C5 Multifunction Display - Buttons on Radio not Functioning

seroyen · Post by **seroyen** » 02 Jan 2011, 03:47

Hello all, can anyone help me on this? Model is 2005 C5 2.0i 16V (Petrol).

Recently, all buttons (Menu, trip computer etc.) on the stock Blaupunkt RD4 radio which control the multifunction display have stopped working. I have no problems turning on the radio using the on/off switch and that is the only button working. I'm also unable to eject the CD using the eject button.

Stalk controls at the steering wheel are still working fine for trip computer and radio controls.

Have run Lexia diagnostics and confirmed that the multifunction screen is not receiving any button commands from the panel.

Should I replace the RD4 unit or is there another kind of communication board involved? Any help would be greatly appreciated!

Trainman · Post by **Trainman** » 02 Jan 2011, 08:55

Try pressing and holding the 'DARK' button down, this should reboot the unit. Hopefully that will solve it.

seroyen · Post by **seroyen** » 03 Jan 2011, 09:00

Thank you Trainman for the suggestion.

I've tried pressing and holding the 'DARK' button in excess of 15 seconds and the unit did not seem to respond, in both cases when the radio was on or off.

Does this clearly indicate a problem with the radio unit or is the multifunction display and communication board involved (if there is any)?

I've also run the radio panel illumination and it's working fine.

Citroenmad · Post by **Citroenmad** » 03 Jan 2011, 09:07

Have you tried taking off the battery and then reconnecting it? This should reset things if its just an electrical glitch its picked up.

Otherwise i would be thinking radio, though ive not heard of this problem before.

Trainman · Post by **Trainman** » 03 Jan 2011, 09:40

I'm thinking that if the controls on the steering wheel are working, then it could just be problem with the head unit.

At the time the buttons stopped working, had anything happened? were you working on anything else? Perhaps one of the buttons is stuck in slightly and is stopping the others from functioning..............

seroyen · Post by **seroyen** » 02 Feb 2011, 05:48

Thanks for all the suggestions. It was indeed the problem with the head unit. I have used a multimeter on every single button contact in the front panel and found one of them to be shorted. Traced back to a point where, very weirdly, I found two separate circuit lines to be connected although not seen physically. Drilled a hole through and manually used thin wires to reconnect the lines again and all's fine now.

Thanks again!