SL/R230: MOST loop bypass
Thread Starter
Junior Member
Joined: Jan 2023
Posts: 15
Likes: 0
2006 SL500
MOST loop bypass
So I am getting a little more than frustrated with the issues that I am having getting my new aftermarket head unit to work with my Bose MOST system. 2006 SL500. Audio will work...from time to time. But once I get it to work, and I shut the car off, it will not work when I turn it back on. I verified that the head unit is ok, by running the RCA connectors to my garage stereo. All steering wheel controls and radio functions work properly. I have also verified that the "wake-up" wire at the amp is getting voltage. I ran a jumper wire from the amp remote power wire at the back of the stereo to this wire at the amp harness. Still...only will the stereo work intermittently. The MOST converter has flashing red lights. The other side of the plug also has flashing red lights. I have verified 12+ power/acc. switched and ground at all of the power plugs. I have verified continuity between the MOST converter harness and the RCA plugs. Does anyone have any HELPFUL suggestions?! Should any wake-up/turn on functions need to be hooked up to anything on the CANBUS? Can I run a set of fiber optic cables from the MOST converter directly to the amp? This would bypass the rest of the loop that I really have zero use for...that I am aware of at least. I a;ready hooked up a bypass loop to the cd changer with no change in results. If a direct line to the amp is not feasible, how many...and where...are the additional bypass loop locations? Or should I just buy another converter box off of Amazon so I can return it easily if need be? I am on box 2 as it is.
Senior Member
Joined: Nov 2021
Posts: 473
Likes: 120
From: North West England
SL500
At the same time an optical "wake-up" takes place for 2 seconds.
This optical wakeup needs a reply for the MOST ring to lock.
What is possible is the MOST converter you have is not fully booted up when these wakeup signals are sent, so it sends no confirmation back.
When I install my new head units I leave all the other components in the ring (so I can go back to original).
I would suggest as an experiment is to leave the most converter powered by permanent supply, and see if this clears the issue, which will prove it is a timing issue on the MOST ring.
You may have success by changing the coding for MOST to match removed components, but not the Audio gateway or COMAND
