[430Driver]

On my mothers 2000 E430 she's getting warmer air out of the right half of her vents than the very cold air coming from the right side vents.

The dealer says it's indicative of a evaporator core having a leak. Quoted me about $4500.00 to do it.

To me, if it had a leak, then the ac shouldn't be blowing cold AT ALL. I was thinking more along the lines of it bleeding outside air in on that side, or air from the heater core from a door that's not fully closing. The left and right side are just fighting it out now.

I pulled the DTC's from the Climate Controls' LCD readout (this was the day after the dealer had the car).

B1234 - Sun sensor (B32)
B1416 - Coolant circulation pump (M13)
EFF

:surrender: My 70 yr old mom does chemo every other week, this is Texas, she 'gots to have' her AC. Right now she's driving my 01 E430 while I try to get this handled.

Any knowledgable help would be appreciated.

 

[rnettleship]

Is the cold side "Real" cold or is one side hot and other cool? Mine was like that and all it needed was a top off of refrigerant. Check the sticky's for "Duo valve". This valve controls the coolant going to each side of the heater core. It's possible that one side is stuck and keeping the heater core hot all the time, even when AC is on.

I've never done the job but the DIY looks simple.

http://www.benzworld.org/forums/w210-e-class/1350793-duovalve-removal-cleaning.html

 

[Plutoe]

Appreciate the seriousness of the matter. You recovered about a third of the info with the faults. Now go back to the stickies and run the actual value test. Thats the data generated by all the AC sensors on the car. Stop at number 8. Report the data and I am sure you will get assistance.

The faults you have recovered, sun sensor impacts fan speed in relationship to the inside car temp and radiance of the sun. The coolant circulation pump impacts heating the car after the engine has stopped and you selected the recirculate button on the AC control.

Non of your faults relate to the loss of cooling on one side. Good luck

 

[430Driver]

The other side is COLD. I saw the DIY about the DuoValve and am keeping that in mind. It seems more like the left side is bleeding outside air in more than the heater being stuck on. It feels like outside ambient air (hot during the day/cooler at night). Although this could just be the left and right side of the car battling, with the AC more effective after the sun goes down.

 

[eric242340]

Top up the refrigerent at this stage and all should come back to normal.

 

[430Driver]

Appreciate the seriousness of the matter. You recovered about a third of the info with the faults. Now go back to the stickies and run the actual value test. Thats the data generated by all the AC sensors on the car. Stop at number 8. Report the data and I am sure you will get assistance.

How do you run the Actual Value Test? I'm not seeing that, or do you need some sort of scanner?

 

[yeldogt]

My car had this a few weeks ago. Dealer told me that it was common for the right side to be colder than the left when the system was low on refrigerant.

I was thinking it was the Duo-valve and wanted this fixed before the warranty ran out - the difference in the temps was not all that great. Sure enough -- leak at one of the sensors.


A quick check on the duo valve: Put the system on Low -- EC for economy -- and low fan speed -- feel the air. The air should not be heated. Obviously do this with a hot running engine.

 

[Plutoe]

Forget the Duo valve, that's all black magic, the faults did not indicate that was a problem. You will run your tail ragged with that type of stuff. To get the "actual value data" do the following.

Start the car and let it warm up, press the AC auto button, set both sides to 72 degrees, then press REST for at least five seconds----The left display will show a number 1 and the incar temp-----Now press the auto button and number 2 with data will come up----Press the auto button until you have gotten to number 8-----------To exit the program press REST.

Remember to write down the number and corresponding data before you exit the program. Good luck!!

 

[Check Codes]

How do you run the Actual Value Test? I'm not seeing that, or do you need some sort of scanner?

This is in the stickies, although eclassbenz is reworking the pages so the link in the stickies isn't working properly.

Anyway, this is a more complete explanation of the process. Good luck.

Air Conditioning Diagnosis | EClassBenz.com

 

[mbvis]

>>B1416 - Coolant circulation pump (M13)
Maybe the dealer saw that B1416 then quoted $4500.

