03 C240 No A/C
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2003 C240
03 C240 No A/C
Not original radiator fan, Bad stepper motor because air blow constantly through footwell, and Ac off light stuck on I tried to recharge it but I think it didn't take it. Did the Climate reset but still couldn't get anything to happen. Any help would be GREATLY appreciated 
had the car for 3 years with no A/c in Florida. 
I'm 20 and its my second car and I plan to keep it.
Got the car with 180K now its at 224K replaced
Fuel pump
Fuel Sender
Crank PS
Alternator
MAF
Breather hoses
Rotors
Brakes
Battery
Trans flush
I do have one stepper motor with the flap linkage.
I do all the work on the car. It's been great to me very reliable since those parts. I just have to clean the Throttle every couple months it seems to get dirty quick and causes the car to stop working normal.
This a/c is the last thing until I can do cosmetic upgrades.
had the car for 3 years with no A/c in Florida. I'm 20 and its my second car and I plan to keep it.
Got the car with 180K now its at 224K replaced
Fuel pump
Fuel Sender
Crank PS
Alternator
MAF
Breather hoses
Rotors
Brakes
Battery
Trans flush
I do have one stepper motor with the flap linkage.
I do all the work on the car. It's been great to me very reliable since those parts. I just have to clean the Throttle every couple months it seems to get dirty quick and causes the car to stop working normal.
This a/c is the last thing until I can do cosmetic upgrades.
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2003 C240
The self diagnosis is when you press two button i think its the defrost and the recirculation button together. Am I right ? It checks all vents and the lights are supposed to stop flashing. When i do it mines keep blinking back and forth after it runs through all the vents.
also I would like to ride through the rain with the windows up.
also I would like to ride through the rain with the windows up.
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Joined: Mar 2007
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From: VA
THE C350
Lol Plutoe be nice the newbies!!
Sadly he is right you need a shop with star to see what stepper motors are acting up. You can try to guess which one is messed up but in the end the dash is a PIA to take apart (did it on my w203 and don't know how I got it back together)
With star it will tell you exactly which one is causing the issue.
Call around your area to the local MB indy's and European shops I am sure one has a star machine. Or if you want to be cool like us go buy a star machine since you are DIY type guy it will make the dealer not needed unless you want a new key/EIS.
As for fixing the Freon side of things you need to pull a vacuum on the system and start over this is usually left to shops as they have the Freon recovery devices but where did all the Freon go? That is what you need to find out.
You a putting a ton of money in an old w203 and as those miles climb the more stupid expensive problems that will come up just keep that in mind
Sadly he is right you need a shop with star to see what stepper motors are acting up. You can try to guess which one is messed up but in the end the dash is a PIA to take apart (did it on my w203 and don't know how I got it back together)
With star it will tell you exactly which one is causing the issue.
Call around your area to the local MB indy's and European shops I am sure one has a star machine. Or if you want to be cool like us go buy a star machine since you are DIY type guy it will make the dealer not needed unless you want a new key/EIS.
As for fixing the Freon side of things you need to pull a vacuum on the system and start over this is usually left to shops as they have the Freon recovery devices but where did all the Freon go? That is what you need to find out.
You a putting a ton of money in an old w203 and as those miles climb the more stupid expensive problems that will come up just keep that in mind
Last edited by samaritrey; Jul 1, 2015 at 01:14 PM.
Thread Starter
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2003 C240
That sounds scary. Its been a year since the car kept me stuck in the middle of the road every month. Oh yea since i replaced my fuel pump and sender the fuel gauge reads correctly until below half a tank then its possible it will shut off. One day I checked both sides when it was around half a tank and one side was just about full and the other was bone dry. Can you help me with that also ? I was thinking if i hooked it up wrong it shouldn't start up. both the pump and sender looked different and came with new wires than the old one. I've searched other threads on it but they all end up a dead end.
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Joined: Nov 2007
Posts: 171
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From: ontario, Canada
C230 COUPE 2003 M271
just some ideas. when i had similar issues with my vw i hooked 12volts up to the ac compressor and that turned it on manually and got me by enough to add refrigerant. when topped up the, the pressure sensor was activated on and compressor would now work from the switch in the car.
I did the stepper motor and linkage fix in my c230. the hardest part was that i also needed a stepper replaced for the windshield defrost. most of the time that the air is stuck on the wheel wells it is due to the broken linkage which doesnt even cost $20 and its just behind the radio as per the instructions in the sticky on the first page in the forum. if you are mechanically minded with basic tools including the inverted torx sockets you can do this in a few hours at most.
I would also be concerned about leaks in the condensor if it has been removed and put back with the new radiator fan or somehow disturbed enough to cause a leak. i would put leak seal and dye in first to see if it can even hold a charge.
I did the stepper motor and linkage fix in my c230. the hardest part was that i also needed a stepper replaced for the windshield defrost. most of the time that the air is stuck on the wheel wells it is due to the broken linkage which doesnt even cost $20 and its just behind the radio as per the instructions in the sticky on the first page in the forum. if you are mechanically minded with basic tools including the inverted torx sockets you can do this in a few hours at most.
I would also be concerned about leaks in the condensor if it has been removed and put back with the new radiator fan or somehow disturbed enough to cause a leak. i would put leak seal and dye in first to see if it can even hold a charge.
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2003 C240
See I thought of that. Yes im mechanically and electrically inclined and have the basic tools. Before I had the car it was an old mechanic who used to work on it. He rigged up a few things which I have replaced all except a few double sided screws stuck in the rotor and the universal radiator fan. I did install a switch on the fan because it came on soon as the key was turned to the 2nd position. I don't think he removed the compressor though.
