Vic_E55_2001

My AC works very good, fast, cold, not to noisy.... on the right side.
On the left side it `s not blowing very cold air... heater working just fine and air flow seems to be working ok.

I know that this is not evaporator and/or drier problem because right side as cold as it should.

My question is this:
Do anybody have schematics for 2001 E class?
Where I can find one?

Please anybody help me.

MBTech21

Sounds like the eavaporator temp. sensor- very common, and it is a dual sensor, reads both sides- it is located on the left side of the heater box in the drivers footwell- has 2 wires hooked to it, and just pushs in to the box. Your local dealer would stock this (if that tells you anything).

Vic_E55_2001

I assume there is 2 sensors there? one for each side? How I can diagnose the sensor? Thanks for your help.


and if it is just one could the problem be in vacuum actuator?

MBTech21

Two sensors built into one- when inside the box, they are actually seperated from each other. It could be a vacuum issue, but I doubt it- if the temp changes, just not enough, sounds like the sensor.
As to how you would check it- good question, we read it on the SDS machine and one side will have a funky reading- no codes, just a reading that is off. Never seen an ohm check or anything for this condition.
I quess your choice is- pay to have it checked, or buy a sensor and take a leap of faith. I guess that depends on what the relative costs are in your area.

Vic_E55_2001

Thank you so much. I think I will buy a sensor and give it a try. Do you have a part number for me or should I just ask for evaporator temp. sensor? Anyway I`ll keep this tread updated.

MBTech21

I got this too late to check the number for you- just ask for that- they will know, believe me!!

Vic_E55_2001

I asked, they didn`t find it.... is this one what I need?




I also tried to read actual values from this chart, not sure what I`m looking for but #5 shows about right temp... close to ambient on startup and 20 degree lower in 5 minutes...

MBTech21

Thats it, but sounds like it is reading right- my next step would be the heater core temp sensor (behind radio- looks similar and reads the same way- two sensors built into one).

Vic_E55_2001

The one with 3 wires ? I thinks I found it like you said behind the radio.
I tested actual values and two sides shows a little different values.... like 85C
for the left and 90C for the right.

MBTech21

Thats it-the values should be the same- 5 degrees C enough of a difference to feel at the vent. Are you checking this with the AC on? Are you sure the duo valve is working?- its supposed to shut off the water through the heater core when in cooling mode.

Vic_E55_2001

yes, I`m checking with AC on. where the duo valve is located? .... i`m not sure if it is works. how I test it and how I can test heater core temperature sensor?... wow.. too many questions... Thanks man!

MBTech21

The duo valve is in the cowl- it should shut the water off when you request low AC temp. One outlet for each side of the heater core.

To be honest, you should probably take it somewhere and have them check the actual values with an SDS- it shouldn't cost more than an hour's labour, if they tell you its something cheap, no problem, if they tell you something outrageous- get the printout of the actual values and let me have a look at them.

Vic_E55_2001

Heater core temp sensor is fine , I pulled it out and it shows same Ohm, i switched ( so right sensor picking up temp from left side) them and problem still the same. I found duo valves under the hood where aux water pump connected to them and then 2 separate outlets going to the heater core.
I didn`t tested them yet, gonna do it tonight. I would definately take it to the dealer, those guys knows what they do... but money is an issue right now.. and I really enjoy working on my car. Thanks for all your help! I really appreciate it.

Vic_E55_2001

it doesn`t make any sence to me...

Vic_E55_2001

?

MBTech21

Thats the dryer they are talking about- but seeing your car is an 01, it should be way past the VIN break. If I remember correctly back to then, the thinking was that the evaporator was starving for refrigerant- hence a little bigger dryer with better flow.

MBTech21

Duh..if I had read the document- it says production run error- no fluid passage- so no refrigerant was getting through it. This was also around the time the sight glasses were breaking- that was the other change I was thinking of- they changed the dryer and took it out.

Vic_E55_2001

I found this on on another tread:
Originally Posted by lexrex
You didn't put in enough R134a. Whenever you're moderately low, the passenger side will blow cool air and the driver's side will blow warm. You'll probably also hear hissing from the center vents.

Add more R134a until your evap temperature drops below 40 degrees and/or the hissing fades away. (You can watch your evaporator temperature using the climate control diagnostics; see search the forum archives for instructions)

My A/C making exactly that weird hissing noise mentioned in above post.
So... I`m geting my A/C serviced tomorrow at my local dealership. They have 100 bucks special(CHECK AIR CONDITIONING SYSTEM FOR LEAKS AND PROPER OPERATION. INCLUDES UP TO 1LB OF R134 REFRIDGERANT WITH THIS SPECIAL.)

MBTech21

THis hissing is a dead give away it is low. Good Luck!!

Vic_E55_2001

Service advisor just called and they recharged AC. He said that they found a slow leak in the hose from condencer to something, I don`t remember. he quoted $820 for that. I don`t think I would do that since leak is very slow. My AC was working with that hissing noise for at least a year.
He also said that my lower ball joints a shot and I have to replace them.
I kinda suspected something like that. Do you know if ball joints are the same on all W210? or AMG has different ball joints?

Vic_E55_2001

........

MBTech21

I think they are all the same.

Vic_E55_2001

I was there to pickup my car and guess what- AC is empty, they evacuated all refrigerant and left it empty. Now they want to replace condenser to drier hose and drier, $820... that is insane, AC was working and that was very slow leak. I`m so disappointed... The fact that I own AMG doesn`t mean I have shidload of money.

Musikmann

That is horrible!

I just had some similar dignostics done (another thread on this forum) and they are quoting me over $1700 - however this is for condenser, drier, that same hose and about $200 is for a possibly needed auxillary fan for the radiator. Backing that out, they therefore want $1500 with NO guanantee that those are the source - it might cost me another $2800 if they later determine the evaporator core needs to be replaced. Labor alone is 19 hours at $94 per hour

Ha! The only positive comment I can make here is that they re-charged the refrigerant during the diagnosis and left it in there, so I temporarily have an air conditioned car and they quickly washed it ($130).

Good Luck,
Musikmann

Vic_E55_2001

I want them just to recharge the system, nothing else. I caller another MB dealer and they quoted me $390 for hose, drier and recharge.
Not $820. Slow leak could be recharged once a year for ~$100... I really prefer that way. I might sell this car in couple of years and buy a lexus or something like that, I just don`t make enough to support such a lovely car as AMG. it is 5 years old car and don`t have to be as good as new.
In two years owning this marvel of German engeniring I spent more money fixing it that I can lease brand new one. and I do mostly all the maintenance myself.