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Your #7 sensor measures the refrigerant pressure. It's showing zero. Based on the conflict between the sensor and your R134a gauge, I'd say you have a malfunctioning refrigerant pressure sensor.
The error codes are inconsequential.
Thanks for the updates. Based on the R->L temperature differential and lowish pressures, I think you need a recharge. None of the error codes show anything serious.
Seth, the code on #7 states no charge. I suspect you need a recharge, although it could be a malfunctioning pressure sensor. Unless your EC light is stuck on, recharge is most likely.
No hissing sound from the vents but I'll add some 134a with UV dye just in case and report back.
Thank you for the help,
I have a 1999 CLK 430 and it has air for about 1 minute then the compressor shuts down the low side runs @41 psi I dont know where the high side connect is?
1-86
2-118
3-86
4-84
5-158
6-194
7-7
8-95
Trouble code
E FF
Hi, I have same problem as paulmcconnon below, a/c working fine but (very)heated air simultaneously coming from outboard vents.
Didn't see an answer to his question?
ps prebuying beer
I talked to my mechanic he replaced temp sensor but connector that plugs into it broke apart when he removed old drier. I cut the connector from my parts car for him to use. He soldered it on but it was a bit broken also. Any option other than replacing wiring harness?
the last number is a one and we did a system recharge and found it to be at full pressure , hwo would i go about trying to get to the bottom if this if it is a leak?
1-76
2-100
3-93
4-92
5-49
6-154
7-13
8-122
Codes Eb1231, Eb1430
A/C blows icy air from all dash vents most of the time, infrequently outboard vents switch to heated (very hot) air while center vents still blow icy ( with blue button depressed.) This condition persists until vehicle is switched off for a period of time.
I have tried the flap diagnostics and all flaps actuate, though it seems they are all “on” when the indicator reads “off” and vice versa.
Any help would be appreciated!
Sensor Codes: 1- 76, 2- 82, 3- 58, 4 -57, 5- 51, 6 – 186, 7- 08, 8 – 94
Error Codes – E61-416 , E61 – 234, E61 – 416, E -FF
Hi
my dad's mercedes has a wierd ac problem where sometimes all the vent blow nice and cold except the drivers side near the door and the drivers side rear, those blow hot
the sensor values when working properly are
1 – 22
2 – 29
3 – 03
4 – 03
5 – 08
6 – 77
7 – 14
8 – 54
the sensor values when its acting up are
1 – 26
2 – 20
3 – 59
4 – 23
5 – 10
6 – 81
7 – 14
8 – 59
the trouble codes in it are
b1231
b1234
b1419
b1459
i would GREATLY appreciate this, thank you so much for being here
-joe
Blake: Thanks for reply. I will try to clean left duovalve. Yes, the EC light is stuck on and the prior owner recharged the A/C and it did not hold. Before I contacted you I had cleared the codes and they came back as noted. My mechanic wants to replace the compressor, but I am with you that I want to determine other issues, etc first. What kind of priorities should I have him work under? I do appreciate this very much. You are terrific!
The system won't accept any gas. There's too much pressure at the charging valve that no 134 will go in. (Yeah I had the low side port) I tried at idle and also with engine revved a bit. Do I possibly have a restriction somewhere in the system? Expansion valve? Receiver/dryer? Ughhhh…. Thanks again !
Hello,
Im hoping you can help me here and I will gladly buy you a beer or two
My 1998 E320 4matic A/C no longer blows cold. (It did last year through only one vent, so I had it topped off and it lasted the summer, but now its not cold at all!)
Here are the values for the sensors 1-8 :
1- 24
2- 20
3- 39
4- 40
5-24
6- 85
7- 00
8- 32
This showed up under the “error codes” section
Eb1 227
E FF
Eb1 234
E
Please advise,
Thanks!
John
Paul, did you get a fix? I have the same problem.
Thanks.
Ok! We are back in business! Cleared all of the error codes as you suggested and we have full AC. No more dreaded EC light and solid pressure in the 7 – 11 range. Thanks for all of your help. Beer is on the way!!!!
kevin
1-76
2-75
3-80
4-80
5-78
6-18
7-06
8-87
error codes b1 234,235,416,419,424,241,ff
Will buy Beer!- Thanks
Hey there! Need some help with my AC and I really appreciate it! AC stopped working last week on a 92 degree day. Ran the diagnostics and it was showing an error code EB1 459. Changed the Evaporator Temp Sensor and cabin filters. Cleared the code and it has not returned. Worked great for several days. Last night it stopped blowing cold air again. This morning with engine cold I let it idle for three minutes then performed the diagnostics again (the Compressor never kicked in during the test). the codes are as follows- Thermometer in garage showed 75deg.