I had left warm, right cold problem before. "Servicing" the duovalve following the stickies did not help. The values of sensor#3, #4 were still way off from each other; their difference was as much as 15. I think Matt L once said that #3, #4 should read about 2 or 3 from each other when duovalve worked. Anyway, I charged a little more refrigerant into the AC, putting the can upside down. On the gauge, there was a blue zone for filled pressure, I went for the border line between blue and yellow. Both vent sides blew cold right after I did that. Sensor #7 fluctuated between 15-17 at idle. In my other car, sensor#7 reads 15 but the AC worked perfectly.

 

[fabbrisd1]

A full refridgerant eva+fill is about $80 at a competnant auto air con service shop, that is the best way to go, the evac will detect any major leaks.

Keep the beat !

 

[430Driver]

So yesterday I delved into this a little further. I also was pretty sure it was just low freon. If it was a leak it wouldn't blow cool on either side. Pulled a vacuum on it (-30) and then went to lunch, came back and it was still there a hour and a half later... so much for there being a "leak". I'll drive it for the next couple of weeks and make sure it's fine, fix a few other little niggles while I have it.

Recharged the system and it's working perfectly fine. The stealership is going to HEAR about this. Lets see, 70 yr old widower, with cancer, on a meager state pension and the mechanic was lying through his teeth on what it needed. What a despicable cretin. It also didn't need a flex disc, lower control arm bushings or motor mounts like he was saying. About the only thing he got right was the rear trans seal but then he missed a valve cover leak.
I suspect he will be looking for a job shortly.

As the bill would've been over 7K on everything he said it "needed" that would essentially equate to felony theft in my book.

Thanks for all the suggestions. I'm way too rusty these days.

 

[430Driver]

After several weeks and now some serious Texas Heat it is all fine with just the freon top up. Thanks to everyone for the suggestions and patience. Saved my Mom a ton o money just listening to my instincts that something was off with the "diagnostic" and doing some digging here. I guess I let my doubts and the complicated duct work in the merc put me off.

 

[nugent]

...It also didn't need a flex disc, lower control arm bushings or motor mounts like he was saying.

As the bill would've been over 7K on everything he said it "needed", I suspect he will be looking AT A PROMOTION shortly.

Fixed that for ya.

 

[Bcjacobson]

I found this reply forum when I was having the same type of issue - hot on the left side and cold on the right side. Climate control for driver and passenger did not work. I ended up taking the front console off, then the glove box off in order to get to the air mixer control behind the glove box. I finally ordered a new Stepper Motor (small black motor) to fix this. While waiting for the stepper motor to arrive, I was able to manually move the control arm to hot or cold as needed. The stepper motor drives the gears to the air mixer from the control panel.

 

[mrboca]

I found this reply forum when I was having the same type of issue - hot on the left side and cold on the right side. Climate control for driver and passenger did not work. I ended up taking the front console off, then the glove box off in order to get to the air mixer control behind the glove box. I finally ordered a new Stepper Motor (small black motor) to fix this. While waiting for the stepper motor to arrive, I was able to manually move the control arm to hot or cold as needed. The stepper motor drives the gears to the air mixer from the control panel.

No idea what your car's model year and model is, for w210, the airflow direction and mixing is handled by vacuum actuators, with the exception of diversion of airflow through charcoal filters, and this does nothing to the left/right air temperature difference.

 

[Bcjacobson]

No idea what your car's model year and model is, for w210, the airflow direction and mixing is handled by vacuum actuators, with the exception of diversion of airflow through charcoal filters, and this does nothing to the left/right air temperature difference.

This was for my son's older 2002 C240. Your right, there is quite a difference year by year and for the different models. Wanted to put this out here so that anyone with a 2002 would have some info that may help.

 

[mrboca]

Yeah, for W203 there are 6 motors that control the airflow. The good thing about it that it does not have a duovalve. The heater core is always hot, temperature control requires intricate control of blend flaps with stepper motors.