Garage Cabinets, Garage Storage, and Garage Organization

to be certain if the evap sensor is really the problem try to get ohmeter, measure the sensor's resistance from the corresponding temperatures:

degree celsius            K ohms
10 deg cel        =        5.2-5.8 K ohms
20 deg cel        =        3.2-3.6 K ohms
30 deg cel        =        2.0-2.3 K ohms
45 deg cel        =        1.1-1.25 K ohms


_________________
W I N D Z
Once is enough, twice is too much, thrice is a disaster...

you can check the actual value through the control unit. for example the actual value for evaporator temperature is 6'C but the value display on the screen of the ac control unit is 60'C, then the sensor needs to be replaced.


goodluck and please give updates


_________________
W I N D Z
Once is enough, twice is too much, thrice is a disaster...

When You say on the dispaly, we are still talking about the test mode that shows the values right?, in other words parameter 05?....

Also, I'm posting Farenheit values for your table...

50    deg F        =        5.2-5.8 K ohms
68    deg F        =        3.2-3.6 K ohms
86    deg F        =        2.0-2.3 K ohms
113  deg F        =        1.1-1.25 K ohms

Please advise...

mechefan wrote:

When You say on the dispaly, we are still talking about the test mode that shows the values right?, in other words parameter 05?....

Also, I'm posting Farenheit values for your table...

50    deg F        =        5.2-5.8 K ohms
68    deg F        =        3.2-3.6 K ohms
86    deg F        =        2.0-2.3 K ohms
113  deg F        =        1.1-1.25 K ohms

Please advise...

yes.

 i've asked 2nd opinions on my colleagues before regarding your problem and they all agreed that it could be the evap sensor.


_________________
W I N D Z
Once is enough, twice is too much, thrice is a disaster...

ok, I have to sadly announce that I replaced the evaporator sensor, and my system did not work....I however noticed that the compressor would now turn on and off pretty often, which translates to me into yes, the sensor had some issues........but the worst part of all is that I went and check the error codes and the same 232 kept showing but worse than that error 416 showed   , and from the code list means that my compressor is bad?   I'm lost again, how come it never showed me that error before?, I remember seeing good pressures when I had the gauges hooked up.....


Is my diagnostic right?...

  weirder than weird!!!!  

After of 2 days of no a/c, and as You can read on my previous post, erasing the codes, something very weird happened....the a/c starting working!!!!....I left the a/c running because I was hoping for a miracle, and yesterday, as I was taking off from my house I noticed cold air coming out of the vents!, so I said Good!, that means that the system probably needed to read all the inputs from the a/c a couple of times to start working properly.

This drive I took was 40 minutes long, the air was so cold that I was really amazed how well it worked!, so amazed that decided not to change the temp settings  (LO) until I reached my destination....what happens after those 40 minutes?...I stop, turn the engine off, run some errands and when I started my car again and checked the air,  it felt cold, but only for a few minutes!!..  I said to my self, wait a minute, it sounds like the failure of the evaporator sensor!!, but I had just changed it!!

Anyway....I drove back  40 minutes drive with no a/c   ...

So this morning....as soon as I entered  the car I checked on the codes, it gave me 232, 416, 419.   The refrigerant pressure sensor, ( this error keeps coming back ), coolant circulation pump ( 2nd time it shows it ) and electromagnetic clutch.

I Decided to erase them again, after turning my engine on and off to see if in fact the codes had been erased, the a/c worked just fine again, and it worked for the 20 minutes it takes me to get to work!. and I checked the codes, ...NONE!

I do not want to change the compressor yet, because I honestly believe that if the compressor was failing, there was no way it could run 40 minutes extremely well, and all of the sudden stop. I could believe that if the clutch was not working properly, it could cause the brain (n22) to think it is the compressor that is bad, but I keep trying to figure out, why and why that 232 error keeps coming back! (Could it be that the compressor by not compressing the gas, does not allow the sensor to read adequate temperatures, thus creating an error ).

I'm open to ideas to troubleshoot this before I change my compressor, in the mean time I'm going to take the readings again while the system works.....

Thanks for reading

i don't think it's the compressor too, you should look out for your N22.


_________________
W I N D Z
Once is enough, twice is too much, thrice is a disaster...

Last night my a/c worked fine from work to home, checked the codes and everything was ok, however this morning the a/c did not work, and I immediately after noticing it I checked the codes, it showed 419, I erased it and went to work, It did not work all the way there, then I checked the codes and there were none.

is n22 from a 1997 c230 model would work on my c280 1998? my brother has one, and I want to borrow it....what Do You think?...

I'm looking at somecodes I took this morning..

01- 79
02- 110
03- 81
05- 83
06- 197
07- 89
08- 98
09- 32
10- 335

if 02 is the outside temperature, I know something is wrong, this morning the outside temperature was 82F not 110, does that have anything to do with the a/c not working?...

I have asked my brother to send me the n22 unit he has, it wil arrive tomorrow night, I'll keep You guys up to date....

mechefan wrote:

is n22 from a 1997 c230 model would work on my c280 1998? my brother has one, and I want to borrow it....what Do You think?...

this is great coz i think your brother's AC is also code 581a.


_________________
W I N D Z
Once is enough, twice is too much, thrice is a disaster...

the outside temperature sensor doesn't have much effect on the actuation of the compressor. the information is relayed via the instrument cluster and serial interface k1 to the push button control module. this information causes a slight reduction or increase of the temperature set on the push button control module. this provides greater comfort by adapting the temperature to the temperature perceived subjectively by the passengers.

the interrelationship between the outdoor temperature and vehicle speed prevents an excessively high temperature from being relayed to the AC control unit, when the vehicle is standing still or driving slowly resulting from heat being radiated from the engine.

the temperature measured last is used when the ignition is switched off and on and at speeds below 20km/h.


_________________
W I N D Z
Once is enough, twice is too much, thrice is a disaster...

I forgot to tell You that when I see a difference between the reading of the temperature at the N22 and the "real outside temperature" is that I'm relaying on the instrument cluster,  I though both temperatures should match, or is there another temperature sensor I do not know about?...

what great affects the actuation of the compressor is the ECT sensor (coolant temperature sensor). the ECT sensor sends resistance value corresponding to the coolant temperature via the instrument cluster and the serial interface k1 to the push button control module. here the value is processed and the AC compressor is switched off in two stages...

stage 1- at a coolant temperature greater than 123 deg cel the duty factor is reduced is reduced by 50%. in this case the compressor is switched on in cycles, ie; off approximately 20 sec and on approximately 20 sec. if the coolant temperature drops to below 123 deg cel the AC compressor is switched on again permanently.

stage 2- at a coolant temperature greater than 127 deg cel the AC compressor is switched off completely. when the coolant temperature drops to below 127 deg cel the AC compressor is switched back on in the cycle mode (stage 1).

regarding the outside temperature sensor, there should be just a little difference reading from the instrument cluster and the reading from AC push button control module.


_________________
W I N D Z
Once is enough, twice is too much, thrice is a disaster...

ok, so if my display shows x F temperature and the n22 shows +15 F,  that means one of the 2 is wrong, I know the one from the cluster is fine, because it matches what they say on the radio. So, where do I find the one that shows on the n22?...

by the way, the n22 from my brother's car is going to take another extra day...