I have a 1999 ML320 and my A/C is not cooling! Had refrigerant checked and was told that it was fully charged. Also, checked fuses just to see if that could be the problem. My air runs through the car, but just doesn't cool and fans in front of engine will not come on. Any ideas where to check and if it is the fans, how do I check to make sure they're getting power?
1999 ML320 Air Cond Fans not working!
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94 S420 RIP 2/8/13 02 ML55AMG, 06 CLS55AMG, 89 Mas. 228, 84 Por. 911 Carrera, 93 Toyota t.t. Supra
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Does the compressor turn on? The system is such that when the a/c is activated the rpm increases slightly, the compressor kicks on and the fan on the front of the radiator should go on. Did you check the associated relay? If it's fully charged the compressor shut down switch (don't recall the correct name but it senses pressure and shuts the system down if there is insufficient charge.) should not be activated. My money is on a relay. Good luck.
1. first check to see that fuse #44 is not blown. If not..........
2. swap relay K26 (fans) with K21 (blower motor). If not.......
3. start engine and press A/C switch and see that the compressor clutch (red arrow) turns continuously. Does it?
If it doesn't there is a 99% probability that you are low on refrigerant, regardless of what your mechanic has said. The only way to determine if you have the proper amount of refrigerant in the system is to evacuate the refrigerant and see by how many ounces was evacuated.
2. swap relay K26 (fans) with K21 (blower motor). If not.......
3. start engine and press A/C switch and see that the compressor clutch (red arrow) turns continuously. Does it?
If it doesn't there is a 99% probability that you are low on refrigerant, regardless of what your mechanic has said. The only way to determine if you have the proper amount of refrigerant in the system is to evacuate the refrigerant and see by how many ounces was evacuated.
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Hey guys, I also have a problem where the electric fans in front of the radiator do not come on.
1. first check to see that fuse #44 is not blown.
- This fuse in my car is not blown
2. swap relay K26 (fans) with K21 (blower motor).
- I've swapped the relays and the fans do not come on
3. start engine and press A/C switch and see that the compressor clutch (red arrow) turns continuously.
- My A/C compressor spins and the A/C is cold.
I never see or hear this A/C fans come on - irregardless of the engine temperature.
Any help would be appreciated. Thank you.
1. first check to see that fuse #44 is not blown.
- This fuse in my car is not blown
2. swap relay K26 (fans) with K21 (blower motor).
- I've swapped the relays and the fans do not come on
3. start engine and press A/C switch and see that the compressor clutch (red arrow) turns continuously.
- My A/C compressor spins and the A/C is cold.
I never see or hear this A/C fans come on - irregardless of the engine temperature.
Any help would be appreciated. Thank you.
The electric fans will only come on when the engine/coolant temp. goes above a certain degree and/or if the refrigerant pressure goes above a certain degree.
Given the cool weather in NY it is not enough to raise the refrig. pressure temp. and the fans will not turn on. The belt driven clutch fan is enough until the weather gets hotter when the elec. fans will kick in.
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