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-   -   non working highline (https://www.the75andztclub.co.uk/forum/showthread.php?t=320291)

Martin Butler 30th July 2022 08:24

non working highline
 
Hi, can anyone help, I have an non working highline system, its completely dead, i've checked fuses, and i'm getting power, nothings blown, but the system is dead, no sat nav light, even the tv unit is dead, i fitted a spare radio amplifier, the BM24 type, and still nothing, before the sat nav would work, and everything but the radio, that's why i got a replacement unit, there is a live reading at the multi plug, so powers reaching the boot mounted radio unit, is it possible for both the original, and the BM24 to be faulty, i could send the BM 24 off to be checked, its £50 just for that, and could be a lot more if parts are needed, is there a way to rig up a test unit for these radios

SD1too 30th July 2022 10:20

Hi Martin,

I doubt that the radio unit is the problem.

First of all, when you first unlock the car does the navigation computer/disc drive switch on and display a red LED beside the CD slot?

If you wait for about 30 seconds to a minute without touching anything on the car, does the LED extinguish?

Is the LCD screen in the centre console completely black at all times?

When you refit the original radio unit, does everything work except the radio as before you tried the BM24?

Simon

Martin Butler 30th July 2022 10:48

the lcd screen is completely black at all times, nothing comes on, no red led at sat nav, when i tried swapping over back to the original unit, no nothing works, as i posted, before at least some stuff powered up, but now everything is dead, yet i've checked the fuse box, no fuses are blown, and there's a live feed at the multi plug does the other units rely on power from the radio tuner?

SD1too 30th July 2022 11:32

Quote:

Originally Posted by Martin Butler (Post 2940913)
... does the other units rely on power from the radio tuner?

No they don't. All units receive a parallel power supply from both battery and ignition switch aux. feeds.

What all the units have in common (including the rotary coupler for the steering wheel controls) is a K-bus connection and I suspect that's where the problem lies. Earlier this year I looked at a member's tourer with the same symptoms as yours. Her K-bus was reading incorrectly at the radio unit but we were unable to trace the source of the problem in the time available since the header C0295 wasn't located where RAVE said it should be. :o

Simon

Martin Butler 31st July 2022 10:17

Where are the K BUS connections? and is it just a case of testing for a live connection, at source, then tracing it back to each unit, I understand there is a soldered multi joint by the drivers seat, that can be problematic, before everything worked fine, except for the radio, I fitted an android unit which worked fine, and left everything else unplugged because it was draining the battery, and when i got the BM24, I put the original equipment plus the BM24 back in the car, and since then, everything is dead, sat nav, tuner, and tv box.

SD1too 31st July 2022 15:52

Quote:

Originally Posted by Martin Butler (Post 2940999)
Where are the K BUS connections? and is it just a case of testing for a live connection, at source, then tracing it back to each unit ...

Each unit will have the K-bus on one of its connector pins. The wire colour code is white/red/yellow. You'll need a multimeter to check that the signal is there but it's not a straightforward "live" +12v. The aim is to discover which unit is responsible for a K-bus fault. As I said in my last post, there is a "header" which distributes the K-bus separately to all the high-line units but I was unable to find it on another member's tourer without dismantling a lot of the fascia. It wasn't behind the LCD screen where RAVE says it is.

You may need the help of T4 and an operator who is willing to spend time going through a logical fault-finding sequence to locate the faulty unit.

Simon


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