SL/R129: Help with sl500 heater mono valve
Thread Starter
Newbie
Joined: May 2018
Posts: 7
Likes: 1
sl500 2001 R129
Help with sl500 heater mono valve
hey every one
i hope you guys can help me.!!
i have an amazing sl500 2001 R129
and i have a problem with my heater mono valve.
When I turn on my ac there is cold out from the center and heat from all over (the 2 sides and from up and down to the legs)
now I checked the mono valve and it's perfect the problem is from the connector.
(I connected a battery directly to the mono valve and all was perfect inside the car. Everything is cold!)
my question is :
-there is a fuse that I missed? If there is one.
-where is this connector wires going..?
-from where the mono valve gets is commende to start working..?
pls help guys.. I dig all over and didn't find. I really don't want to do a menual tap.
Thanks to all!
i hope you guys can help me.!!
i have an amazing sl500 2001 R129
and i have a problem with my heater mono valve.
When I turn on my ac there is cold out from the center and heat from all over (the 2 sides and from up and down to the legs)
now I checked the mono valve and it's perfect the problem is from the connector.
(I connected a battery directly to the mono valve and all was perfect inside the car. Everything is cold!)
my question is :
-there is a fuse that I missed? If there is one.
-where is this connector wires going..?
-from where the mono valve gets is commende to start working..?
pls help guys.. I dig all over and didn't find. I really don't want to do a menual tap.
Thanks to all!
Banned
Joined: Jan 2006
Posts: 1,982
Likes: 393
From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Unless there is a wiring problem, I presume you have 12 volts DC supplied to the monovalve, since the valve, coolant circulation pump, and pneumatic control valve for the various HVAC flaps share a common power source.
At the electrical connector to the valve you should have constant 12 volts at the socket from the yellow/grey wire. The controller operates the valve by grounding the wire to the other socket.
At the electrical connector to the valve you should have constant 12 volts at the socket from the yellow/grey wire. The controller operates the valve by grounding the wire to the other socket.
Thread Starter
Newbie
Joined: May 2018
Posts: 7
Likes: 1
sl500 2001 R129
Unless there is a wiring problem, I presume you have 12 volts DC supplied to the monovalve, since the valve, coolant circulation pump, and pneumatic control valve for the various HVAC flaps share a common power source.
At the electrical connector to the valve you should have constant 12 volts at the socket from the yellow/grey wire. The controller operates the valve by grounding the wire to the other socket.
At the electrical connector to the valve you should have constant 12 volts at the socket from the yellow/grey wire. The controller operates the valve by grounding the wire to the other socket.
Thread Starter
Newbie
Joined: May 2018
Posts: 7
Likes: 1
sl500 2001 R129
I don't think soo..
becuse if I connect direct power the valve is working and the ac doesn't make any problem.
I do a little test and the mono valve get +
the problem is from the other line.
My guess is the problem from the push buttons (the red for heat and blue for cold) inside the car.
If im wrong just let me know..
becuse if I connect direct power the valve is working and the ac doesn't make any problem.
I do a little test and the mono valve get +
the problem is from the other line.
My guess is the problem from the push buttons (the red for heat and blue for cold) inside the car.
If im wrong just let me know..
Thread Starter
Newbie
Joined: May 2018
Posts: 7
Likes: 1
sl500 2001 R129
Solve the problem
Ok guys im very happy to say that I solved my problem..
start to think what the heck is operating the mono valve.. the answer is : the climate control..!!
soo just before I order a new one i take my climate control out and for my surprise the main connector wasn't connect all the way in like it should be..
soo I connect like it should be and evwalla its working perfect!! When I wanna heat it's giving me heat. And when I want cold its colllddd
i hope if someone will having the same problem it will help him!
start to think what the heck is operating the mono valve.. the answer is : the climate control..!!
soo just before I order a new one i take my climate control out and for my surprise the main connector wasn't connect all the way in like it should be..
soo I connect like it should be and evwalla its working perfect!! When I wanna heat it's giving me heat. And when I want cold its colllddd
i hope if someone will having the same problem it will help him!
Newbie
Joined: Jun 2020
Posts: 3
Likes: 0
From: New Jersey Shore
95 SL500
Yossiav, I have same problem. Cold out the two center vents, hot out the side vents! Where is the climate control? How do you access the wiring? I would love to speak with you. Phil 908 433 0489
Last edited by Phil Unger; Aug 17, 2020 at 10:26 AM.
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Thread Starter
Newbie
Joined: May 2018
Posts: 7
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sl500 2001 R129
hello phil.
you need to take out the climate control unit ans see if its connect properly. for me that was the problem.
here is example how to remove the climate unit.
its the same idea
you need to take out the climate control unit ans see if its connect properly. for me that was the problem.
here is example how to remove the climate unit.
its the same idea
Last edited by yossiav; Aug 17, 2020 at 11:03 AM.
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