CD Changer goes off when I press the brake pedal!

[barry jones]

Hello all....

Having fitted the CD Changer and phone kit from a 2002 into my 2003 facelift S Class and getting it all to work.... I finally got round to trying it today for a proper go!

I need to buy the S Class phone microphone because although everything works, the microphone is an add on which mine hasn't got and I now need to order!

Anyway, previously I have sat in the car and tried the CD Changer and worked through the tracks with the steering wheel controls and everything has worked fine. I have never really used it on the road until today. I drove out and put the cd changer on and everything was fine until I braked and then the changer cut out.

Strange I thought so I tried it again and sure enough the changer works well until I touch the brake pedal and it all goes off and then comes up with "NO CD CHANGER" on the radio display and NO CDC on the dash.

Now obviously I have spliced into the wrong wire somewhere but all of the splicing was done in the passenger footwell as per factory fit. Once I turn off ignition, remove key and then restart; it all works perfectly well until I brake again.

I have a feeling that it may be the ground wire that is wrong as I have removed the blue/black and it still happens, I have removed the red/black under the rear seat and it still happens. The red/black under the front passenger side turns off all power completel to the CDC so it may be that one and I haven't touched the ground wire yet as I can't get at it and it is dark!

It could also be the wake circuit up on the fibre ring (d2b) as only the cd changer and phone are affected and althoough the radio goes silent for a short time if I press the brake, it does come back on unlike the CDC and phone.....

So if anyone has any ideas as to what colours the brake circuit uses (so I can check what I have connected to) that would be great. Otherwise I will have to remove everything again and I don't fancy that!

Thanks

Baz

 

[television]

The D2B wake up uses the CAN BUS., the brake lamp switch uses the CAN BUS as does the wake up and all of the CAN wires are in the foot wells

Did you join the CD player into the CAN when you installed it

 

[television]

Just coming back to this as a point of interest to me. My Comand does not go to sleep, on many cars the OCP is the fault or the battery converter, on mine it is the Comand head unit, for when they are not sleeping the CD changer clicks away until the battery gets too low, and shuts it down.

The Can bus wires for the head unit are in the kick panels in the front,and run along the sills to the rear, so I will put in my own wake up.

This is why I think that your fault is a CAN one

 

[barry jones]

The D2B wake up uses the CAN BUS., the brake lamp switch uses the CAN BUS as does the wake up and all of the CAN wires are in the foot wells

Did you join the CD player into the CAN when you installed it

There was already a plug behind the panel in the boot which I assume was the wake up. the only wires I have connected appear to be +ve and -ve wires for the phone ad CD changer. Under the floor there is a CAN connector block with countless plugs all in place. The CD obviously is using the CAN to wake up until I press the brake pedal which then seems to knock it out again!


I have already programmed in the changer and phone using a star unit and in the diagnostics on the radio; if I don't press the pedal, everything shows up on the D2B ring, when I do, only the headunit shows up....


Any other ideas greatfully accepted!

Baz

 

[television]

I think Barry the the CD changer is plugged into the wrong CAN connector on one of the X connectors

 

[barry jones]

How would I check that malcolm? Under the floor in the passenger side was a strip with about 10 twisted brown, brown/red cables all plugged in.

The plug I used was taped up behind where the CD Changer fits in the boot so I am guessing it must be the right one.

Could it be that the earth connection has been put on the wrong place? and is shorting something on pressing the brake pedal? I know on the older cars, the brake pedal makes and brakes a -ve connection rather than a +ve one?

What I may do is try taking the phone components out of the d2b ring first although the 6210 phone all works well with contacts uploaded etc. until I press the brake pedal!

and what is an "X connector"
Thanks again

baz

 

[television]

I was not correct in that post Barry, only the head unit connects to the CAN and this controls all component in the D2B ring, the correct point for the Comand head unit is normally in the front foot well. If you disconnect any point in the D2B ring it all shuts down, apart from the head unit. If for instance I removed the power from my TV, the message would come up "no TV"

I do not think that there is a ground lead problem as the things are all bolted down to the chassis earth.

We know that there is nothing wrong with your brake light switch, for when they go, they kill the CAN bus.

Could it be where the Comand CAN connector is plugged in,you have quite a few different points.

I will try and read the retro fit on your car when I get a minute