that.
These may be simpler:
Helpful chart, thank you I will check both yours and MS : ) Thank you all 3 of you for helping. There are no drips after parking the vehicle so clearly a/c is not working. Is it normal for there to be a whistle sound (relatively faint) when a/c is on, it is not whistling from the vents when it is off. I do recall this whistle sound is there even before a/c quit. Any suggestions on what the whistle sound is?
Last edited by W205C43PFL; May 8, 2025 at 01:01 PM.
Since I have no water dripping at all, I have a bad feeling is scenario 2 mentioned, a failed compressor. Oh boy. Is it true that if you don't use the a/c often it fails easily? I rarely use the a/c in my car for example.
Since I have no water dripping at all, I have a bad feeling is scenario 2 mentioned, a failed compressor. Oh boy. Is it true that if you don't use the a/c often it fails easily? I rarely use the a/c in my car for example.
A/C system control is the perfect service need for electric cars along with goofy door + trunk modules.
Ppl say A/C oil needs to be circulated. There's no trace of corrosive water inside. Seals get hard due to extreme heat.
A/C system control is the perfect service need for electric cars along with goofy door + trunk modules.
Ppl say A/C oil needs to be circulated. There's no trace of corrosive water inside. Seals get hard due to extreme heat.
This makes sense, just how engine oil needs to be circulated to prevent seals from drying up, next time I should turn on the a/c while wearing a jacket during a blizzard, just to make sure the compressor gets run in the winter.
This makes sense, just how engine oil needs to be circulated to prevent seals from drying up, next time I should turn on the a/c while wearing a jacket during a blizzard, just to make sure the compressor gets run in the winter.
.... A/C PAG synthetic oil is not shared with dirty engine oil...
You know what's a small world with oil topic ??
compressor oil is used to seal 200.Psi compression of 5x pistons.... much like 5w-50 oil for engine wet ring seal. Less pressure losses means more efficiency !!
Last edited by CaliBenzDriver; May 8, 2025 at 05:15 PM.
.... A/C PAG synthetic oil is not shared with dirty engine oil...
You know what's a small world with oil topic ??
compressor oil is used to seal 200.Psi compression of 5x pistons.... much like 5w-50 oil for engine wet ring seal. Less pressure losses means more efficiency !!
I mean as an example : ) as in parts need fluids circulating.
I mean as an example : ) as in parts need fluids circulating.
That's a very good question
I think it is the seals in the PWM solenoid valve that are guaranteed to hold back the plunger. That holds the compress plate near neutral, unable to pump up gas into liquid.
Last edited by CaliBenzDriver; May 8, 2025 at 08:10 PM.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
I always run my A/C throughout the year to keep the seals properly conditioned. Modern compressors no longer put a drag on the engine like they did 40-50 years ago. In the winter, having the A/C on helps keep the inside dry (from fogging the windows). In the summer, well...to stay cool.
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