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The following is from a scan on the SL550 R231 for problems with the Airscarf system. Neither of the two buttons light up and nothing happens when they are pushed in.
From the scan, it looks like the Airscarf module is communicating with the scanner so I don't think that's the issue. The part I don't understand is the last line of the scan results. The module received an implausible outside air temperature at some point and shut itself off. Does this mean the module has locked itself out of operation? Does it have to be reset and if so how? Note that the outside sensor seems to be within operating range now.
Any help would be much appreciated.
The following is from a scan on the SL550 R231 for problems with the Airscarf system. Neither of the two buttons light up and nothing happens when they are pushed in.
From the scan, it looks like the Airscarf module is communicating with the scanner so I don't think that's the issue. The part I don't understand is the last line of the scan results. The module received an implausible outside air temperature at some point and shut itself off. Does this mean the module has locked itself out of operation? Does it have to be reset and if so how? Note that the outside sensor seems to be within operating range now.
Any help would be much appreciated.
Though the Airscarf module is communicating, it’s quite possible for the circuit of the module that communicates with the outside air temperature sensor has failed, or is not getting the signal from the CAN BUS either due to faulty connector or wiring. If the Airscarf has triggered a code, it should be cleared. You’re on the right path, as if it was just one side failing it would point to a switch.
I’ll see if I can find the WIS section on it next time I’m in my shop, probably tomorrow.
CR, thanks for the quick response!!
On the scan I see the outdoor temp at 17C so it looks like its being read. Is it read by the UCU and sent to the module by CAN? I would guess from your reply that this is true and the module has locked itself in a default off position. Is there a way to clear the fault without XEntry?
Just for the hell of it, I bought a used module off of EBay but I cant get near the car until April to try everything out. I will post when I get it done.
I would guess from your reply that this is true and the module has locked itself in a default off position. Is there a way to clear the fault without XEntry?
It is possible your scanner just isn't picking up the codes. What kind of scanner are you using?
Hi again CR! I'm using an XTool D8. Not ideal but suits my needs for a few cars.
Haha, well as the benzninja eloquently put it....
It may be an issue that that particular scanner isn't accessing all the diagnostic/testing functions of the AIRSCARF system. The screenshots I uploaded below are what you'll see in XENTRY, so you can compare screens with your scanner. (these are in simulation mode, so not complete). I'm going to assume your scanner has no access to the testing functions.
I can tell you that many times AIRSCARF issues are tied to the temperature sensors, but as with all things electrical, not always
I attached all the WIS sections pertaining to the AIRSCARF system. Might help locate some individual components.
Good Luck!
Last edited by crconsulting; Feb 15, 2023 at 12:44 PM.
Thanks CR, thanks for the XEntry screens, they are quite a good guide. I appreciate the help with WIS but I should have mentioned that I have it along with the parts list on a VM.
The scanner I have is actually quite good for a lot of my other cars particularly BMW. On the SL I have the ability to test all kids of SL systems as well as calibrate things like the front and rear cameras. However, the software is lacking for the Airscarf. Its nowhere as powerful as XEntry but it works for me.
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