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OK. So I ran the diagnostic for the climate control today and I got A LOT of codes. However, I did replace the unit with a used unit maybe 18 months ago because the display in mine failed so maybe the codes were on the unit already. Anyway, after reading all the codes, I cleared them, drove around for a bit and they DID NOT come back on. So anyway if anyone is knowledgeable on these -- let me know. Problem is that the A/C isn't blowing cold.
Here's what it spit out at me:
(I think these were all intermittent because they all had the little degree symbol)
22°6
22°8
23°0
23°2
23°3
41°6
41°7
41°9
42°1
42°2
45°9
45°1
45°2
45°3
45°4
45°5
45°6
So uh yeah that is a lot of codes, maybe because the unit is out of another car, no idea.
Anyway, so I ran a system check and then I got this:
01 90°F
02 103
03 143 (dropping fast cause I had the heat on before I ran the test)
05 103
06 199
07 03°7
08 134
09 50°F
10 175
20 00
21 060
22 000
23 100
40 01
41 03
42 02
43 6-C
50 113
51 72°F
52 44°F
54 OFF
Must have happened over the winter. It still blows, just not cold and it doesn't look like a leak because system says:
07 03°7
so looks like good pressure no leak. Guessing its the compressor or something. Maybe i will throw in the old unit to see if that does it. cant remember if it was working after new unit.
SENSOR VALUE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
------------------------------------------------------------
Code Cause/Value
01 ............................. In-Car Temperature Sensor
02 ............................ Outside Temperature Sensor
03 ........................ Heater Core Temperature Sensor
05 .................... Evaporator Core Temperature Sensor
06 ................. (1) Engine Coolant Temperature Sensor
07 .............................. (2) Refrigerant Pressure
08 ............................ (3) Blower Control Voltage
09 .......... Software Status Of A/C-Heater Control Module
15 ........................... Selected In-Car Temperature
20 ................................. Software Version Code
21 ...................................... (4) Engine Speed
22 .............................. (5) A/C Compressor Speed
23 ......................................... Vehicle Speed
50 ................................ 80.° - 00.° (Not Used)
51 ......... Number Of Actual Drive Belt Slip Recognitions
52 ......... Number Of Actual Drive Belt Slip Recognitions
(1) - A display of "12.°5" corresponds to 125 Celsius (257°F).
(2) - Refrigerant pressure is displayed in bar. One bar equals 14.5037 psi. A display of "12.°8" corresponds to 12.8 bar (185.6 psi).
(3) - A display of "16.°5" corresponds to 1.65 volts.
(4) - A display of "06.°0" to "70.°0" corresponds to 600 RPM to 7000 RPM respectively.
(5) - A display of "00.°0" to "84.°0" corresponds to 0 RPM to 8400 RPM respectively.
Heres the others: (hoping one of these codes pops up after the reset so i can figure it out)
FAULT CODES
DTC Readout Descriptions
026 CAN Bus Communication
226 In-Car Air Temperature Sensor (B10/4)
227 Outside Air Temperature Sensor (B14)
228 Heater Core Temperature Sensor (B10/1)
230 Evaporator Temperature Sensor (B10/6)
231 Engine Coolant Temperature Sensor (B11/4)
232 Refrigerant Pressure Sensor (B12)
233 Refrigerant Temperature Sensor (B12/1)
241 Refrigerant Level
416 Coolant Circulation Pump (A31m1)
417 Left Duovalve (Water Valve) (Y21y1)
418 Right Duovalve (Water Valve) (Y21y2)
419 A/C Compressor Electromagnetic Clutch (A9k1)
420 Closed (Idle) Throttle Speed Increase
421 Pulse Module (N65)
422 Serial Interface Connection (K1) to Instrument Cluster (IC)
451 Diverter Flap (Y11/3)
452 Blend Air Flap (Y11/3)
453 Fresh/Recirculated Air Flap (Y11/3) Long Stroke
454 Fresh/Recirculated Air Flap (Y11/3) Short Stroke
455 Defroster Outlet Flap (Y11/3) Long Stroke
456 Defroster Outlet Flap (Y11/3) Short Stroke
457 Footwell Flap (Y11/3) Long Stroke
458 Footwell Flap (Y11/3) Short Stroke
459 Serial Interface Connection (K2) to Instrument Cluster (IC)
462 Wide Open Throttle (WOT) Position Signal - Diesel Engine Only
Quit worrying about the codes at this point. Look at the live data. You have 3.7 bar on the compressor discharge - live data point 07. Either the compressor is failed or the system needs to be charged. Have it charged with refrigerant and dye. My guess is the system will then cool. It likely has a slow leak and eventually that will have to be repaired.
Vince, all my reading says to start right there. I'm going to have the system evacuated and then refilled. I think it requires 2.1 lbs of refrigerant. So I'll put the stuff with the dye in there and see how it goes.
What I read the compressor won't engage if the refrigerant is low and the pressure is not an indicator of refrigerant as it is added by weight.
It is easy to see if the clutch is engaged. And yes, the system should be charge by weight - in the case of the C43 it is 1.9 lbs - 0.7 lbs. However, as the charge goes down the discharge pressure drops. Normal discharge pressure is around 8 bar +/- rolling and as high as 16 bar stopped with the engine idling on a warm day.
I just replaced the compressor on my son's C43 today. It wasn't cooling. The compressor was engaged and showing 4.6 bar. I evacuated it, charged it with dye and within 30 minutes the dye began to show up leaking from the compressor seal. Many people over science these systems. I have the advantage of having proper tools including a charging manifold, so I can look at both suction and discharge pressures. But the live data in the control unit gives you all you need in 90% of the cases.
