What else is MB hiding?
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From: Orlando
E550 Coupe
What else is MB hiding?
For the past couple of months I've been asking around to see if anyone here/the tech could help me with my 'EC' light staying on and the AC compressor not running because of that. The problem was pretty much isolated down to the hvac control module but no one could tell me how to reset this to clear the error codes. I was quoted $500 for a new head unit. But today I accidentally fixed it when I was trying to bring up the error codes. I made a mistake and somehow went into a mode where the left said "1," the right said "232," and I was able to change the right value higher/lower by pressing up/down. I wondered wtf was happening and turned off the ignition...turned it back on and bam, 'EC' stayed off.
Is MB hiding this special mode from its dealers/techs so that they can make more money when something like this happens? Or is this occuring one level below? Who knows what other electrical stuff we don't know about
Is MB hiding this special mode from its dealers/techs so that they can make more money when something like this happens? Or is this occuring one level below? Who knows what other electrical stuff we don't know about
MBWorld Fanatic!
Joined: Apr 2003
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From: SoCal OC
S, GL, Escalade ESV, my shoes
Re: What else is MB hiding?
It's the diagnostic via the Climate Control monitor.
You can do it as follow:
* Set temperature of both side to same (i.e 68).
* Keep pressing the REST button til you see the screen change (it will)
* Press up and down to see it give reading of different sensors & current in your car
There's a list of sensor reading out there, do a search and see what I mean.
I used this method to isolate problem w/ my aux fan and fixed it.
You can do it as follow:
* Set temperature of both side to same (i.e 68).
* Keep pressing the REST button til you see the screen change (it will)
* Press up and down to see it give reading of different sensors & current in your car
There's a list of sensor reading out there, do a search and see what I mean.
I used this method to isolate problem w/ my aux fan and fixed it.
Originally posted by iosmart
For the past couple of months I've been asking around to see if anyone here/the tech could help me with my 'EC' light staying on and the AC compressor not running because of that. The problem was pretty much isolated down to the hvac control module but no one could tell me how to reset this to clear the error codes. I was quoted $500 for a new head unit. But today I accidentally fixed it when I was trying to bring up the error codes. I made a mistake and somehow went into a mode where the left said "1," the right said "232," and I was able to change the right value higher/lower by pressing up/down. I wondered wtf was happening and turned off the ignition...turned it back on and bam, 'EC' stayed off.
Is MB hiding this special mode from its dealers/techs so that they can make more money when something like this happens? Or is this occuring one level below? Who knows what other electrical stuff we don't know about
For the past couple of months I've been asking around to see if anyone here/the tech could help me with my 'EC' light staying on and the AC compressor not running because of that. The problem was pretty much isolated down to the hvac control module but no one could tell me how to reset this to clear the error codes. I was quoted $500 for a new head unit. But today I accidentally fixed it when I was trying to bring up the error codes. I made a mistake and somehow went into a mode where the left said "1," the right said "232," and I was able to change the right value higher/lower by pressing up/down. I wondered wtf was happening and turned off the ignition...turned it back on and bam, 'EC' stayed off.
Is MB hiding this special mode from its dealers/techs so that they can make more money when something like this happens? Or is this occuring one level below? Who knows what other electrical stuff we don't know about
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From: Milton/Westport, MA USA
me: 2015 SL400 & 2015 ML400; wife: 2022 GLC Coupe; daughter: 2017 GLC SUV
zam, what else can be diagnosed w/ this method? I have CEL on and it's not because of gas cap or MAF. would I be able to learn anything this way?
Thread Starter
MBWorld Fanatic!
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From: Orlando
E550 Coupe
Nah, it's not that diagnostic. This was somethig totally different. You could actually CHANGE the values on the right to whatever you wanted to. In regular diagnostic it would just display the reading. It was also NOT the error code diagnostic because there was just a "1" on the left.
Last edited by iosmart; Jun 8, 2004 at 07:31 PM.
Thread Starter
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From: Orlando
E550 Coupe
eddio, what you might want to try is bringing up the error codes. Go to http://www.continentalimports.com/ser_ic40142.html and scroll down a bit.
