[DCook]

I for the love of me cannot figure this out. I've replaced the compressor, expansion valve is new, and I've traced wires from the rear passengers controls, as per other threads, and its all fine, no cracks or cuts, etc..

The weird part is, if you mess with it enough clearing the codes and messing with the controls once in a blue moon it'll work beautifully, and work until the next vehicle restart, and wont until the next day it usually seems. Now, i cant get it to work at all. It throws the code in the picture, but i cant seem to quite figure it out. If i could code out the rear heat/ac controls i would. But i dont know the coding for it.

Hoping someone around here knows and has been through this! Is there a control valve for the rear under the hood? Or is there a value in inpa that corresponds to the rear control, like there is the front selector? I've watched the front, but cant seem to find the rear in inpa.

[Fritzer]

Mine stopped working recently as well, took it has a sign to delete the compressor and get a smaller belt. Natural aspiration things.

[DCook]

Originally Posted by Fritzer

Mine stopped working recently as well, took it has a sign to delete the compressor and get a smaller belt. Natural aspiration things.

I really would hate to do that. I sold my 408 stroker foxbody, so i could build this thing, nothing like having a giant single turbo, while keeping a/c, and heated seats. I had my fun without luxury amenities, not wanting to do it again haha.

[Nikkitta]

Originally Posted by Fritzer

Mine stopped working recently as well, took it has a sign to delete the compressor and get a smaller belt. Natural aspiration things.

+1

[marvinstockman]

Stupid question, but does it have enough R134A. What is the static pressure, with engine cold and not running. Include ambient pressure.

[DCook]

Originally Posted by marvinstockman

Stupid question, but does it have enough R134A. What is the static pressure, with engine cold and not running. Include ambient pressure.

I believe it was around 125-135psi. But yeah, it has enough refrigerant. It worked beautifully before the code issue. If it was low on refrigerant i wouldnt believe it to cause the code as I've charged it 2 times now, for each part change. And i can get it working if i mess with it enough clearing the code and messing with controls. Just wish there was a solid answer directly torwards why its being a pain.

[rick100]

Originally Posted by DCook

I believe it was around 125-135psi. But yeah, it has enough refrigerant. It worked beautifully before the code issue. If it was low on refrigerant i wouldnt believe it to cause the code as I've charged it 2 times now, for each part change. And i can get it working if i mess with it enough clearing the code and messing with controls. Just wish there was a solid answer directly torwards why its being a pain.

stupid question but does it work if you unplug the battery and plug it back in after sometime. You keep saying it works sometimes after resetting the settings , etc ,etc ,etc. Since you have already replaced some major components, I would try to see if your theory on the settings is correct and is more of a "computer" issue rather than a mechanical issue ...

I had the weirds issue with my suv where my fob wouldnt work , the tire monitor pressure light was on at all times , i was not able to see my tire pressure. I took the car to the dealer , they said it was a wiring issue or maybe the computer . They quoted me like 800$ or more depending on what they found , I told them , screw it , i dont need the remote to open the door and i know my tire pressure is good.
I replaced my battery last year , as soon as i restarted the car with my new battery , everything started to work .

I think it may be worth a try , at least it may help you realized if your issue is related to the computer or battery , rather than a mechanical component that is failing

[marvinstockman]

DC, if your static pressure, engine off and engine cold, is 125 psi, and depending on outside temperature, you're probably overcharged.

Google R134A, pressure vs. temp chart.

[dpaul]

True, you probably overcharged unless it was 100F+ on the day you measured.

However, that's not likely the real problem

The error 9c69 (Rear cabin stratification adjuster) does not relate to your compressor. IKHA adjusts the flow of hot and cold air with a set of electronically controlled stepper motors connected to flaps. Input to this system is electrical through a potentiometer which is adjusted by those wheels in the vents with red and blue marks. The code suggests a frayed, pinched or disconnected wire to the potentiometer in the rear center console

I'd remove the central part of the armest/console and look for problems with the wires.

[e90yyc]

When you say you charged it, did you do this yourself or take it to a shop? The AC system in these cars can be one finicky son of a whore.

What is pressure on low side with system running (assuming it’s one of those blue-moon days when it works...)?

What initially led to you changing the compressor? Did this mysterious issue you’re having precede the compressor change?

[gbalthrop]

Originally Posted by DCook

...The weird part is, if you mess with it enough clearing the codes and messing with the controls once in a blue moon it'll work beautifully, and work until the next vehicle restart, and wont until the next day it usually seems. Now, i cant get it to work at all...Or is there a value in inpa that corresponds to the rear control, like there is the front selector? I've watched the front, but cant seem to find the rear in inpa.

Originally Posted by DCook

I believe it was around 125-135psi. But yeah, it has enough refrigerant. It worked beautifully before the code issue. If it was low on refrigerant i wouldnt believe it to cause the code as I've charged it 2 times now, for each part change. And i can get it working if i mess with it enough clearing the code and messing with controls. Just wish there was a solid answer directly torwards why its being a pain.

