SL/R230: A/C issues 2009 SL550
#1
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A/C issues 2009 SL550
Still warm in AZ. 2 days in a row. A/C working fine, then starts blowing warm air. Turn off entire system, wait 10 seconds, hit "Auto" air is now blowing cold and A/C Rest light is on. Turn that off and all is good for 10 minutes. Repeat last three sentences. All is good for 10 minutes, repeat problem again. And over and over. Car is in the shop for A service and A/C check. Curious what I'm going to hear. TIA
#2
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2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
You may be either low or high on refrigerant. Have you added any? Overfilling can cause the A/C not to work properly, and too low is going to cause the compressor to overwork.
The A/C is a sealed system. But if they never leaked, there wouldn't be all of the blindingly expensive A/C recharge kits at the auto parts store. But, not all is lost. On my 2000 Ford F150 beater, the A/C is usually meat locker cold. However, this year it wasn't cooling as much. I found the Schrader valve on the high-pressure line was leaking refrigerant. Simple fix (versus replacing a major component) and I'm back to driving an ice cream truck.
Not sure what the dealer is going to find in your case. If they come back with an estimate of $$$$$, take it to another shop. The biggest challenge is recovering any remaining refrigerant before opening the system.
The A/C is a sealed system. But if they never leaked, there wouldn't be all of the blindingly expensive A/C recharge kits at the auto parts store. But, not all is lost. On my 2000 Ford F150 beater, the A/C is usually meat locker cold. However, this year it wasn't cooling as much. I found the Schrader valve on the high-pressure line was leaking refrigerant. Simple fix (versus replacing a major component) and I'm back to driving an ice cream truck.
Not sure what the dealer is going to find in your case. If they come back with an estimate of $$$$$, take it to another shop. The biggest challenge is recovering any remaining refrigerant before opening the system.
Last edited by JettaRed; 09-29-2023 at 10:29 AM.
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2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Glad to hear!