So I gave it a lot of thought on what the right thing to do was. I know it sounds stupid like why would I have to think about it, but that's just the way I am. I decided to just hit it with the cheapest solution possible since its already broken. I had a full 12oz can of refrigerant laying around so I decided to charge it up and see what happened.
I probably put in about 8 to 10 oz of this stuff. Maybe should have weighed the can before I used it. Hindsight is a MF. Anyway, compressor kicked on and A/C started blowing ice cold. Next time I'll buy a can with some dye in it and see where she is leaking from, but I'll probably be good for this summer and I think that can was less than $15 at Walmart with the connector.
I am sorry Plutoe, but you are wrong about the pressures. The pressure at idle is always higher because of the relatively lower air flow across the condenser compared to driving down the road (at any speed over 20mph or so). His pressures look OK to me, for now at least. You are correct that he will have to fix it down the road, but I think he knows that.
do you have any wis information sheet or something that shows your explanation? i have the wis discs but never installed them. maybe i will give it a shot in a couple of days.
also i think the compressor will not engage if pressure is too high. i cant say for sure in this car but this is the case in many other cars.
also i am here to ask questions for a number of reasons, 1. i like doing repairs and working on cars, 2. i dont have a good indy, 3. i dont trust the stealership, have brought my car there many many many times and they lie about everything and never fix anything, i found myself having to tell the dealer exactly what was wrong with the car and how to fix it.
if you think i am whining, pls keep your information to yourself, i am sure there are more than enough ppl here who like to discuss cars without snide remarks and my questions can be answered without your help.
not to get off topic on this thread cause it seems good, but the only thing i can do on my Climate Control is putting the key in ON position, have the AUTO in low And push the EC/ and the REST button, and hit AUTO to browse through any codes. and clear with the up hot/ down cold buttons. Is that how you read the values on how to know if anything is bad?
On the later CC modules you read the live data by pressing and holding the REST button for 5 seconds or so. The readout will shift from the normal screen to live data, beginning with 01. The location, i.e. the point from which the data is being read, alternates with the actual data. The live data provides temperatures and pressures that are helpful in seeing what the system is doing. If I see something out of range I always follow this check by hooking up my charging manifold and looking at the low side pressure. To go back to the normal screen press the REST button briefly.
thanks vince. i guess i missed the live data on the cc unit. i always knew there was something else.
on the diags i ggot the foowing.
41.6
41.7
41.9
42.1
45.9.
After i clear them, i still get 45.9.
You can't clear live data. Think of it as a pressure gauge or a thermometer. I guess I should have mentioned how you change the data point. Press the fan + for to scroll forward through the menu and fan - to go back. Here are the ones I check:
01 - Inside temp
02 - Outside temp
03 - Heater core temp (this will can be considered as conditioned air going to the cabin)
05 - Evaporator temp
06 - Engine coolant temp
07 - High side pressure (compressor discharge)
right, there are two diagnostic modes. the one you are looking at is the codes, the other is the live data. like vince said, just turn on your car put the a/c on low and then hold the "rest" button until it starts with the data. then use the fan + and - keys to toggle through the data.
You can't properly test or diagnose the system by looking at only that data. You need an AC machine that can evacuate system and then charge full. Or at minimum a set of gauges. Anything else you're throwing a dart at the board.
Sounds like your system was low. I'm sure it's a leaking condenser like 99% of 202's with low refrigerant.
Getting T-Rex ready for the technical roadworthy test (every two years) tomorrow. Everything is good to go. I changed back to my 17" Monos which has tyres with plenty of profil. 18" will be an automatic rejection of the vehicle as this size was never a MB OE approved size for the w202. I've just left my secondary cats and resonator delete and hope they don't see it...
After that I decided to pull the error codes from the climate control which I had never done before. These came up on the screen:
41.6
41.7
41.9
42.1
45.1
45.3
45.4
45.5
45.6
I deleted all the codes and I'll chack again after driving around some time. Otherwise, the HEVAC works perfectly and has plenty of cold air since a recent recharge, so I guess the codes must be old errors which have never been deleted.
Here in New Jersey the inspection is every two years as well, but they only check emissions, nothing else.
They connect car to the computer and if the car is not throwing any codes you pass automatically. If the car is throwing a code then they connect pressure hose to your gas cap and I think they measure emissions from tailpipe. You can pass if car is throwing code but check engine light is not on.
If check engine light is on then you fail automatically.
The test is definitely more complicated. Any faulty safety related parts, such as steering, brakes, suspension gives an automatic reject. Rust holes on the chassis is a reject. Non standard lights or non adjusted headlights are rejects. Emisions over official Factory determined levels are rejects. Any leaks by any liquid is a reject.
You can consider your tests very simple indeed.
Edited to say that she passed the inspection this morning even with the secondary cats and resonator delete. The inspector did check the rear muffler ID# to see if it was the same as what is normally fitted on the c43. Didn't look or wanted to see the other part. Only negative point is the fog lights which need to be permanently disconnected. With the KW lowered suspension, the lights are under the mandatory minimum 25cm from the ground. I don't mind because I never use the fog lights in any case.
Last edited by DRBC43AMG; 06-09-2016 at 04:10 AM.
Reason: Completed post
05-14-2016, 07:40 PM
Climate Control Q.
