W203 air conditioning diagnostic mode (C320/C32 only)
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From: Bloomington, IN
1997 Toyota Tacoma 4x4
W203 air conditioning diagnostic mode (C320/C32 only)
Push "0" and "EC/REST" button simultaneously until display changes (approx. 5 seconds)
I've only included the values that may be of interest to owners
00: Interior temp sensor
01: Interior temp sensor
02: Ambient temp sensor
05: Evaporator temp. sensor
06: Engine coolant temp.
07: refrigerant pressure
08: refrigerant temp.
16: carbon monoxide value
17: nitrogen oxide value
18: dewpoint temp.
21: engine RPM
22: vehicle speed
24: battery voltage (very handy)
I've only included the values that may be of interest to owners
00: Interior temp sensor
01: Interior temp sensor
02: Ambient temp sensor
05: Evaporator temp. sensor
06: Engine coolant temp.
07: refrigerant pressure
08: refrigerant temp.
16: carbon monoxide value
17: nitrogen oxide value
18: dewpoint temp.
21: engine RPM
22: vehicle speed
24: battery voltage (very handy)
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From: Houston,TX-moving to The Woodlands,TX SOON!!!
Toyota Tacoma & Lexus IS250
I don't get it -- you hold the buttons and these codes pop up on the display or what ? or if certain codes pop up there's a prob or what?
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From: Nashua, NH
2008 VW GTI
16: carbon monoxide value
17: nitrogen oxide value
I wonder what it does with these values? Are they cabin readings or outside air readings?
I wonder if the car will shut itself off if the cabin CO levels get too high in order to save the occupant's life? Now, THAT would be something, wouldn't it?
17: nitrogen oxide value
I wonder what it does with these values? Are they cabin readings or outside air readings?
I wonder if the car will shut itself off if the cabin CO levels get too high in order to save the occupant's life? Now, THAT would be something, wouldn't it?
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From: SF Bay Area
2002 C230 K
Originally posted by tberry
Used to have those on my audi a4
but oh well. does these only show on c320/C32 or anyone with digital climatronic?
Used to have those on my audi a4
but oh well. does these only show on c320/C32 or anyone with digital climatronic?
Originally posted by r_1_c32
I tried it today, but I only get a blinking of "00" on the left side, and "21" on the right side. How do you actually do the reading? Thx
I tried it today, but I only get a blinking of "00" on the left side, and "21" on the right side. How do you actually do the reading? Thx
- BT
Last edited by trench; Feb 5, 2003 at 05:42 PM.
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Originally posted by r_1_c32
I tried it today, but I only get a blinking of "00" on the left side, and "21" on the right side. How do you actually do the reading? Thx
I tried it today, but I only get a blinking of "00" on the left side, and "21" on the right side. How do you actually do the reading? Thx
After experimenting I found that when I pushed in on the drivers side rotary knob it would change states. I tried to get the info for all the codes from my dealer. He showed me the book and guess what. Your right - go to DAS.
I loved the look on his face when I asked for this info. Kinda like - WTF.
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From: Toronto, ON, Canada
MY2001 C320
There was a thread about a year ago on same topic.
Actually, you don't need to hold the 0 button. Just hold EC button for 5 seconds and the display will show 00 code. Press the left Auto button to move up the chain (00, 01, 02), and right button to move down. The code and value will alternate on the left and right end of the display. When showing RPM, it is in 10s. So a value of 153 means 1530 rpm.
One point of note is the speedo on the dash (analog and digital) is intentionally set higher than the actual value by approx. 3%. This is done to give the driver a margin of error when approaching posted speed limits. However, the car must know the "true" speed for various sensor inputs, like ESP. The digital AC display shows the true speed. You can try this by comparing the digital display true speed with the digital speedo in the dash. The difference is about 3%. So 60mph true speed is shown as 62mph in the dash.
Yes, the earlier thread I mentioned listed many more codes, but I can't remember what they are now.
Actually, you don't need to hold the 0 button. Just hold EC button for 5 seconds and the display will show 00 code. Press the left Auto button to move up the chain (00, 01, 02), and right button to move down. The code and value will alternate on the left and right end of the display. When showing RPM, it is in 10s. So a value of 153 means 1530 rpm.
One point of note is the speedo on the dash (analog and digital) is intentionally set higher than the actual value by approx. 3%. This is done to give the driver a margin of error when approaching posted speed limits. However, the car must know the "true" speed for various sensor inputs, like ESP. The digital AC display shows the true speed. You can try this by comparing the digital display true speed with the digital speedo in the dash. The difference is about 3%. So 60mph true speed is shown as 62mph in the dash.
Yes, the earlier thread I mentioned listed many more codes, but I can't remember what they are now.
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for 2002
On 2002 C32 (digital A/C)
While the vehicle is on and the A/C is in operation, hold down the “REST” button for several seconds until the system goes into the A/C diagnostic mode.
On C32,
Pressing AUTO LEFT Side for 'up' and AUTO RIGHT Side for 'down'
On other C-class A/C,
Pressing “Air up' and 'Air down'
you can shift thru various a/c diagnostic registers.
Cycling through will show you the diagnostic register and its corresponding value.