1- 78
2- 76
3- 84
4- 83
5- 71
6- 150
7- 6
8- 120
No error codes
Is number 7 low for ambient air of 75? Also I have seen number 8 get as high as 159 – is this normal? Your thoughts are greatly appreciated!!!
Bob
Hey there,
I have a mercedes 1999 E320. I have an air conditioning problem. In the morning when I start the car and I turn on the air condtinar on low level my air conditinar is working perfectly after 10-12 mins the air compressor clutch is kicking off and doest come back on, unless I turn off the car for a while then start the car up again.
Here are the readings for the sensors the first time:
1-80
2-91
3-49
4-85
5-164
6-186
7-11
8-120
No error code came up.
Thx
Andy,
Two problems:
1. You have a faulty evaporator temperature sensor, which is why your A/C quits working after 10-12 minutes. That sensor needs to be replaced.
2. Based on the temperature values above, it looks like your right duovalve is stuck open. It needs to be cleaned. The duovalve controls the heat. You may notice that the vents on the right are considerably warmer than the left. See my responses below for information on how to clean the duovalve.
Bob,
Is your EC light on? If the light is off and the compressor isn't turning on, I recommend that you use a multimeter to check the compressor clutch leads for voltage to determine whether the climate control computer is signaling the compressor to engage. If it is, you have a faulty compressor. If not, it could be low refrigerant charge or a problem with your climate control.
You have an error code indicating that you need a recharge.
Is your EC light on? If so, try this to override it (sometimes the low refrigerant error code is caused by a faulty sensor):
1. Switch the ignition on (position 2).
2. Set the left temperature to 'HI' and the right temperature to 'LO'.
3. Switch the ignition off.
4. While holding the 'REST' button, switch the ignition on (position 2). On the left side, 'P1' will flash and on the right side, a code will be displayed.
5. Press the 'EC' button twice so that the left side flashes 'P2'.
6. Using the right side red temperature increase button, add 16 to the value.
7. Press the 'EC button again to store the updated code.
8. Turn the ignition off.
If the EC light has been off (or is now overridden), and you're not getting cool air, try this to clear the error codes.
1. Go into the error code mode as described in step 2 of the instructions at the top of the page.
2. Press and hold both AUTO buttons simultaneously for at least five seconds. The screen will switch to “e FF”
3. Shut the ignition off.
If that doesn't work, you probably need a recharge.
Looks like the system's empty again. You have a leak somewhere. The most common leak points are the receiver-drier canister ($), condenser ($$) and the A/C compressor ($$). Evaporator leaks ($$$) can happen but are pretty rare.
Joe,
Your dad's car has a stuck duovalve on the left side. The duovalve needs to be cleaned. The duovalve controls the heater. That is why the vents on the left are blowing hot air. See the instructions here for cleaning it:
http://www.benzworld.org/forums/w210-e-class/13...
Can you describe the problem some more? Are you having a problem with temperature or airflow?
Your air conditioner appears to be working. According to the sensors, the air isn't quite as cold as it should be, but it never is when the car is parked. More information would be appreciated.
Thank you for the beer.
Looks like your heater is intermittently stuck on. The usual culprit on the E-class is the duovalve, which controls the heater. I suspect that yours needs to be cleaned. The instructions for cleaning it on the E-class are here:
http://www.benzworld.org/forums/w210-e-class/13...
I am less familiar with the W140 S-class, and can't tell you exactly where you would find the duovalve. I would expect to find it behind the firewall. You should be able to find it by tracing the heater hoses running into it.
Otherwise, everything else looks pretty good. Your evaporator temp is under 50 degrees and you have good refrigerant pressures.
*** UPDATE: Here's a possible alternative diagnosis. The blue button in the center forces those vents to blow cold air. It's possible that, rather than a problem with the duovalve, your cabin temperature sensor has gone nuts. In that case, the computer could be blowing hot air to warm up what it thinks is a frigid interior. The number you sent don't show any evidence of that being the case. But your problem is intermittent and those numbers reflect just a snapshot at a single point in time. You can override the cabin temp sensor by turning the temp on both sides all the way down to LO. If you still get hot air when both sides are set to LO, you can rule out the cabin temp sensor as being the problem.
John, the problem is your evaporator temperature sensor. Replace it and you'll be back in business. See here for DIY instructions:
http://www.mbworld.org/forums/e-class-w210/1539...
Paul,
Somehow I missed your question when you originally posted it. Sorry about that.
