Central Locking/Alarm/Key Fob issues. Please Help
05-01-2022, 07:31 PM
#21
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My Ride: 05 530i M54
Model Year: 05 530i
Engine: 3.0 M54
You can easily check which module is bad by installing a MOST loopback. If you think it's the TCU then I usually install before and after to isolate the module and I know for sure I have the right bad module. They are a few dollars on Amazon and a good troubleshooting tool. If you decide to get one make sure it has the male and female loopback included.
If your TCU is bad then you do not necessarily need to code it but it's best to depending on the options you have on your car. All that needs to happen is a VIN program (so your Bluetooth matches the car) and default code it (to ensure your VO is coded correctly). I usually update the module also since I'm changing the VIN. You can find a TCU in the junk yard fairly cheap. The last one I bought was $20. Just know, when or if you code the TCU, the changes may or may not take immediately. Sometimes you have to let the car go to sleep for the changes to take. I let it sit for a couple hours then it's fine.
If your TCU is bad then you do not necessarily need to code it but it's best to depending on the options you have on your car. All that needs to happen is a VIN program (so your Bluetooth matches the car) and default code it (to ensure your VO is coded correctly). I usually update the module also since I'm changing the VIN. You can find a TCU in the junk yard fairly cheap. The last one I bought was $20. Just know, when or if you code the TCU, the changes may or may not take immediately. Sometimes you have to let the car go to sleep for the changes to take. I let it sit for a couple hours then it's fine.
05-02-2022, 04:03 AM
#22
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Thank you very much for all the info. So in fact the TCU can be bad while the MOST loop continues through the unit? And a bad TCU can be the problem with my locking issues?
05-02-2022, 05:59 AM
#23
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My Ride: 05 530i M54
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I've never heard the TCU causing issues for the locking system. The alarm is controlled by the DWA module on the K-CAN not MOST network. It receive signals from the CAS which manages your locks. That's usually the diversity antenna depending on what issues you're actually having.
05-02-2022, 10:07 AM
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Thats correct it was mostly wishful thinking. My best guess was the diversity antenna based on symptoms but since I have no codes showing up anywhere just the one CCC-Gateway code and nothing towards the diversity antenna I’ve kind of strayed away from what is probably my problem. Should I give it more time for codes to reappear as I cleared all codes a week ago?
Wife drives the car a couple miles each day and ive been scanning for codes every evening
Last edited by rtreyna; 05-02-2022 at 10:12 AM.
05-02-2022, 10:31 AM
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My Ride: 05 530i M54
Model Year: 05 530i
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The antenna gives a signal to the CCC via ant_FM. Is your CCC completely down? If so TS your CCC (quickest way is to install the loopback) and see if everything comes back up.
Let me ask was something removed from the car. I just remembered seeing that code once before and it was due to an open loop because a module was removed.
Let me ask was something removed from the car. I just remembered seeing that code once before and it was due to an open loop because a module was removed.
Last edited by seanjordan20; 05-02-2022 at 10:45 AM.
05-02-2022, 12:02 PM
#27
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No nothing has been removed. I did notice a MOST connector that is free by itself along with what looks like an antenna fitting in the trunk where TCU and Amplifier are but I think that is for satellite radio option(or other component) which my car never had. There is no light going to that MOST connector.
05-02-2022, 12:07 PM
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The only thing I have ever done electrical wise to the car was add a line output converter for aftermarket sound system. I tapped into the rear speaker wires in a bundle of wires in the trunk. But that was back when I first got the car and all was well afterwards
05-02-2022, 12:11 PM
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What would I be experiencing if CCC was completely down? Everything I know that does not work is as follows. 1. No remote locking with key fobs. 2. No locking/unlocking of passenger doors via double turn of manual key in driver door. 3. No arming or disarming of alarm when locking and unlocking car. 4. Voice commands do not work(never have) 5. Some of the windshield wiper speeds and adjustable intervals dont seem to work.