What is a AC clutch diode?
The wires that go to the AC clutch are usually filled with a diode. It prevents the compressor from going back into the wire and overloading the circuit when it goes off.
What to do if your a / C clutch is not working?
When the A/C system does not blow cold air the first thing that you show check is if the compressor engages. If it doesn’t do not assume that the A/C compressor itself is the problem. Remember that the A/C clutch is controlled by the A/C Control Unit. If that unit detects an error it will not engage the A/C compressor to avoid it getting damaged.
Why is the clutch not engaged on my Mercedes?
Remember that the A/C clutch is controlled by the A/C Control Unit. If that unit detects an error it will not engage the A/C compressor to avoid it getting damaged. One other reason why the A/C compressor does not engage is the fact that the system may be low on R134 refrigerant.
How to tell if your a / C compressor clutch is working / engaging?
If there are error codes on the A/C Control Unit the compressor will not engage and you will need to reset the fault codes using a diagnostic scanner such as the Launch Creader or iCarsoft MB II. How to tell if your air conditioner AC compressor clutch is working / engaging?
Why does the clutch not engage in a low pressure car?
If the PCM (powertrain control module) senses low pressure in the low pressure fluid line, it will stop the compressor clutch from engaging to prevent any damage. This is because low pressure = low fluid, and r 134a is also oil/lubricant for the compressor and if you don’t have fluid then you will damage the compressor.
What does it mean when your a / C clutch does not engage?
If the Compressor doesnt engage with direct power from the battery then the Compressor is shot. Sorry also jump the high pressure switch.. IF the still doesnt engage it then you need to run power directly to the AC compressor and see if the compressor engages then.
If there are error codes on the A/C Control Unit the compressor will not engage and you will need to reset the fault codes using a diagnostic scanner such as the Launch Creader or iCarsoft MB II. How to tell if your air conditioner AC compressor clutch is working / engaging?
If the PCM (powertrain control module) senses low pressure in the low pressure fluid line, it will stop the compressor clutch from engaging to prevent any damage. This is because low pressure = low fluid, and r 134a is also oil/lubricant for the compressor and if you don’t have fluid then you will damage the compressor.
How to troubleshoot a / C compressor clutch problems on your Mercedes?
This video is helpful if you are trying to troubleshoot air conditioner problems, the A/C compressor clutch in particular. This opens in a new window. Start by turning the engine on. Set the AC to maximum cold setting. Open the hood and look at the serpentine belt to locate the AC compressor.