Your air conditioner is working well and you have good refrigerant pressures. I think you have a problem with your duovalve. The duovalve controls the heater. Sometimes one side gets stuck in the on position, which causes the vents on that side to blow hot air. The good news is that in most cases, you can solve the problem by taking it apart and cleaning it. See here for instructions on how to clean the duovalve:
http://www.benzworld.org/forums/w210-e-class/13...
Your fan quit blowing completely? Does the AC panel work? Have you checked all the fuses? If the AC panel works and the fuses are all good (make sure you check all of them), your blower motor regulator probably burned out. What year is your car? If '96-'99, you can find instructions for replacing it here:
http://www.mbworld.org/forums/e-class-w210/1539...
Kevin,
It may be as simple as a recharge, but I've gotta admit I'm not convinced of that. Your refrigerant pressures (~180 psi) look stellar compared to the air temperature that you're getting (80-90 degrees). I'm leaning toward a more obscure explanation — a clogged evaporator expansion valve. The numbers only tell me so much; I really can't be sure.
The hissing noise indicates a relatively insufficient amount of refrigerant entering the evaporator. That occurs both when you're low on refrigerant and when the expansion valve clogs. The two conditions (low refrigerant charge and clogged expansion valve) are virtually indistinguishable, save for the refrigerant pressure (low in the former, high in the latter).
1234 is the sun sensor, which is harmless. 1416/17 are the duovalve codes.
What to do next? Your call. You could go one of two ways:
Option 1 – Assume you need a recharge: Recharge and hope it's not your expansion valve. In this case I think it's important to do it properly (no DIY): Evacuate all the refrigerant, measure it, and replace with 1kg R134a. If it still doesn't work proceed to…
Option 2 – Assume it's the expansion valve: Replace the expansion valve and recharge. Technically the receiver-drier should be replaced as well since the system has been opened.
If you start with option 1, and you're wrong, you've wasted the cost of a recharge.
If you start with option 2, and you're wrong, you've wasted the cost of the expansion valve (and possibly receiver-drier).
What temperature settings did you use? How warm was it outside? Sensor #2 reads 55 degrees, which is consistent with the 58 degree reading on #8.
If the outside ambient temp was truly in the 50-70 range, you have a faulty evaporator temperature sensor.
Is your EC light on? You have a code for your compressor clutch. I suspect your compressor is not engaging. Try clearing the codes by going into the code diagnostic mode (step 2 above), pressing both AUTO buttons simultaneously for at least 5 seconds, and shutting the ignition off.
If it still doesn't work, the next step is to check the voltage on the compressor clutch leads. If there's no voltage, it could be as simple as a recharge. (The compressor has a fail-safe mode that prevents it from engaging if you're low on refrigerant.)
Mo,
It looks like you cycled through the list backwards (#1->#43->#42->…) I need sensor values #1 through #8. Also, a description of the problem in your own words would be helpful.
Hey Blake,
Okay, so what would you do to diagnose the leak? I guess you would not recommend filling the system with a sealer than filling it with refridgerent? Also what are your thoughts on the “canadian tire” DIY refill kits?
Thanks,
John
EC light is out. Compressor spinning.
Hi Blake,
like many, I have a new 1999 E320 (only 75k mi!). It seems like I'm always adjusting the climate control. The codes read:
1- 76
2- 55 (matches outside temp)
3,4- 103
5 120
6-184
7- ranges from 3 to 12 (what's normal?)
8 58
E FF
My question is at what point do I know I need a recharge? I think the system is working, but it seems like it blows cold air when I don't expect it, and warm when I think it should be cooler.
Thanks for the help.
i will do that, thank you so much
if it were stuck, would it still only do it sometimes? just wondering, i
really apreaciate all the help, may God bless you, you are very kind for
doing this for everyone
Hi,
I just donated $ 10 to your account.
Thanks a lot again, it was a very useful info.
Got a sensor from my parts car and my 1999 works impeccable.
Will recommend your forum input to others.
Alex
Hi there Blake I loaned my 97 E320 to my uncle while I was in Iraq and when i got back its been nothing but problems, I am living in Florida and its summer now I need to get this AC fixed its unbearable.
OK my sensor values are as follows
1- 53
2- 39
3- 45
4- 44
5- 42
6- 86
7- 01
8- 43
and my error codes are as follows
E61 234
E61 459
E61 241
I am going to buy some refridgerant and some sealer and run those through to see if I can get my pressure up. Also my AC fans in the front of the car will not turn on at all I am suspecting a sensor problem please let me know what you find its much appreciated and I would love to buy ya a beer for the help.