Please Define "Stopped Working." That covers a LOT of territory:
1) Does the Climate Control Panel light up?
2) Blower work at Manually-controlled speeds?
3) Heat work?
4) Everything but cold air output?
5) BOTH Left & Right sides same air temp with L & R Thermostats BOTH set to 60F (Lowest setting)?
6) Does air delivery change when you press the buttons (Footwell, Ventilation/facia, Windscreen) on the left side of the control panel?
7) WHAT does NOT WORK?
8) WHAT led you to replace the Compressor & Expansion Valve?
9) Do you have INPA, and know how to connect to IHKA Module?

BTW, one of us, including Carly can't count. It says 8 Faults, but you only show 3, 2 TPMS Transmitter Faults and the Rear Stratification Flap Motor Fault. NONE of them would relate to A/C NOT working. The Flap Fault is shown as being in the JBBF Module rather than the IHKA Module, so if you have INPA, run Functional Jobs, Fault Memory (Fehlerspeicher) ALL Modules, and then connect to IHKA and read ALL codes with Definitions & FF Data/Details. Do the same for the JBBF Module, as the Compressor Valve and Refrigerant Sensor are connected to the JBBF, and some A/C system faults are in JBBF rather than, or in addition to, the IHKA Module.

If you have INPA and/or Manifold Gauges to Read High & Low Port Pressures (INPA just reads High Side Refrigerant Pressure Sensor pressure), I can suggest some tests. See the attached INPA Flap Positions Screen, page 6 of 10-page "IHKA Tutorial" pdf attached. The Rear Stratification Flap is the 2nd bar graph from bottom on Left column (to the Left of Front Stratification Flap.

THAT is NOT the issue if the Refrigeration Circuit does NOT produce cold air. The Rear Stratification Flap does NOT affect air temperature from ANY of the Front Vents. The Left & Right Mixed Air Flaps or Blend Flaps, which are controlled independently by the L & R Thermostats are the primary temp control for front vents, with Front Stratification Flap being a trim to adjust Face Level Temp.

If you have INPA (which is the BEST Climate Control Diagnostic I know of) the place to start is Readout Analog Inputs/Ports, with a sample screen shown on page 5 of attached pdf.

1) Note the Refrigerant Pressure Sensor readout at Bottom Left (Druck Kaltemittel). Static when high & low side are at equilibrium (after several hours shutdown) should be 6 to 7 bar (one bar = 14.5 PSI), and if the Compressor Valve is activated with motor running, that pressure should increase > 12 bar, depending upon charge, ambient temp, condenser air flow, etc.
2) Note the Evaporator Temp Sensor, 2nd from Bottom on Right. When Compressor Valve is active (compressor pumping) and expansion valve working, that temp drops to 10C or BELOW.

If you are getting refrigeration (High side > 12 bar & Evaporator Temp < 10C, then if you are NOT getting cool/cold air from the vents, your blend flaps are the next thing to look at. The Left & Right Blend or Mixed Air Flaps should be in the "0" position at coldest Thermostat settings. In that position, NONE of the air that has been cooled by the evarporator coil is directed through the heater core.

Please let us know what you find,
George

[dpaul]

Originally Posted by gbalthrop

Please Define "Stopped Working." That covers a LOT of territory:.

The Rear Stratification Flap does NOT affect air temperature from ANY of the Front Vents. The Left & Right Mixed Air Flaps or Blend Flaps, which are controlled independently by the L & R Thermostats are the primary temp control for front vents, with Front Stratification Flap being a trim to adjust Face Level Temp.


George

Very good points George but I actually had the experience that a short in the wires for the rear strat potentiometer caused all the flaps to move to heating position. Further, the only code I can remember recording was 9C69, although it was quite a while ago. I did not spend the effort to understand why, I just fixed the connector and moved on.

However, I didn't notice that the OP actually had 8 faults but only reported 3. Inexplicable! And he doesn't even tell us what the vehicle is!

[gbalthrop]

Originally Posted by dpaul

... I actually had the experience that a short in the wires for the rear strat potentiometer caused all the flaps to move to heating position. Further, the only code I can remember recording was 9C69...

If you had either a short or open circuit in the LIN BUS (Yellow/whatever) wire at the Rear Stratification Flap Motor Connector, then that WOULD prevent activation of any of the Flap Motors "Downstream" or to the RIGHT of the Rear Strat Motor (M4723), which include the Right & Left Mixed Air (Blend) Flaps. So if the default position is Full Heat (100%), then that WOULD result in heat from all front air vents, as the IHKA module could NOT close off air delivery through the heater core. Here is the TIS circuit for your 2009 E90 335xi:
https://www.newtis.info/tisv2/a/en/e...bution/uZS1ONq

It would be interesting to know WHAT the algorith for setting "9C69" is. I was thinking of it in terms of feedback to the IHKA Module NOT reflecting change of position due to faulty motor, BUT I have seen reports of similar flap codes resulting from open circuit in the LIN BUS wire/connectors.

So I SHOULD have qualified my statement: Rear Stratification Flap Motor failure does NOT affect front air vent temp UNLESS the LIN BUS Series Connections are disrupted. AFAIK, a fault in the power supply, ground, or motor itself, which does NOT affect the LIN BUS Yellow/whatever wires, would NOT affect operation of flap motors "Downstream." Anyone with a different concept?

