Topic: Have one Foxwell NT520 scanner for BMW E60 2007 530i IHKA (ac and heat controls) scan.
I see a readings that states Outside Temperature 32 (image 1)
the Auxillary heater temp is 32 and is always 32.
AMBIENT TEMP 94 (image 2)
a trouble code not sure it this is related or not. (image 3)
Advice by friend:
Disconnect the sensor Oldie pointed out and see which reading changes. Check connector for corrosion also. Also, if possible, check the number of wires the sensor/connector has. If there are more than 2, the sensor may really be (2) sensors, (1) for the cluster, (1) for the IHKA.
The AC evaporator has a temp sensor that will turn the compressor off if it detects a freezing evaporator. If this fails or sends a faulty temp due to bad connection compressor will turn off. Evap temp should be ~34F range w/AC running.
I assume that the evaporator temp will be in the 34F range if I have the temp set super low (dials all the way counter clockwise). If I have it set to say 72 then evap temp will fluctuate as the systems cools the cabin as needed? Do I have that right?
As long as the AC is on and functioning properly the evaporator should be 34F all the time. It may get a little warmer at idle but on the highway it should be close to 34F. All air passes thru the evaporator and then the heater core in series. The heater valve regulates water flow to the heater core to maintain the interior temp you set with the dials. If something turns the compressor off, then evap temp will rise.
Here’s a good description of the IHKA including the sensors.
Failed fan prevents AC condenser from working, which raises high side pressure and will open the relief valve on compressor if the high pressure switch doesn’t shut system down. Condenser fan failed on my E39. Startled the hell out of the elderly couple in the parking lot.
My E60 takes a while to cool down on occasion. I suspect the capacity control valve in the compressor is sticking or stuck. But it’s been fine for several weeks now. Running AC in recirc mode will help improve cooling because you’re not dehumidifying 100% outside air, mostly interior air that has already been dehumidified. Looking at evap temp during a drive will tell us if there is a problem or not.
Can the solenoid valve, I assume this is the one on the compressor itself, be swapped ? I should say the capacity control valve which I assume is a fancy solenoid valve of sorts.
The capacity control valve is a replaceable part. About $60 on ebay. You need to remove refrigerant, replace valve and recharge.
This is IHKA e60 test results
I went out yesterday and was able to get some additional information:
– Ambient temp was 87-91F; at 11:00am, I live in Fl so pretty normal temps
before starting car:
-low and high pressure gauge put on car, pressure was equalized ~95-100psi
-obviously Evap temp was hot, 87F;
-shortly after starting car, with AC on auto and auto recirc on, low pressure 40PSI high pressure 235PSI. I feel pretty normal operation and the car was warming up, and the AC compressor starting working, pressure would fluctuate from 30PSI – 250PSI from time to time as I think the compressor was working.
-Evap temp went quickly to 57F; and then worked down to 50F; in about 3-4 minutes. This is with all 4 door open so temp in the cabin never really went down but the vent felt cold. Wish I would have purchased a temp probe but didn’t have one at this time.
-Let car run for a while in this condition, low and high pressure would fluctuate, air felt cold coming out of vents and evap temp would move around from 48-52F;.
closed doors on car getting ready to go for a ride
-disconnected gauges from low and high pressure and closed door and windows getting ready for a ride and while getting ready notice that the evap temp was dropping. This is still while car is in drive way and I haven’t moved yet.
-So I let car side at idle with door windows closed. Cold air out of vent and evap temp kept dropping down to 32F;. So I felt real good about that.
took car for a ride
-cold temps out of vents and evap temp remained at approx. 32-36F; the entire time, high speeds and low speeds as well. Not traffic as it was a Saturday.
returned home and let car sit still simulating traffic
-Sat car in direct sunlight in driveway while not moving, door windows up. Cold air out of vents and evap temp remained 34-36F;. Left car like this for about 15 minutes and all seemed to work well. Low and high side pressures all looked about correct, ~35-225.
-Decided to open doors and run ac
-once I opened the door and left them open, evap temp rose to 50F; while vents still felt cold. Once again I closed door and within a couple minutes evap temp dropped to 34-36F;.
I also recorded 3000 data points sitting in my driveway and for the drive I took using my scan tool of the IHKA system, outside temp, evap temps, fan control etc. I haven’t looked at this in detail as of yet, I mean there are 3000 data streams and each one has about 20 different values so lots of data.
At this point, it seems the AC system is working correctly at least to me. If you feel otherwise PLEASE let me know. I am no expert and would appreciate any input at this time.
What I FEEL is happening:
Florida is hot and the sun is real bright, I think most of you know that. This was my wife’s car and I just inherited it as she got a new non-BMW vehicle. I didn’t drive it much.
On my way home Friday, bright sunshine, evap temp 36F;, cold air out of vents, I still felt hot. I realized is was coming from the window side of the vehicle and sun was beating on my left side heating me up. Car DOES NOT have window tint. She didn’t want it for backing up, hard to see. I think the sun is heating up the car and the persons in the car. All my other vehicles have always had tint so I never noticed this before. Maybe I am crazy but it seems like all the values are in range on the car.
Keep a thermometer in the center vent and keep an eye on temps while you drive, but it looks like the AC is working well. I don’t see any issues. Not clear the original problem has disappeared.
What’s happening to the sensor in your first post that was reporting 32F while the AC is working well?
If the IHKA believes outside temps are <40F, it will prevent AC operation. I don’t know for certain but it may also adjust vents to avoid blowing what it believes to be cold air in your face.
What about your suggestion?
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For your information, Foxwell NT530 BMW scanner will be better than Foxwell NT520 since it can access to all BMW F series car models.