"Check trailer lights" on dash, but no trailer attached

Wahnsinn · 09-06-2017, 03:36 PM

I have a light on my dash saying: „check trailer lights“ (CC-7), but I have no trailer attached. The car is an E91 325 2005 with the hidden hitch (S3AC). The light pops up, when I switch on the lights. The indictors blinking frequency rises sharply after two blinks as if one indicator was faulty.

I have read the error memory of the AHM module and the information memory using INPA. The error memory is empty and the information memory says that all trailer lights malfunction. (Error Codes: Fehler 9401 AHM,9405 AHM, 9400 AHM, 9403 AHM.)

The issue occurred for the first time after pulling a trailer for 200km.
Any ideas how to fix this? Can anyone help?

torbmw · 10-22-2021, 04:06 PM

Did you ever figure out the cause of this problem? I have the same issue on my 2006 330i.

Andystobbs · 10-22-2021, 04:42 PM

Check for water ingress at AHM

09-06-2017, 03:36 PM	#1
Wahnsinn Registered 0 Rep 2 Posts Drives: E91 N52B25 Join Date: Aug 2017 Location: Germany iTrader: (0)	"Check trailer lights" on dash, but no trailer attached I have a light on my dash saying: „check trailer lights“ (CC-7), but I have no trailer attached. The car is an E91 325 2005 with the hidden hitch (S3AC). The light pops up, when I switch on the lights. The indictors blinking frequency rises sharply after two blinks as if one indicator was faulty. I have read the error memory of the AHM module and the information memory using INPA. The error memory is empty and the information memory says that all trailer lights malfunction. (Error Codes: Fehler 9401 AHM,9405 AHM, 9400 AHM, 9403 AHM.) The issue occurred for the first time after pulling a trailer for 200km. Any ideas how to fix this? Can anyone help?
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10-22-2021, 04:06 PM	#2
torbmw Registered 0 Rep 3 Posts Drives: BMW E90 330i 2006 Join Date: Oct 2021 Location: United Kingdom iTrader: (0)	Did you ever figure out the cause of this problem? I have the same issue on my 2006 330i.
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10-22-2021, 04:42 PM	#3
Andystobbs Captain 196 Rep 720 Posts Drives: E91 Lci, Vectra B V6 Join Date: Sep 2019 Location: Chester, South Wirral iTrader: (0)	Check for water ingress at AHM
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