R/S
Sweaty Marine
Okay, my EC light was on and I did the first part of your instruction and the EC light is now off, but no air. Are you saying to go to Part 2- collect trouble codes again.
thanks!
One update to my post below- the symptom I notice is that when I first start driving the car, the AC blows cold even if the inside temperature gets below the setpoint (usually 72 for me). Then after about 10 or 15 minutes, it starts blowing warm. Makes me wonder if the internal temperature sensor isn't getting enough airflow.
I suppose my problems are trivial compared to most on this page, but I expected better from my new MB.
I have this intermittant issue with my climate control unit recirc light blinking and the system shutting off and back on. No faults… Would you comment on the values below for anything obvious. 90 degrees today and running the ac for 20 minutes.
1 – 26
2 – 36
3 – 10
4 – 11
5 – 13
6 – 102
7 – 14
8 – 56
Thanks in advance.
Sensor values and fault codes from a 98 E55
1 – 23
2 – 25
3 – 23
4 – 24
5 – 38
6 – 87
7 – 00
8 – 32
Codes – B1416 , B1227 , B1231 , B1459 , B1424
So it looks like I have no gas, are any of the error codes caused by this and how do I reset them if I regas the system?
TIA! Andy
Hi Blake,
I have a 97 E320 with 40k miles, AC doesn't work, compressor doesn't engage & EC light stuck.
Sensor Readings;
1 — 34, 2 — 27, 3 — 22, 4 — 22, 5 — 21, 6 — 78, 7 — 06, 8 — 28
Error Codes;
Eb1 419, Eb1 419 (with small fan sign in middle), Eb1 241 (fan sign in middle)
I had rest the codes & now error codes are;
Eb1 419, Eb1 419 (with small fan sign in middle)
Still – AC doesn't work, compressor doesn't engage, but EC light is not stuck any more.
Little background:
Had water pump replaced recently, but AC wasn't working before either.
Bought this car new in 97, AC always gave problems, last yr had R134a refilled, after that in worm temp. AC would give hot air, when I used to change from Lo to higher temp, only then I used to get cold Air. Mechanic said he had put too much gas and took some out, problem was solved but AC wasn't strong. Finally, after few months cooling was gone. Mechanic checked and he says gas is enough, car has bad compressor “code 419”
Looking at the error codes do you think its the compressor ?
Any help will be greatly appreciated.
Hi there, My ac has died and I stumbled upon your site – hoping you can help me. A Texas summer is fast approaching. Happy to donate – Thanks in advance!
1 – 85
2 – 81
3 – 81
4 – 80
5 – 70
6 – 113
7 – 9
8 – 95
Error codes: Eb1 “little fan symbol” 230
and E FF
Once again Thanks for any help!
I have a 2000 E430 with A/C problems. The air is cool at first then warms on the side vents. I am also having a hissing sound. There is plenty of air flow from the vents. I found trouble codes b1234, b1416 and FF. The outside temp was 71 when checking the sensors. Could you also explain how to clear the trouble codes. Thanks for any help.
1. 76
2. 73
3. 39
4. 39
5. 35
6. 168
7. 13
8. 107-114
Hi blake, I have a 99 clk 320 i hope that the reading are the same, please help.
1- 86
2- 140
3- 83
4- 84
5- 155
6- 201
7- 6
8- 111
Error Codes- Eb1 232, Eb1 403.
Thank you
Hi, little background on my a/c problems, My a/c stopped working the end of last summer, actually the same day my left side motor mount let go. I brought it to an indy to get both issues taken care of, he said refrigerant was full, must be he control unit, I replaced the control unit, and still nothing.. here are my readings..
1 98
2 69
3 93
4 95
5 120
6 135
7 5
8 76
and the trouble codes are
eb1 e61 ? rither or..
226
232
419
421
E FF
A cold one will come you way….
Blake:
Thanks for the great web site.
I have 1998 E320 that blows warm air out of the LH vents/Cold out of the right.
Here are my sensor readings:
1=103
2=100
3=93
4=80
5=95
6=190
7=14
8=139
OAT-83 deg F
Trouble codes:
E61 227
E61 231
E61 234
E61 235
E FF
Vent outlet temps:
LH Vent 92
LH Center Vent 92
RH Center Vent 64
RH Vent 73
EC light off
Duovalve cleaned twice.
Thanks for your assistance.
bob
David- Please help with my 98' E300!? I drive this thing everywhere and I have went 3 weeks without air. Here are the codes:
VALUES
1-32
2-35
3-72
4-71
5-34
6-83
7-24
8-65
CODES
E61 R227
E61 231
E61 232
E61 234
E61 235
E FF
Any help would be greatly appreciated!!