MelVelasquez

Hello,

I own a 2004 CLK500 recently my AC started to fail by not cooling, all I had to do is turn off the car off and it was solved. Now the problem has gotten out of hand that I have to turn on and off the car many times in order for the AC to work.

I already checked everything I could but I haven't been able to figure what the problem is.

any ideas will be helpful.

Mel

Rudeney

First, check to see if the compressor clutch is engaged. If not, then you either have a bad compressor or low refrigerant. If the compressor is operating, it could be a problem in the control unit or the damper system. Try the climate control test/reset: with the engine running, simultaneously press and hold the recirc and front defog button until their indicator lights begin to blink. They should continue to blink for 20-30 seconds then stop. If not, then there is a damper control problem. In either case, if you'll find a shop with SDS< they can pull the diagnostic codes and tell you for certain what the problem is.

Glyn M Ruck

These compressors are swash plate units. They do not have a clutch & run all the time but don't pump with the swash plate vertical. i.e. they pump when an angle is applied to the swash plate by the actuator.

The most likely cause is just low refrigerant pressure. There is a pressure/temp switch below the front condenser. If pressure is too low it shuts down the system to protect the compressor. Turning off & on resets it but it will shut down again if pressure is low.

You can't diagnose anything on these HVAC systems without first having full pressure. Recharge refrigerant to full pressure first.

MelVelasquez

Hello Gyln,

Thank you for your response, I check the Freon levels and it was low, I added 134a freon and I raised up the level up a bit and it worked. at first it took me a while to get the compressor up and once it was up and I loaded freon and the compressor has not shut off. I guess adding more freon did the trick. Thank you for your response. I was afraid I had to spend extra money on trying to resolve this problem. I took it to an MB dealership and they wanted to swap my whole A/C system. I pretty much told them to go F#$% themselves, I knew it had to be something way more simple than that.

MelVelasquez

Rodney,

Thank you also for your answer, adding Freon did the trick

Glyn M Ruck

Great ~ I'm pleased it's sorted. Dealers!!! If you lose pressure again get an HVAC shop to add a dye to the refrigerant to locate the leak.

Good luck!

wcdeane

Forgive me if I misuse the system in any way. This is my first time, and I'm not quite sure how this works. I have 2004 CL500, and the AC quit. The “AC off” button is lit. I read on another thread about resetting the error codes on the climate control unit. I did that, and got an error code “1000”, and it cleared. Now when I go to reset the error codes I get “Error code “- - - - “. However, when I went to check/recharge the refrigerant, I found 100psi on the suction side. So I can’t charge the system. I also tried the climate control test/reset procedure, but the indicator lights did not blink. What might be going on here?


I also saw a thread where someone said there is a reset button that protects the compressor when there is something faulty in the system and that it is located on the condenser. I am wondering if resetting this will allow me to charge the system. Can someone describe what this button looks like and precisely where it is located? I can’t seem to find it.

Any help would be greatly appreciated.

Rudeney

There is no "reset button", but there are pressure sensors on the system. If your compressor will not start, then 100psi is normal on the low side as the system will equalize. It's only when the system is running that the high side goes up and the low side goes down. I think at this point, you may nee some professional help with the right test equipment to see what is going on.

wcdeane

Thanks Rodney.

wcdeane

I also tried the climate control test/reset procedure, but the indicator lights did not blink. Other threads suggest that the indicator lights should blink. Is that a sign that there might be a problem with the climate control module?

Rogue-CLK

Did the procedure and it wouldn't stop blinking, what does that mean?

P4r4d1s

Hi, my ac reset button won't turn off, it's the analogue version. It's driving me mental, please help. Thanks

Rudeney

So the lights continue to blink after 20-30 seconds? This means something is wrong in the ACC system, often a broken damper servo in the ducts. You'll need to get a proper diagnosis to know for sure.