Thanks,
George

[dpaul]

Originally Posted by gbalthrop

If you had either a short or open circuit in the LIN BUS (Yellow/whatever) wire at the Rear Stratification Flap Motor Connector, then that WOULD prevent activation of any of the Flap Motors "Downstream" or to the RIGHT of the Rear Strat Motor (M4723), which include the Right & Left Mixed Air (Blend) Flaps. So if the default position is Full Heat (100%), then that WOULD result in heat from all front air vents, as the IHKA module could NOT close off air delivery through the heater core. Here is the TIS circuit for your 2009 E90 335xi:
https://www.newtis.info/tisv2/a/en/e...bution/uZS1ONq

It would be interesting to know WHAT the algorith for setting "9C69" is. I was thinking of it in terms of feedback to the IHKA Module NOT reflecting change of position due to faulty motor, BUT I have seen reports of similar flap codes resulting from open circuit in the LIN BUS wire/connectors.

So I SHOULD have qualified my statement: Rear Stratification Flap Motor failure does NOT affect front air vent temp UNLESS the LIN BUS Series Connections are disrupted. AFAIK, a fault in the power supply, ground, or motor itself, which does NOT affect the LIN BUS Yellow/whatever wires, would NOT affect operation of flap motors "Downstream." Anyone with a different concept?

Thanks,
George

LIN bus fault makes sense to me. It's just that you'd think the system would be smarter about reporting the nature of the fault.

[DCook]

Ive been quite busy with work, and other mechanical stuff.

Sorry im not a very bright crayon so please bear with me. I'll try to answer the best i can, as im not as informative and up to date on the functionings of the way the cars work electrically.

Car is a 2008 e92 335i n54 single turbo 6 speed.

The other codes up, are not important and irrelevant. Right wheel speed sensor, steering angle sensor, and tpms related due to aftermarket wheels and removal of tmps in general.

The a/c always worked beautifully until i left work one day, and i just started throwing parts at it, before pulling up codes, inpa, etc. Thats why i replaced the compressor and exp valve. But i read exp valves go bad so figure it wouldnt hurt.

Then later decided to pull codes and got the one posted above.

Okay, so, even with the temp knobs on max cool, during driving, it still feels like regular max heat is coming out of all vents. I have access to inpa, all the flaps are functioning other than the rear stratification Fond [only e9x] it stays on 0. The rear flap i can feel functioning with my finger on it. Ive even replaced and auto addressed in inpa. But does not function with the rear potentiometer. Only when you press the footwell/floor vent does it function. But does not change Fond, only footwell in inpa.

Now, i literally pulled the console up, removed all the tessa tape, and have seperated the wires from the rear console to the actual module under the dash. There is no wires crushed or pinched or damaged at all. Replaced rear strat adjuster as well to be sure.

Evaporator temperature is 30-38* C in inpa. I do not have a set of full a/c gauges handy at the moment. I will pickup a set when time allows. Just your basic parts store hand held filling with gauge.

Im really unsure what to do at this point. Its not enjoyable to drive the car in 80-100*F weather with no a/c. Because the way i understand bmws thinking, is if the rear stratification flap isnt working, functioning, the entire a/c system wont function. Now, if i can find a way to code out, or remove the rear strat flap, i gladly will. Im the only person in this car 95% of the time. No rear passengers. No need for rear strat/flap.

Codes asked for through inpa for all modules.
Jbbf = 9c69
Dme = 2c9e
Rdc = 604f - 6050 - 605e
Frm = a8c5 - a8c2 - a8c1

Thats it on that as an all read error memory

Just doing junction box is the 9c69.

If i do auto addressing i can get Fond [only e9x] in inpa to go from 0 to 100.

I go to msd81 - component triggering - actuator activation - clima compressor relay - its already on, so the compressor should be active, yes?

Refrigerant pressure sensor [druck kaltemittel] is at 0. [ print cooling agent] on my inpa.
Bad refrigerant sensor then??

Im updating this as i try and read each question, edit and reply.

[DCook]

Alright i digged more into this. I forgot to mention every once in a while it would throw a pressure sensor code from the junction box. I only assumed it was because the system would activate the system but didnt build pressure, so it thre the code and brushed it off.

So, i looked into where the high pressure sensor was, and found the wires by the single turbo exhaust housing were melted completely to bare copper and then some. Also, the other two wires in that area are for the right front wheel speed sensor. Which is odd, as the other codes thrown are for the rear right speed sensor. I figure because it was caked in grease from a bad boot, and wrote it off.

Needless to say, pulled the turbo blanket off, cut all the wires and crimp and heat shrink and re routed them away from the heat, and the a/c system works great, no more dsc/angle sensor/junction box potentiometer codes. So, weirdly enough the same codes that are thrown for the rear stratification potentiometer, are used other areas too, maybe its just a junction box potentiometer signal receiving error that gets thrown in general? It had nothing to do with the interior rear.....what a crazy chase.