Super Member
Joined: May 2004
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From: USA
LS7 powered Corvette
MB does not hide anything. The only thing I have discovered is on some command units where you can pull up fault codes/diagnostics but they are installed into the unit by the manufacturer of the electronics, no MB themselves. On those, the codes etc. dont do anything for the tech.
The A/C pushbutton diag. and sensor values is well known by MB techs. I use it on 210 and 208 chassis to test alternator output. Value 24 is battery voltage so once I get the car started, I just turn on the accesories(headlights, window defroster) to load the battery and if the battery voltage is too low or dropping, I know the alternator is not chariging. Piece of cake.
The A/C pushbutton diag. and sensor values is well known by MB techs. I use it on 210 and 208 chassis to test alternator output. Value 24 is battery voltage so once I get the car started, I just turn on the accesories(headlights, window defroster) to load the battery and if the battery voltage is too low or dropping, I know the alternator is not chariging. Piece of cake.
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Joined: May 2004
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From: Albuquerque, NM
09' E350, 01' Maxima SE, 93 Nissan Maxima SE, 1987 Nissan Maxima SE
That's a good post, I did not know the A/C has it own diagnostic error code on it. Now I can look out just in case if I ever get some kind of error code on it.
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From: Orlando
E550 Coupe
CRS, I repeat myself - it was neither the error code diag nor the diag that contains:
1 in-car temp
2 temp outside
3 heater core temp, left
4 heater core temp, right
5 evaporator core temp
6 engine coolant temp
7 refrigerant pressure (in bars)
8 refrigerant temp
9 not used
10 blower control voltage in range .8 - 6V (max)
11 air pollution sensor
12 sun sensor
20 control current of aux fan
21 engine RPM (x 100)
22 vehicle speed, km/h
23 terminal 58d battery charge, percent
24 battery voltage
40 software status register
41 hardware status register
For the error code diag it would say Eb1 to the left; what I found just said "1". And that doesnt automatically mean that I was in the other diag because it does not let you change the temperature reading on the right hand side. Try it and see. This was something else. Nothing was physically wrong with my system. Everything was in perfect working order. The control module had some sort of software malfunction. The key is that whatever I did allowed me to reset the problem that was keeping my module from functioning normally. I looked and looked but couldn't find anything like this reported on the board and the dealer said they couldn't help me either. Not even the tech that moderates this section could help me.
1 in-car temp
2 temp outside
3 heater core temp, left
4 heater core temp, right
5 evaporator core temp
6 engine coolant temp
7 refrigerant pressure (in bars)
8 refrigerant temp
9 not used
10 blower control voltage in range .8 - 6V (max)
11 air pollution sensor
12 sun sensor
20 control current of aux fan
21 engine RPM (x 100)
22 vehicle speed, km/h
23 terminal 58d battery charge, percent
24 battery voltage
40 software status register
41 hardware status register
For the error code diag it would say Eb1 to the left; what I found just said "1". And that doesnt automatically mean that I was in the other diag because it does not let you change the temperature reading on the right hand side. Try it and see. This was something else. Nothing was physically wrong with my system. Everything was in perfect working order. The control module had some sort of software malfunction. The key is that whatever I did allowed me to reset the problem that was keeping my module from functioning normally. I looked and looked but couldn't find anything like this reported on the board and the dealer said they couldn't help me either. Not even the tech that moderates this section could help me.
Last edited by iosmart; Jun 13, 2004 at 05:41 PM.
Member
Joined: Mar 2004
Posts: 132
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From: Dallas, TX
2007 Mercedes SL550 Sport
so to try and reset the EC, I'll bring up the diagnostic on the cliamte control panel by holding the 'REST' button, and the left and right temp setting set to the same temp.
now I just change the values on teh right side then turn off the car and back on to see if the EC light is on? is there a exit mode? just double checking. thanks
now I just change the values on teh right side then turn off the car and back on to see if the EC light is on? is there a exit mode? just double checking. thanks
Thread Starter
MBWorld Fanatic!
Joined: Jun 2003
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From: Orlando
E550 Coupe
Long long time ago and even when I got it to reset, I wasn't totally sure what I did. Are you sure your AC is technically in working condition? The EC may come on if it leaks all its gas or something else is broken.
