After Long Drive No air in cabin.
After a couple of long drives from Seattle to Cali back to back I experienced a problem on both drives. After about 8hr drive or so the air would decrease to almost non existent to the cabin. But you can hear the fan working, and does change speeds when you press recirculate, etc. After shutting the car off for a few minutes the air would once again fill the cabin then slowly the air in the cabin would die down.
So this last trip, I brought it to a shop and we replaced the fan resistors and fan. Took the trip back home to Seattle, and it happened again. So I did some research, and could only find bits an pieces of information.
1. Some claim that it could be just low on freon....
2. Evaporator is freezing up, and an humidity sensor needs to be installed. possible Bulletin on this, but dealership can't find one.
3. Dealership states it's possible that it's the solar/sunload sensor on the hood not properly reading, causing flaps not to close.. etc.
Did anyone ever get a solid answer to a solution to this?
Also the diagnosis menu on the climate control unit, does anyone have a value data?
Most that I can find applies to an older model control unit. Another is, does anyone know how to switch the climate control unit to fahrenheit? Thanks in advance
How long has it been doing it for?
On a side note I have had too install resistors in the evap temp sensor line to adjust temp reading on other models before but that is a extreme case and think its prob something more simple.
After a couple of long drives from Seattle to Cali back to back I experienced a problem on both drives. After about 8hr drive or so the air would decrease to almost non existent to the cabin. But you can hear the fan working, and does change speeds when you press recirculate, etc. After shutting the car off for a few minutes the air would once again fill the cabin then slowly the air in the cabin would die down.
So this last trip, I brought it to a shop and we replaced the fan resistors and fan. Took the trip back home to Seattle, and it happened again. So I did some research, and could only find bits an pieces of information.
1. Some claim that it could be just low on freon....
2. Evaporator is freezing up, and an humidity sensor needs to be installed. possible Bulletin on this, but dealership can't find one.
3. Dealership states it's possible that it's the solar/sunload sensor on the hood not properly reading, causing flaps not to close.. etc.
Did anyone ever get a solid answer to a solution to this?
Also the diagnosis menu on the climate control unit, does anyone have a value data?
Most that I can find applies to an older model control unit. Another is, does anyone know how to switch the climate control unit to fahrenheit? Thanks in advance
I experienced the same issue, dealer came back with NTF (no trouble found) and not low on freon, their next suggestion was to replace the control module (I think the dash display) at a $1500 cost, they did not even know if this would fix the issue
I think this is a hard one to diagnose since it happens many hours after operation. This I just recently found out since the past two months was the longest I took the car for a drive. Other than that it's been 4-5hrs max, my last few drives have all been in the 12-24hr drives, and have all occurred during these longer trips.
I really stuck here, since my Dealership denies any information on this matter, the only thing they come close to is the Sunload sensor, which I am willing to replace if I can get more info on how and what connection it has to the problem. I have also ordered a new ambient temp sensor, just to be certain that sensor is isolated since it's a pretty cheap sensor.
How long has it been doing it for?
On a side note I have had too install resistors in the evap temp sensor line to adjust temp reading on other models before but that is a extreme case and think its prob something more simple.
LMK how you get on, I agree it's really hard to diagnose, when I stopped for a bite to eat (30 mins) during on of my trips all seemed to work fine after
Mine does the same thing, it will work fine after having the car off for 30+mins. This would seem to explain something freezing, or overheating and then thawing or cooling off.... This is why I want to find out about the sunload sensor and see what play it has, since my dealer is suggesting it's that.
I am not saying my dealer is wrong, I have to give them credit for taking the time to research and make conversation, also the fact that they do not have the car in hand. But since I know they will not be able to duplicate this matter, I figured I would give them a call and see if they have come across anything like this, or have been briefed about this issue before.
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sun sensor, is 100% BS
Last edited by Yacht Master; Jun 26, 2013 at 08:03 AM.

If in doubt always blame the other guy,
If in doubt always blame the other guy,

The port is in the back right part of the engine bay (driver's side) close to where the ECU is.
There are members here to assist, just short on memory as to how to access the menu on your model.
For the 05-06 model's we hold the driver side AUTO BUTTON feature for 10 second's.
Once Climate Control Data menu pops up, use the driver side TEMP UP & TEMP DOWN for toggle.
Sorry for the cut and paste but it was an easy search 06 E55 AC menu





