A/C Heater Regulator Question
#1
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Thread Starter
A/C Heater Regulator Question
Hello Gang,
I wanted to ask the brain trust a question regarding the Heating-A/C System on my 2002 C240 (W203).
When I turn on the system (heater or A/C) cold air comes from the top vents and HOT air comes out at the footwells. Attempting to regulate the flow of air using the switch to the right has no effect. The HOT air comes from both passenger and driver footwells, so I doubt BOTH the left and right footwell actuators went bad at the same time.
I was thinking that Resetting the A/C system may put everything back in Sync.
I read somewhere you can RESET the A/C system by starting the engine depressing the RECURC and DEFROST buttons at the same time. The LEDs will blink RECURC to DEFROST for 30 seconds. Shut off the Engine. Wait 40 seconds restart and apparently the system is reset. Unfortunately in my case the RECURC and DEFROST lights blink and never stop blinking.
HERE IS THE QUESTION:
Any Ideas? Is there another method to reset the A/C system?
Thanks in Advance
I wanted to ask the brain trust a question regarding the Heating-A/C System on my 2002 C240 (W203).
When I turn on the system (heater or A/C) cold air comes from the top vents and HOT air comes out at the footwells. Attempting to regulate the flow of air using the switch to the right has no effect. The HOT air comes from both passenger and driver footwells, so I doubt BOTH the left and right footwell actuators went bad at the same time.
I was thinking that Resetting the A/C system may put everything back in Sync.
I read somewhere you can RESET the A/C system by starting the engine depressing the RECURC and DEFROST buttons at the same time. The LEDs will blink RECURC to DEFROST for 30 seconds. Shut off the Engine. Wait 40 seconds restart and apparently the system is reset. Unfortunately in my case the RECURC and DEFROST lights blink and never stop blinking.
HERE IS THE QUESTION:
Any Ideas? Is there another method to reset the A/C system?
Thanks in Advance
#2
Member
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Thread Starter
For anyone interested here is an update of my situation.
The "Easter Egg" trick to reset your HVAC system by pushing the Defrost and Recirc buttons was the only Non Dealer ODB2 method I found. Systems with the digital displays have another way to test and reset the system (there are plenty of threads that explain how to do that)
One thing important to note that some people report the reset takes 30 seconds to complete, mine took a little longer, maybe 90 seconds, HOWEVER during that time you can hear the actuators redirecting the flow of air throughout the system. So if you do not hear the redirection and/or the LEDS blink for an inordinate amount of time you have some type of system hardware failure.
In my case, there is a bundle of three black wires with a black connector plug with a SIEMENS sticker on it that had somehow worked itself loose. When I replugged it in the system went back to normal. The moral, check your connections first.
I hope this helps someone.
The "Easter Egg" trick to reset your HVAC system by pushing the Defrost and Recirc buttons was the only Non Dealer ODB2 method I found. Systems with the digital displays have another way to test and reset the system (there are plenty of threads that explain how to do that)
One thing important to note that some people report the reset takes 30 seconds to complete, mine took a little longer, maybe 90 seconds, HOWEVER during that time you can hear the actuators redirecting the flow of air throughout the system. So if you do not hear the redirection and/or the LEDS blink for an inordinate amount of time you have some type of system hardware failure.
In my case, there is a bundle of three black wires with a black connector plug with a SIEMENS sticker on it that had somehow worked itself loose. When I replugged it in the system went back to normal. The moral, check your connections first.
I hope this helps someone.