ssfisher

Hello, kinda new to my s500 w220. Its a 2001 year. My ac blows hot air only on drivers side vents and cold on passenger side. I get a code KLA 1417 on the climate control head. I have changed out my dual valve with on from a junkyard car, same issue no change. Ive changed the outside sun sensor again from junkyard car, same issue no change. Ive checked the inside temp sensor and it checks good via continuity. If i remove the larger solenoid connector at the dual valve while car is running and check voltage i have 2.89 volts at the plug. If i put my hands on the two smaller solenoids on the dual valve while the car is running the solenoid closest to the firewall is hot and the other one is luke warm. Ive been trying to fix this for months with no success. I hope ive posted this in the right place. Thanks for any help.
Fish

engindin

Have you checked 134a level? Mine was low when car blow hot on rear.

ssfisher

Yes, just filled it with the ac machine at work

ssfisher

Also as soon as i clear the code on the climate control head it comes back immediately

ssfisher

If i post all of the nr. Numbers from the ac head would anyone be able to make sense of the info for me? Ive read different forums on this site about this similar issue for a few hours and i still cant find a fix

DrDoe

What were the temperature settings when you get hot air? Do you get cold air when you set you're temperature setting to LO? What about HI? By changing your temperature settings you can eliminate the sensor issue. Good luck.

ssfisher

It doesn't matter where the settings are. Automatic or hi or low or manual. It is always blowing hot air. I cant ever feel cold air on the drivers side. Even if im in the door flapper check mode and i move the flappers from close to open or 0% to 100%

wallyp

Is the tiny red light ON in the AC button? Light ON means that the AC is OFF.

If the light is off with the engine running and the AC on, carefully feel the lines from the AC compressor (stay away from moving and hot parts!). One line should be cold, the other very hot (caution!). If both lines are the same temperature, the refrigeration system is not working. If one line is cold, the refrigeration system is working, and the problem is in the HVAC control system or box.

EDIT: Sorry - just realized that you get cold on one side, hot on the other - you can ignore this answer!

ssfisher

Yea, all that stuff is normal

ssfisher

Any other thoughts? I could really use some ideas or things to check

DrDoe

My rear right passenger side blow hot air on all temperature settings except for LO. Front left, front right and rear left work fine. I tried to locate a sensor but couldn't find one.
Today I found out that I don't have that problem anymore. DTC reset with OBDII reader is the only thing that did to the car that might have an effect. It worth a try...

ssfisher

I did a reset with my scanner and also disconnected the battery for 30 minutes.

ssfisher

I think im supposed to have 12 volts at the large solenoid on the dual valve but i only have 2.8 volts. Im not sure where that voltage is supposed to come from? The left SAM?

kraut56

The "large" solenoid on the duo-valve is the recirculation pump.
The the two "small" solenoids are for the left and right side water valves, these should see the same voltage for on and off.
Not sure if they get powered on for heat, or vice-versa; you can measure that on selection.

Good luck!

wallyp

My S430 does the same sort of thing, but on the passenger side. My wife now just closes the vent, then puts the temp to LOW for that trip. Next day, things are usually back to normal.

As soon as I find my round tuit, I'll see about fixing it - if I can catch the system when it is broken.

ssfisher

Yea the pump i would think should take more than 2.8 volts to run it tho? That voltage never changes regardless of settings

ssfisher

Every vent is closed that pushes hot air. I wish mine went back to normal after the next day but this has been going on for a month now. Its my daily driver

ssfisher

Any other ideas or thoughts? There has got to be someone on this site that know what i should check next. Ive read alot of forums here and ive read some smart replies from people. I live in Denver Colorado so if anyone on here has a shop i could bring it by to scan the star system?

ItalianJoe1

That code shows a left duo valve fault. I'd suggest swapping out that heater valve first, if it's mechanically stuck open it won't matter what you do, it won't stop coolant flow and give you pure cold air.

You may be able to pinch off the heater line going to that duo valve and test my theory, I vaguely remember the hoses being separate when I was in there last on my w215.

ssfisher

I put a different dual valve in and it was the same problem. How much voltage should the resurculating pump have? What opens and closes the dual valve solenoids? Thanks for the help. This is good stuff

ssfisher

Anyone else got any ideas? It sucks having hot air blasting always thru the door.

DrDoe

If I was you I would find someone with STAR system or pay the dealer the diagnostic fee. I think I'm at that point right now with my power trunk issue. I paid the diagnostic fee already and I think I will end up having to pay the dealer to fix it. Sometimes we just can't fix everything on our own.

ssfisher

Im not ready to give up yet. With the info ive posted and voltages i know someone on this forum could tell me to check something i havent checked yet. And if you need more info just ask and i can check whatever. Thanks

DrDoe

Determined. I like you.

I thought about your issue some more and I ran into this pic. Can you swap #18 and #19 to see if the problem change?

My trunk problem: trunk won't raise or lower. The pump gets no signals to tell it to turn on.
I can't see any broken wire and I have to admit that I haven't ohm every wire yet. I can't figure out which wire to ohm.

DrDoe

#18 and #19