Im going to get someone to vacuum out the system and hook up 12v to the compressor and charge it this weekend. Any help you can give me on this ? I'll wait to hear an answer. First I'll try and tackle the stepper motor.
Im going to get someone to vacuum out the system and hook up 12v to the compressor and charge it this weekend. Any help you can give me on this ? I'll wait to hear an answer. First I'll try and tackle the stepper motor.
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Member
Joined: Nov 2007
Posts: 171
Likes: 1
From: ontario, Canada
C230 COUPE 2003 M271
See I thought of that. Yes im mechanically and electrically inclined and have the basic tools. Before I had the car it was an old mechanic who used to work on it. He rigged up a few things which I have replaced all except a few double sided screws stuck in the rotor and the universal radiator fan. I did install a switch on the fan because it came on soon as the key was turned to the 2nd position. I don't think he removed the compressor though.
Im going to get someone to vacuum out the system and hook up 12v to the compressor and charge it this weekend. Any help you can give me on this ? I'll wait to hear an answer. First I'll try and tackle the stepper motor.
Im going to get someone to vacuum out the system and hook up 12v to the compressor and charge it this weekend. Any help you can give me on this ? I'll wait to hear an answer. First I'll try and tackle the stepper motor.
Member
Joined: Nov 2007
Posts: 171
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From: ontario, Canada
C230 COUPE 2003 M271
I cant speak on all the sensors in this car but I have had a compressor that would not turn on due to a failed coolant temperature sensor (one specifically for ac system only) I replaced the sensor for $30 from the dealer and it worked perfectly. but I had a good bently manual for my vw that told the proceedure and test values ohms/volts etc to check the sensors properly.
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2003 C240
Good News
Well it took a month but I finally fixed my A/c. I bought a vacuum pump and the gauge set $200. Attached 12V to the compressor I noticed the idle changed when it did so I Knew it was working. Vacuumed it out and left the vacuum in it for about 30 mins it stayed so I figured no leaks. Refilled it and it worked !!! 
But only the passenger side is blowing cold. I had an old stepper motor and linkage I bought a while back so I took apart the dash and installed only the linkage because I noticed the motor still worked. It was for the footwell. Now it works fine only thing is the passenger side is still a little cooler than the driver side. OH, I installed a switch to turn the compressor on and off. I need to plug it back up regularly to see if the A/C off light will go off.
Now I can cruise feeling good and chicks would like to ride in my car once again
Thank you for your help
But only the passenger side is blowing cold. I had an old stepper motor and linkage I bought a while back so I took apart the dash and installed only the linkage because I noticed the motor still worked. It was for the footwell. Now it works fine only thing is the passenger side is still a little cooler than the driver side. OH, I installed a switch to turn the compressor on and off. I need to plug it back up regularly to see if the A/C off light will go off.Now I can cruise feeling good and chicks would like to ride in my car once again
Thank you for your help
Member
Joined: Nov 2007
Posts: 171
Likes: 1
From: ontario, Canada
C230 COUPE 2003 M271
Well it took a month but I finally fixed my A/c. I bought a vacuum pump and the gauge set $200. Attached 12V to the compressor I noticed the idle changed when it did so I Knew it was working. Vacuumed it out and left the vacuum in it for about 30 mins it stayed so I figured no leaks. Refilled it and it worked !!! But only the passenger side is blowing cold. I had an old stepper motor and linkage I bought a while back so I took apart the dash and installed only the linkage because I noticed the motor still worked. It was for the footwell. Now it works fine only thing is the passenger side is still a little cooler than the driver side. OH, I installed a switch to turn the compressor on and off. I need to plug it back up regularly to see if the A/C off light will go off.
Now I can cruise feeling good and chicks would like to ride in my car once again
Thank you for your help
But only the passenger side is blowing cold. I had an old stepper motor and linkage I bought a while back so I took apart the dash and installed only the linkage because I noticed the motor still worked. It was for the footwell. Now it works fine only thing is the passenger side is still a little cooler than the driver side. OH, I installed a switch to turn the compressor on and off. I need to plug it back up regularly to see if the A/C off light will go off.Now I can cruise feeling good and chicks would like to ride in my car once again
Thank you for your help
edit; Mostly can you tell me how you installed the switch, because I was asking last week and got no help
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2003 C240
If you look from under the car on the compressor more to the back of it you should see two wires coming out of it. you can just cut those but far enough from it so you can reattach it when you want to.
If you need pics let me know ill be glad to go take some of my set up for you.
And for the switch I bought a $6 toggle on-off-on switch and its going to have three prongs. Put the positive from the compressor to the battery and.... You know what give me like 10-20 mins its easier if i just take pictures then explain it.
If you need pics let me know ill be glad to go take some of my set up for you.
And for the switch I bought a $6 toggle on-off-on switch and its going to have three prongs. Put the positive from the compressor to the battery and.... You know what give me like 10-20 mins its easier if i just take pictures then explain it.
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2003 C240
If you looking from under the driver front tires the wires lead to the spot.
This is what you plug the wires into
Black = ( - )
Red = ( + ) ofcourse
You need a longer negative wire for the switch. Split the negative in half and put one end on just one of the prongs and the other on two of the prongs then from there lead the wire straight to the battery.
All the way to the left is on, but the middle and the right is off.
If you don't wire it like this it wont work. You can just run the positive straight to the battery I like using the ground as a kill switch.
The switch is $6 at advance auto parts but they also sell them at walmart.
Hopefully this helps.
... I kind of wanted to take a pic of my Vacuum pump and gauges to show what I used to get the job done. Im just SOOO happy to have A/c now !
Last edited by C240Keese; Aug 11, 2015 at 10:02 PM.
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