RX450H B15D0 fault

[ChrisM]

I had to have my auxiliary Battery changed as it had died. Called he AA and they diagnosed a sick Battery. ignorer to get to the Battery I small Battery was attache to the positive and negative attachment points in the fuse book in the bonnet. this allowed to unlock the power tailgate to get access to the Battery. This was diagnosed as faulty. No 3rd party batteries were available so had to bite the bullet and get Lexus  Gatwick to fit a Lexus supplied one. This was fitted by them and cost £236.

I now have problems using the sound system (Mark Levinson) and the cursor control system for Sat Nav and setup etc. I have access to Techstream so checked and found A B15D0 fault MOST Communication Malfunction. Looking this up has pointed to amplifier failure, short in speaker wires. 

i found an article that spoke about switching on the engine with the radio switched on and to fix it i should put the car on auxiliary without starting the engine then switch the radio off. This i tried, switching to auxiliary gave me my audio system and cursor control back. However when i turned the radio off followed by starting the car, I lost audio and cursor again.

I am guessing that replacing the Battery has upset something. MOST seems to use fibre optics to communicate. Does anyone have info on where these optics are and if could be affected by Battery replacement. I hate the idea of going back to Lexus and paying even more to fix something that they may have done.

Any help is appreciated.

 

 

 

 

 

[royoftherovers]

Anything within your Handbook Chris about resetting  equipment ?

[Herbie]

52 minutes ago, ChrisM said:

I have access to Techstream so checked and found A B15D0 fault MOST Communication Malfunction. Looking this up has pointed to amplifier failure, short in speaker wires. 

So thinking logically, you've had the Battery replaced and now you've got a fault that suggests a short circuit in one of the speaker pairs.

What does that tell you?

Maybe they trapped the wires when putting the new Battery in place?

No amount of fiddling with the radio switch or messing about up front is going to sort out a physical short circuit, so take the Battery out and examine any wiring in or around that area as a first step and let us know how you get on.

[08ISF]

If it was OK before they fitted the Battery and it's not now, then that points to something that needs resetting post Battery change. Lexus techs should be familiar with all the resetting procedures  and they should have checked that everything works before returning the car. I'd go back to them and resist any requests for extra money. It would help to first make the checks suggested in the previous post  though.

[Zotto]

If it is not a short circuit on speaker wires, try resetting navigation keeping the switch (volume knob) pressed for some seconds; it should reset navigation system.

[Barry14UK]

First I've heard mention of fiber optics but certainly removing/replacing the 12v Battery can result in loss of sync of certain things and require to be re-coded. Lexus Gatwick should be aware of this.  I would contact them and if they are unable to successfully talk you through a procedure ask them to fix it FOC. 

 

 

 

 

 

 

 

 

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[OzoneSal]

Hello I am on sure if you found a resolution to your problem but I have the same model RX450HA 2011 and I've on the for several months and have had nothing but problems with the audio system navigation As well as backup camera The code is the same B15D0 and I have retrieved it and reset it through a procedure of turning the headlight yoke knob on and off 3 times as you press the menu button near the touch cursor. This will put you in an informative diagnostics.  I've tore down the interior upon a past water problem from dammed up rear clam shell tailgate trim plastic collecting pine needles and depositing water in Battery tray which then would roll foward to rear seat  2nd row foot well.  Luckily no issues with hybrid  Cleaning and Reconnecting any suspect connections from front to back. It can work for several days or not work for several days regardless of freezing or extreme heat.  Unsure if a new radio or amp will resolve or if it really is an intermittently bad speaker.  I don't know of any fiber optics  all connectors I've located were standard wiring.  Good luck if this helps you more than me. Keep me in the loop if you resolved yours.  🍻 Cheers from OzoneSal