Going crazy with my GLE400 (86k miles) W166 had the machine hooked up Hi and low side are good. Compressor is engaging. Early morning it blows cold during the summer month just warm air blowing. When I put it on heat it blows plenty of heat. I'm kind of lost here between, control valve (on the compressor), pressure switch on the condenser and or expansion valve. I ran my MBII ICarsoft scanner in live value reading the only thing I see very high temperature reading on the sensor. and air vents. I even checked the vents with my Infrared Thermometer gun and it was reading 110-113F. I have access to MB Star tool. While we had it on the machine and we kicked the A/C on the Low side jerks. I'm going to have my nephew (BMW/Honda tech) look at it it.
Awesome video. I usually DIY everything in my car because I've had terrible experiences with techs in my area, but AC and electrical issues are NOT my thing at all. But now I'm having AC issues on my 2010 ML350 and your video is super helpful. AC is blowing warm throughout, but occasionally gets slightly cool on the passenger's side (never cool on the driver's side, always warm). I also hear an audible hiss/screech noise when I turn in the "AC/ON Rest" button. It fades gradually in about a minute or 2 when I turn it off. Back when the AC was working, if I opened the hood of the car, I would see cold water from condensation gathered on the pipe in the engine bay that runs from what I believe is the expansion valve (the pipe runs from under the windshield wipers location). Now that the AC isn't blowing cold anymore, that pipe is dry and warm. Would this also be an indication of a bad evaporator or something else? I also used to have a decent amount of water puddled under the car whenever I ran the AC, but now I barely see a few drops, if at all. I don't have manual guages yet but I have Xentry/DAS and there are no error codes, but it shows varying refrigerant pressure at anywhere from 7.5 bar to 11.5 bar depending on the fan/temp level. I would appreciate any pointers, thanks!
First is to get a set of gauges and check the pressure. Of course, if the pressure is low, then finding a leak can be difficult. You'd have to get some leak detector dye and follow that process. But if your pressures are good, it could easily be your expansion valve. And sometimes, taking it to an AC mechanic is the way to go. At least for a diagnosis.
Good morning. My ML350 w166 is blowing cold on passenger side and warm on drivers side. Blend door actuator seems to be working fine. Gauges show 150 on high side. Slowly creeps to 200 then cycles back to 150. Low side is 28 when high is 150 and 36 when high is 200. Shut the car off, and pressures are still way off after 30 minutes. Expansion valve? I’m just not understanding why one side is cold and one side is warm. Thank you!
Do you have an OBD reader that will check the AC components? It sounds like a blend door actuator. There is more than one on the car. But I'd say look at the OBD data to see if the blend door actuators are reported working. Pressures not equalizing relatively quickly is usually the expansion valve. With the pressures not equalizing I'd replace the expansion valve. Then if the pressures equalized quickly after shutting it off, but you still had one side cold and the other hot, I'd look further into the actuator door.
Hello Frank. I got a 2016 C300. The ac is blowing hot. I hooked up the gauges and the static pressure are 85 on the low and 150 on the high. I then started the car, turned the A/C on, confirmed that the clutch engaged but the pressures never moved. Is this an indication that my compressor failed? Thanks
Could be the TXV . Something is preventing the pressures from equalizing. With the engine off, both the high side and low side should be the same. Then as the car is started and the compressor kicks in, the high side should increase and the low side decrease. With both being unequal and unchanging, there is a restriction somewhere - usually the TXV. I'd replace the TXV. But you may also need to replace the compressor as well. With my car, I replaced the TXV, the compressor and the dehydrator (videos on all of them).
thats helped me alot , next week i will change the axpansion valve in my mercedes , amazing job appreciate sir .
Perfect work, appreciate
Thank you
Going crazy with my GLE400 (86k miles) W166 had the machine hooked up Hi and low side are good. Compressor is engaging. Early morning it blows cold during the summer month just warm air blowing. When I put it on heat it blows plenty of heat. I'm kind of lost here between, control valve (on the compressor), pressure switch on the condenser and or expansion valve. I ran my MBII ICarsoft scanner in live value reading the only thing I see very high temperature reading on the sensor. and air vents. I even checked the vents with my Infrared Thermometer gun and it was reading 110-113F. I have access to MB Star tool.
While we had it on the machine and we kicked the A/C on the Low side jerks. I'm going to have my nephew (BMW/Honda tech) look at it it.
A/C Compressor Control Solenoid valve was the culprit
Awesome video. I usually DIY everything in my car because I've had terrible experiences with techs in my area, but AC and electrical issues are NOT my thing at all. But now I'm having AC issues on my 2010 ML350 and your video is super helpful. AC is blowing warm throughout, but occasionally gets slightly cool on the passenger's side (never cool on the driver's side, always warm). I also hear an audible hiss/screech noise when I turn in the "AC/ON Rest" button. It fades gradually in about a minute or 2 when I turn it off. Back when the AC was working, if I opened the hood of the car, I would see cold water from condensation gathered on the pipe in the engine bay that runs from what I believe is the expansion valve (the pipe runs from under the windshield wipers location). Now that the AC isn't blowing cold anymore, that pipe is dry and warm. Would this also be an indication of a bad evaporator or something else? I also used to have a decent amount of water puddled under the car whenever I ran the AC, but now I barely see a few drops, if at all. I don't have manual guages yet but I have Xentry/DAS and there are no error codes, but it shows varying refrigerant pressure at anywhere from 7.5 bar to 11.5 bar depending on the fan/temp level. I would appreciate any pointers, thanks!
First is to get a set of gauges and check the pressure. Of course, if the pressure is low, then finding a leak can be difficult. You'd have to get some leak detector dye and follow that process. But if your pressures are good, it could easily be your expansion valve. And sometimes, taking it to an AC mechanic is the way to go. At least for a diagnosis.
Good morning. My ML350 w166 is blowing cold on passenger side and warm on drivers side. Blend door actuator seems to be working fine. Gauges show 150 on high side. Slowly creeps to 200 then cycles back to 150. Low side is 28 when high is 150 and 36 when high is 200. Shut the car off, and pressures are still way off after 30 minutes. Expansion valve? I’m just not understanding why one side is cold and one side is warm. Thank you!
Do you have an OBD reader that will check the AC components? It sounds like a blend door actuator. There is more than one on the car. But I'd say look at the OBD data to see if the blend door actuators are reported working. Pressures not equalizing relatively quickly is usually the expansion valve. With the pressures not equalizing I'd replace the expansion valve. Then if the pressures equalized quickly after shutting it off, but you still had one side cold and the other hot, I'd look further into the actuator door.
Hello Frank. I got a 2016 C300. The ac is blowing hot. I hooked up the gauges and the static pressure are 85 on the low and 150 on the high. I then started the car, turned the A/C on, confirmed that the clutch engaged but the pressures never moved. Is this an indication that my compressor failed? Thanks
Could be the TXV . Something is preventing the pressures from equalizing. With the engine off, both the high side and low side should be the same. Then as the car is started and the compressor kicks in, the high side should increase and the low side decrease. With both being unequal and unchanging, there is a restriction somewhere - usually the TXV. I'd replace the TXV. But you may also need to replace the compressor as well. With my car, I replaced the TXV, the compressor and the dehydrator (videos on all of them).
@@letsrolldiyauto1532 Thanks, I’m going after the TXV first. If this doesn’t fix it I’ll do the compressor. Again thank you very much.
What's it mean when low side is high and high side is normal
Can be a number of things. Bad compressor, bad expansion valve or clogged orifice.
Most of the time, its usually the control valve on the compressor that needs replacing.
Would that cause one side to be cold while drivers side stays warm when running ac?