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E90 CAS Issues

5620 Views 16 Replies 6 Participants Last post by  Ferragamo_n54
2009 E90 sedan. the car runs great, but after turning up the gain on my amplifier, a little bit of time passed then the car began shutting off on me with no warning. For example I was in a drive through and the motor shut off as i went to drive away. it didnt bog down, or run rough. Almost as if someone had pushed the button to turn it off. the car also will be driving, and feel as if it downshifts hard for no obvious reason.

Car is running fine, but does have a bad o2 sensor after the cat.

Using a foxwell scantool i've pulled some codes.
A0A9: CAS Control unit fault
A0BE: CAS terminal 15 output 1
A0BF: CAS terminal 15 output 2
A0C0: CAS terminal 15 output 3
A122: CAS short circuit hall sensor
A123: CAS short circuit hall sensor

9CAB: FRM: one terminal 15 missing

and i got a new type of code appearing, A3B2:Message Error (terminal statues 0x130), receiver instrument panel transmitter CAS. There was one similar but it accidently got cleared before i could write it down.
the codes in bold stuck around/came back almost immediately after clearing them, car was running at the time.

Any Idea of what I should do? or a starting point? I've loved this car but if this gets anyworse i might have to sell it.
Any help is appreciated. thank you in advance
1 - 17 of 17 Posts
MFG date and engine will be required to provide the correct information. It matters.........

But until then, in general, the CAS provides Terminal 15 power to other consumers via the Junction Box, when the key is present AND the start button is pushed. The electrical wiring of Terminal 15 is rather complex, so I will wait until you provide the info about your vehicle.
Motor is the n52 and MFG DATE is 05/2009
Exactly what power source and/or fuse do you have your audio amplifier connected to?

If you are pulling power from any source using Terminal 15, then you may need a new CAS module...ensure that your amplifier is wired directly from Fuse 42 (40A) powered by Terminal 30.

Take your amplifier off line, then post if your car recovers it's proper operation.....if so, then let's wire up your amplifier correctly in your vehicle...on the other hand, if your car does not recover after removing your amplifier, you may need to seek professional help.

Although "red" wires may be in the vicinity of your amplifier location, it's almost never OK to tap them for +12VDC...

What is your battery voltage when the car is off, when the car is in accessory mode, but engine not running, and when the car engine is running?
ALL of the Fault Codes you list, including the KOMBI Message Error, NO Message from CAS, COULD be caused by interruption in the CAS Power Supply. They could also be caused by an internal fault in the CAS Module, but always start with the cheap, simple stuff, in this case fuses: F36 (40A) & F55 (5A). Attached are ISTA wiring diagram and Fuse Locations for F36 & F55.

If the symptoms happen again, listen carefully for "Click" or even "Chatter" (ratchet-like repeated clicking) from the glovebox area, which would suggest KL15 relay contacts failing to remain closed. The KL15 relay is soldered to JB PCB, rather than plug-in, but I can't recall a knowledgeable report of failure of that relay. The Connector (X11010/6) is therefore 1st suspect.

The CAS Module Activates the two Relays, shown as IO1068 ("Accessory" or 30G Relay) and IO1069 (KL15 or Ignition Relay) on the attached wiring diagram. The KL 15-3 circuit powers the Headlight Switch related to FRM, hence the FRM code. So if CAS Power Supply is interrupted, as you describe Ignition is turned off, same as if you pressed STOP. The fact that it is just momentary suggests a loose or corroded connection, perhaps at the fuse panel, or at the CAS Connector X13376, or an internal fault, such as a cracked solder joint, in the CAS PCB (Printed Circuit Board).

I would begin by removing the two CAS fuses, & cleaning the fuse spades and sockets. Sockets are "Live" on one side as both are UN-switched battery power (KL30) as indicated by the small "30" over each fuse symbol on the SSP. If symptoms persist, I would disconnect X11010 at the top-left of JB (Junction Box) Fuse Panel, and carefully inspect pin & Socket related to Pin #6, Green Wire, as that is KL15 Activation wire from CAS Module.

If you had INPA or ISTA, you could view the voltage of ALL of those Terminals and the Hall Sensors as Live Data. Probably would NOT add that much however, as the fault codes tell the story rather clearly if you understand the circuits involved.
Anyone know what the two "Hall Sensors" (12 & 34) in the INPA "Diagnose Terminals" Screen relate to?

If you have had any water in either footwell lately, let us know. Wet/corroded fuses or connectors, or even a bad ground, COULD cause the issue. Any work, such as Blower Harness Recall, been performed in either footwell recently? No wiring changes or changes in Amp wiring?
George
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Amplifier power was run off of the battery with an in line fuse, the picture shows where I ran my positive from.
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I also ran my remote wire off my stock amplifier, i just tapped the wire.
It is now disconnected. I'll be checking the voltages tonight and posting
Exactly what power source and/or fuse do you have your audio amplifier connected to?

If you are pulling power from any source using Terminal 15, then you may need a new CAS module...ensure that your amplifier is wired directly from Fuse 42 (40A) powered by Terminal 30.

Take your amplifier off line, then post if your car recovers it's proper operation.....if so, then let's wire up your amplifier correctly in your vehicle...on the other hand, if your car does not recover after removing your amplifier, you may need to seek professional help.

Although "red" wires may be in the vicinity of your amplifier location, it's almost never OK to tap them for +12VDC...

What is your battery voltage when the car is off, when the car is in accessory mode, but engine not running, and when the car engine is running?
Car off:12.83 - 12.85
Car running 14.67 -14.71
Accessory mode:12.38 - 12.34 (seemed to wanna keep going down. Car has not died while sitting overnight)
Exactly what power source and/or fuse do you have your audio amplifier connected to?

