k-bus issues from flooded satnav

[Archie75]

so a few months ago i had a battery drain which i traced to the lowline sat nav unit in the boot being flooded. i removed this to let it dry out and it solved the problem. A couple days ago i went to plug the sat nav unit back in hoping it had dried out so i have it for pol, however it diddn't work and immediately after i had k-bus issues including the typical key fob not locking, "er" on climate control, no CD player, no indicators/ main beam indication lights.
so after some research i located the k-bus connector up behind the drivers kick panel and removed all connectors but 2,3 and 4 like instructed in this post https://www.the75andztclub.co.uk/for...=229444&page=2 but still no results.

my first question is, is this even the right k-bus connector for the sat nav unit? or is it located somewhere else?
https://photos.app.goo.gl/9vixA1bkntkSmSDX7

another thing i noticed was when removing the sat nav after the issues started, the top ground connection in the photo which goes to the sat nav in the boot was sparking.
https://photos.app.goo.gl/xYNoREkU5usTk4JP7

[SD1too]

Originally Posted by Archie75

... when removing the sat nav after the issues started, the top ground connection in the photo which goes to the sat nav in the boot was sparking.

Sparking suggests a poor connection and those nuts look horribly rusty. I would start by restoring those and the eyelet to bright metal.

Originally Posted by Archie75

... is this even the right k-bus connector for the sat nav unit? or is it located somewhere else?
https://photos.app.goo.gl/9vixA1bkntkSmSDX7

Yes it is but the K-bus connection to the navigation unit is shared with the Symphony head unit at that header.
If you unplug the navigation unit, is normal K-bus activity restored?

Simon

[Archie75]

Originally Posted by SD1too

Sparking suggests a poor connection and those nuts look horribly rusty. I would start by restoring those and the eyelet to bright metal.

Yes it is but the K-bus connection to the navigation unit is shared with the Symphony head unit at that header.
If you unplug the navigation unit, is normal K-bus activity restored?

Simon

Hi Simon. Thanks for the reply. Good to know it shares the connector with the symphony unit. No after I unplugged the sat nav the issue still persists. And unplugging the connector from the kbus doesn't fix the issues either.
Also turns out my poking around last night has left me without back lighting on my dials and buttons. Is this related to a connection on the kbus too?

[SD1too]

Originally Posted by Archie75

And unplugging the connector from the kbus doesn't fix the issues either.

Now that you've said that I have my doubts that you're looking at the correct header described in MGMarc's thread. That is basically a terminal block joining together wires from different sources. If it hasn't been interfered with, it should be bound in black insulating tape. It's not a connector so cannot be unplugged from another part.

Originally Posted by Archie75

No, after I unplugged the sat nav the issue still persists.

That seems to rule out the navigation unit itself then. Check those earth connections!

Originally Posted by Archie75

Also turns out my poking around last night has left me without back lighting on my dials and buttons. Is this related to a connection on the kbus too?

Information I've found on this states that it is a PWM signal (pulse width modulation) supplied by the LSM on a red/white wire. There is a K-bus connection to the instrument pack as well.

Are your main beam and direction indicator warning lamps working correctly?
Is the "door open" warning lamp working?

Simon

[Archie75]

Originally Posted by SD1too

Now that you've said that I have my doubts that you're looking at the correct header described in MGMarc's thread. That is basically a terminal block joining together wires from different sources. If it hasn't been interfered with, it should be bound in black insulating tape. It's not a connector so cannot be unplugged from another part.

That seems to rule out the navigation unit itself then. Check those earth connections!

Information I've found on this states that it is a PWM signal (pulse width modulation) supplied by the LSM on a red/white wire. There is a K-bus connection to the instrument pack as well.

Are your main beam and direction indicator warning lamps working correctly?
Is the "door open" warning lamp working?

Simon

Sorry completely new to working on my own car. I meant that I removed pin 8 from the k bus block after I had cut it free from the insulation tape and removed the outer plastic shell.
Earth connections now all shiny but still no results.
And no the main beam, indicator and door open lamps are not working.

So with the backlighting does that mean I've put the ipk and lsm wires back in the wrong places? Is there any way to find out which of the wires are which?

I also noticed in my kbus block that there is a wire with two ends that I'm guessing acts as a jumper between two pins. Do you know which positions they're supposed to be in?

[SD1too]

Further research has revealed that this header (C0289) is divided into two sections; one for K-bus connections and the other for panel and switch illumination.

Originally Posted by Archie75

... in my kbus block ... there is a wire with two ends that I'm guessing acts as a jumper between two pins. Do you know which positions they're supposed to be in?

It links 8 and 9.

Originally Posted by Archie75

So with the backlighting does that mean I've put the ipk and lsm wires back in the wrong places? Is there any way to find out which of the wires are which?

The K-bus connections on C0289 are in pins 1 to 10 as follows:
1 = Immobilisation ECU
2 = LSM
3 = Instrument pack
4 = BCU
5 = link to connector C0295 (more on this below)
6 = Sunroof ECU & rain sensor
7 = Parking distance control ECU
8 = link to 9
9 = link to 8
10 = Seat memory ECU

C0295 has a further six K-bus connections as follows:
15 = link from C0289
16 = CD auto changer
17 = Symphony radio/cassette unit
18 = Low line Navigation unit
19 = Not used on your car
20 = Not used on your car

By pursuing an error in RAVE I suspect that C0295 is a 20 pin rectangular blue header shown taped to C0289.

In theory it doesn't matter which WRY (K-bus) wires go where on C0289 so long as pins 8 & 9 are linked and they're only using pins 1 to 10.

Originally Posted by Archie75

... the main beam, indicator and door open lamps are not working.

Thanks for confirming. That shows that the K-bus is not working to the instrument pack or the BCU.

Regarding the loss of illumination on the instrument pack, this is fed on a RW wire from C0289 pin 15. Pins 11 to 14 should all have RW wires.

Confused?

Simon

[Archie75]

Originally Posted by SD1too

Further research has revealed that this header (C0289) is divided into two sections; one for K-bus connections and the other for panel and switch illumination.

It links 8 and 9.

The K-bus connections on C0289 are in pins 1 to 10 as follows:
1 = Immobilisation ECU
2 = LSM
3 = Instrument pack
4 = BCU
5 = link to connector C0295 (more on this below)
6 = Sunroof ECU & rain sensor
7 = Parking distance control ECU
8 = link to 9
9 = link to 8
10 = Seat memory ECU

C0295 has a further six K-bus connections as follows:
15 = link from C0289
16 = CD auto changer
17 = Symphony radio/cassette unit
18 = Low line Navigation unit
19 = Not used on your car
20 = Not used on your car

By pursuing an error in RAVE I suspect that C0295 is a 20 pin rectangular blue header shown taped to C0289.

In theory it doesn't matter which WRY (K-bus) wires go where on C0289 so long as pins 8 & 9 are linked and they're only using pins 1 to 10.


Thanks for confirming. That shows that the K-bus is not working to the instrument pack or the BCU.

Regarding the loss of illumination on the instrument pack, this is fed on a RW wire from C0289 pin 15. Pins 11 to 14 should all have RW wires.

Confused?

Simon

Very confused haha but that's extremely helpful thankyou. I will use all of that to give it another attempt. Hopefully will reply saying all is solved but will likely be more questions . Thanks for the help so far.

[Archie75]

RESULT!! thankyou so much for all your help Simon. Unplugging pin 18 from the blue header was the one. All functions functioning. (Apart from the satnav haha).

[SD1too]

Excellent, patience and persistence pays off!

Simon