Go to register 01 and make sure it reads what it should for inside air. BTW Mine is in F not C.
Then you are off to the races.
While the vehicle is on and the A/C is in operation, hold down the “REST” button for several seconds until the system goes into the A/C diagnostic mode.
On C32,
Pressing AUTO LEFT Side for 'up' and AUTO RIGHT Side for 'down'
On other C-class A/C,
Pressing “Air up' and 'Air down'
you can shift thru various a/c diagnostic registers.
Cycling through will show you the diagnostic register and its corresponding value.
Go to register 01 and make sure it reads what it should for inside air. BTW Mine is in F not C.
Then you are off to the races.
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Just got to play with this secret sauce this morning. Gotta love secret sauce...
I noticed that some displays for temp read celsius, others read fahrenheit... but my speed reads in KPH. Need to play more.
QQQ, did your dealer provide you all the codes? Can you get them, please? Or is the list posted on one of the other forums? I don't recall this thread on this forum, but of course it could be present on others.
My display runs all the way up to measurement 61, then 62-?? read 00 to the right. I did notice that upon first entering this mode, if you "page down" (press right AUTO button) it starts with measurement value 99 and down, and some of these have values associated with them.
I noticed that some displays for temp read celsius, others read fahrenheit... but my speed reads in KPH. Need to play more.
QQQ, did your dealer provide you all the codes? Can you get them, please? Or is the list posted on one of the other forums? I don't recall this thread on this forum, but of course it could be present on others.
My display runs all the way up to measurement 61, then 62-?? read 00 to the right. I did notice that upon first entering this mode, if you "page down" (press right AUTO button) it starts with measurement value 99 and down, and some of these have values associated with them.
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From: Bloomington, IN
1997 Toyota Tacoma 4x4
I have the complete list, although most of them aren't meaningful to non-technicians. Such things as auxiliary fan duty cycle readings, heater box flap percentage readings, hardware and software status, A/C compressor torque.
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Re: W203 air conditioning diagnostic mode (C320/C32 only)
Originally posted by mbtech208
Push "EC/REST" button until display changes (approx. 5 seconds)
I've only included the values that may be of interest to owners
22: vehicle speed
24: battery voltage (very handy)
Push "EC/REST" button until display changes (approx. 5 seconds)
I've only included the values that may be of interest to owners
22: vehicle speed
24: battery voltage (very handy)
Now, 24 produce a readout of 42. I know that 42 Volt systems are not yet in production cars. What gives?
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From: Toronto, ON, Canada
MY2001 C320
MB-BOB: No, I didn't get this from dealer, but from this forum. Alas, it was a very antique thread dating back to 2001 and since purged.
amdeutsch: My car is Canadian and uses celsius / km/h. What you can do is go to the setting and change the digital display from mph to km/h, and F to C.
Those driving old E-Class, you should press Rest button, not EC.
amdeutsch: My car is Canadian and uses celsius / km/h. What you can do is go to the setting and change the digital display from mph to km/h, and F to C.
Those driving old E-Class, you should press Rest button, not EC.
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From: Bloomington, IN
1997 Toyota Tacoma 4x4
Originally posted by MB-BOB
Well, Dave, can you share, anyway? Don't just tease us with half the story! Pretty please?
Well, Dave, can you share, anyway? Don't just tease us with half the story! Pretty please?
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Originally posted by QQQ
amdeutsch: My car is Canadian and uses celsius / km/h. What you can do is go to the setting and change the digital display from mph to km/h, and F to C.
amdeutsch: My car is Canadian and uses celsius / km/h. What you can do is go to the setting and change the digital display from mph to km/h, and F to C.
Or were you refering to the fact that I should change my FSS readout to match the climatronics readout. ?????
In either case I don't believe that the voltage readout, setting 24, is going to be different between countries.
Overall what I was stating with my post was that there were inconsistencies with what you get versus what you might expect.
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From: Ohio
2010 C300 4matic
Hey, I tested this today on a new S-class. Worked like a charm, just held rest. I didn't have the list of what they meant though, so I just scrolled through a couple. The first 10 or 15 were all temperatures and they were in celsius.
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From: BC, Canada
2003 C230K Coupe Orion Blue
Time to revive an old thread.
My 00 (panel temperature) and 02 (outside temperature) look correct, but the 01 (dome light temperature sensor) is jumping all over the place. Between flashes it'll bounce like 0, 42, 17, 19, 37. Anyone ever see this before?
Not sure if it makes a difference, but I retrofitted the Climatronic dual zone panel into the car. The car originally came with the analog panel.
If the thermistor is indeed bad, anyone ever replace this component? If so, any tips or advice?
My 00 (panel temperature) and 02 (outside temperature) look correct, but the 01 (dome light temperature sensor) is jumping all over the place. Between flashes it'll bounce like 0, 42, 17, 19, 37. Anyone ever see this before?
Not sure if it makes a difference, but I retrofitted the Climatronic dual zone panel into the car. The car originally came with the analog panel.
If the thermistor is indeed bad, anyone ever replace this component? If so, any tips or advice?
Last edited by slammer111; Oct 8, 2024 at 12:21 AM.
