1999 W210 E320 A/C problems - PeachParts Mercedes-Benz Forum

Rahulio1989300E · #1 05-28-2006, 01:11 AM

Hello everyone,

I am having some trouble with an E320. (~57,000 miles)

Here is a short history,
About 1 year ago, the driver's side speaker in the dash quit. I ignored it since it seemed very hard to remove the speaker from the dash.

Then, shortly after that (1 month maybe), The driver's side a/c vent only blew warm to hot air, even though, the system was set for cold air. All other vents worked fine. Took it in the Park Place for diagnostics, suspected that one of the ac doors in the dash stopped working. Made sense to me, but my father and I could not justify the $1300 price tag in labor alone.

Before we could get a second opinion, I had to leave for college, and my father kinda forgot about it.

So, now, as of about 1 week ago, the entire ac system is stuck in economy mode. The EC button below the lcd screen always has its red led on no matter what, pushing it does not make it go away.

Every vent now blows air in similar the the temp outside the car, as the EC mode does not allow the AC compressor to work. So no more cooling.

I am in a bit of a Mercedes-Benz crisis, my 1989 300E had developed a coolant leak which the source is still to be determined... and now my mom's car is acting up even more.

I want to really get the ac going for my mom, its hitting 90 to 100 now in Texas, and windows down is not that helpful...

Please give me suggestions and if you can, instructions on how to access the dashboard components. I am constantly learning about these cars, I have done a lot of work on my 300E by myself, I know that 10 years of tech has made everything more complex, but I am willing to try. If I cant do it, it will go to our trustworthy Mercedes-Benz indy shop.

Once fixed, I think this car is going to be sold... sad to see it go, but it has had problems...

Thank You,
-Rahul

Matt L · #2 05-28-2006, 10:21 AM

Your climate-control pushbutton unit gives you lots of information. Search for N22 here, and learn how to extract the current sensor values and any trouble codes. Do so, then get back to us.

sokoloff · #3 05-28-2006, 10:25 AM

Had the same problem a few years ago. See my fix here - 210 chassis climate control problem

Some say you only need to recharge the system and maybe add some dye to find the leak. MB says you always must replace the sensor and reprogram the unit as indicated in my thread. A common leak area is the short one foot hose from the receiver/drier to the compressor. Look for oily residue at the R/D end.

BTW, I never had to add any R134 to mine, but I'm now noticing that the driver's side is a little warmer than the passenger side and there might be a little leak at the hose I indicated above. I suspect I'm now due for a recharge.

Len

Matt L · #4 05-28-2006, 10:39 AM

P2 +16 is "Refridgerant fill level check switched off." I doubt that it helped you (but wouldn't hurt). The evaporator temperature sensor was your only problem.

Rahulio1989300E · #5 05-29-2006, 01:02 AM

Wow, thanks for the tips, I will inspect the hoses in the morning, could you please tell me the exact name of the part you replaced under the dash on the drivers side?

Again, thanks a lot!

Matt L · #6 05-29-2006, 08:36 AM

That was his evaporator temperature sensor. While you might want to replace it as a prophylactic, you should check the current sensor values to see if it's the problem first.

Rahulio1989300E · #7 06-03-2006, 04:07 PM

Okay, I got around to doing the tests.

The Fault Codes are:
Eb1227
Eb1241
E FF
E

The Actual Values are:
1 85
2 82
3 87
4 85
5 87
6 85
7 05
8 84
9 27
10 3.2
11 2.3
12 4.2
20 3.2
21 32
22 00
23 32
24 11.3 to 11.4 fluctuating raplidly
40 164
41 32
42 104
43 136

HELP!

Matt L · #8 06-04-2006, 09:56 AM

B1227: Outside temperature indicator temperature sensor (B14)
B1241: Refridgerant fill

If the compressor wasn't running, the fill is probably fine at 5. Try adding 16 to the P2 version code.

Rahulio1989300E · #9 06-06-2006, 01:06 AM

how do i do that?

Matt L · #10 06-06-2006, 01:14 PM

Going from memory here, so I hope it's right:

Engine off, key in position 2

Left temperature setting HIGH
Right temperature setting LOW

Key to position 0

Press and hold REST. While holding REST, turn key to position 2. The left side of the display should change to read P1, and some number will appear on the right.

Pres ECON to advance the left side to P2. Write down the number on the right.

IMPORTANT: Break this number down into powers of two. If it already contains the value 16, adding 16 to it will not have the desired result, and there's nothing to do. Just turn the key back to position 0 to end the version coding menu. Otherwise:

Press the right-side temperature up button (red arrow) until you add 16 to this number. Press and hold the REST button >1 second.

Key to position 0 ends the sequence, and returns N22 to normal. Key to position 2 and reset the temperatures to 72 by pressing up and down simultaneousely on each side.

Rahulio1989300E · #11 06-07-2006, 01:31 AM

Hello,

Just went into the garage to do this coding...

Bizzare stuff...

Okay, here is what I did...

1) ENGINE OFF, turn key to position 2
2) Left setting on HIGH
3) Right setting on LOW
4) Key to position 0
5) Press and hold REST, turn key to postion 2
6) P1 value showed up, but the entire lcd display was flicking, I mean the insturment cluster lcd was fine, the the ac units was flickering, like all the line were partially lit. It was really hard to tell which numbers were showing on the right.

But, I think I got P1 as 120 to begin with, I am lost about the powers thing, do you mean to see if 120 is a power of 2?
2, 4, 8, 16, 32, 64, 128, 256....... 120 is not, but is divisible by 2 but not 16.... please explain...

I upped the value by pushing the right red arrow 16 times.

7) Hold down rest, switch off ignition.

Then I turned back to 2 and turned the ac on, all was normal, EC light is gone, but it is 12:30 now, I did not want to start engine to test. I left a note to my mom not to try and use the ac despite the now unlit EC light, just incase I did not do something right...

Also,
I tried the test where you hold the 2 auto buttons for 10 second, i did this while the car was in ignition position 2, but the fans that are supposed to come on did not... please advise....

Thanks for bearing with me...

Rahulio1989300E · #12 06-07-2006, 01:33 AM

Wait a min, by powers of 2 do you mean...

120 / 2 = 60 ............. NOT 16!
60 / 2 = 30 ............... NOT 16!
30 / 2 = 15 ............. NOT 16!

It that what you meant by break it down into powers of 2?

Matt L · #13 06-07-2006, 10:17 AM

Any rational integer can be expressed uniquely as a sum of distinct powers of two. That's the same as converting to base-two notation.

BE SURE that you're setting P2 and not P1.

Assuming 160 for P2, 160 = 128 + 32 = 2^7 + 2^5. 16 is not present.

Rahulio1989300E · #14 06-07-2006, 10:29 PM

Hello,

Okay, I did the change last night, I tested the car today, after doing to + 16 to P2, the EC light turned off.

The ac ran well on the way to work. but on the way back, about 10 minutes into the trip, the ec light suddenly came on and the air became warm again....

I will try to diagnostic test again and post the values...

Matt L · #15 06-07-2006, 10:49 PM

I missed the question about the auxiliary fan activation through the pushbutton control unit N22.

The diagnostic manual says to hold both buttons for >10 seconds. It takes at least 12 seconds for my N22 to activate the fans.

I don't know the failure mode of the fan in your car, as the controller is different than mine, but on mine, if the current draw is not correct (too high or too low), the fans will "kick" about once every six or eight seconds but not quite start. I would not be surprised if the failure mode in yours is either exactly the same or completely different, but it doesn't hurt to go watch them. If the fans don't run when they are needed, the high side pressure and temperature will skyrocket.