If you are pulling power from any source using Terminal 15, then you may need a new CAS module...ensure that your amplifier is wired directly from Fuse 42 (40A) powered by Terminal 30.

Take your amplifier off line, then post if your car recovers it's proper operation.....if so, then let's wire up your amplifier correctly in your vehicle...on the other hand, if your car does not recover after removing your amplifier, you may need to seek professional help.

Although "red" wires may be in the vicinity of your amplifier location, it's almost never OK to tap them for +12VDC...

What is your battery voltage when the car is off, when the car is in accessory mode, but engine not running, and when the car engine is running?
No water in footwear or anything near recently, and no recent work or changes other then me unhooking the amplifier. I didn't do it to me today, which makes me hopeful, but I also didn't drive very much. Both of the fuses you had me check are not blown. I also do have access to inpa if that would help. And nothing notable about pin #6 or the connection
ALL of the Fault Codes you list, including the KOMBI Message Error, NO Message from CAS, COULD be caused by interruption in the CAS Power Supply. They could also be caused by an internal fault in the CAS Module, but always start with the cheap, simple stuff, in this case fuses: F36 (40A) & F55 (5A). Attached are ISTA wiring diagram and Fuse Locations for F36 & F55.

If the symptoms happen again, listen carefully for "Click" or even "Chatter" (ratchet-like repeated clicking) from the glovebox area, which would suggest KL15 relay contacts failing to remain closed. The KL15 relay is soldered to JB PCB, rather than plug-in, but I can't recall a knowledgeable report of failure of that relay. The Connector (X11010/6) is therefore 1st suspect.

The CAS Module Activates the two Relays, shown as IO1068 ("Accessory" or 30G Relay) and IO1069 (KL15 or Ignition Relay) on the attached wiring diagram. The KL 15-3 circuit powers the Headlight Switch related to FRM, hence the FRM code. So if CAS Power Supply is interrupted, as you describe Ignition is turned off, same as if you pressed STOP. The fact that it is just momentary suggests a loose or corroded connection, perhaps at the fuse panel, or at the CAS Connector X13376, or an internal fault, such as a cracked solder joint, in the CAS PCB (Printed Circuit Board).

I would begin by removing the two CAS fuses, & cleaning the fuse spades and sockets. Sockets are "Live" on one side as both are UN-switched battery power (KL30) as indicated by the small "30" over each fuse symbol on the SSP. If symptoms persist, I would disconnect X11010 at the top-left of JB (Junction Box) Fuse Panel, and carefully inspect pin & Socket related to Pin #6, Green Wire, as that is KL15 Activation wire from CAS Module.

If you had INPA or ISTA, you could view the voltage of ALL of those Terminals and the Hall Sensors as Live Data. Probably would NOT add that much however, as the fault codes tell the story rather clearly if you understand the circuits involved.
Anyone know what the two "Hall Sensors" (12 & 34) in the INPA "Diagnose Terminals" Screen relate to?

If you have had any water in either footwell lately, let us know. Wet/corroded fuses or connectors, or even a bad ground, COULD cause the issue. Any work, such as Blower Harness Recall, been performed in either footwell recently? No wiring changes or changes in Amp wiring?
George
View attachment 1053980 View attachment 1053981 View attachment 1053982 View attachment 1053983
Thanks to [COLOR=rgb(49, 130, 233)][B][SIZE=4]M_Bimmer[/SIZE][/B][/COLOR] and gbalthrop for the help. Car no longer has the fault codes, thankfully something we did fixxed it, I'm keeping the amplifier disconnected until I can plan a better system. Thank you guys for the help
Updating so if anyone has similar issues
I noticed if I wiggle my key fob while the car is running, sometime it will trigger it to shut off, it's more rough then what the car does by itself. So I'm gonna be replacing the key fob reader and seeing what it does for me. The terminal 15 codes came back. I believe these are the same ones that it kept bringing back up

A0BE: CAS terminal 15 output 1
A0BF: CAS terminal 15 output 2
A0C0: CAS terminal 15 output 3
Stereo Board on e90post reports that you will start to have electrical problems when running
aftermarket stuff over 2000 watts. I have been running a JL 600/6 for years with not problems
but it is only a 600watt amp that probably runs at much less than that. Also it's hooked up to the
battery tightening lugs with 04 wire.
The amp I was running was not very powerful, at most 500 watts running to 2 twelves
Stereo Board on e90post reports that you will start to have electrical problems when running
aftermarket stuff over 2000 watts. I have been running a JL 600/6 for years with not problems
but it is only a 600watt amp that probably runs at much less than that. Also it's hooked up to the
battery tightening lugs with 04 wire.
welp. back to square one. i think there is a clicking sound coming from my cas module, or fuse box.
Updating so if anyone has similar issues
I noticed if I wiggle my key fob while the car is running, sometime it will trigger it to shut off, it's more rough then what the car does by itself. So I'm gonna be replacing the key fob reader and seeing what it does for me. The terminal 15 codes came back. I believe these are the same ones that it kept bringing back up

A0BE: CAS terminal 15 output 1
A0BF: CAS terminal 15 output 2
A0C0: CAS terminal 15 output 3
Did you ever get this fixed? I am having the same issue on my 07 335i
Me 2 did you figure it out?
Did you ever get this fixed? I am having the same issue on my 07 335i
Do Forum Search on "same issue/problem".:eek::rolleyes:
Or, see this post and start NEW thread with info requested.
George
Me 2 did you figure it out?
I ended up using ECU maverick. I sent them my cas unit and they rebuilt it and shipped back was $200 seemed like a fair price. I haven't had any issues since rebuild and it's been over a month
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