HVAC center display, windows an seats not working with head lights off
 

Hi

Our X358 (2.7 diesel) hvac display flickers as you drive along, buttons around satnav dont illuminate, and the heated seats have stopped working. Also the windows won't work unless the headlights are on.

Any ideas what might be causing all of these to play up?

Is it a common earth for all?

Fuses look fine.

"Has the battery been checked recently?" is my number one response to all things electrical. Once the battery has been checked and cleared then the real hunt will begin.

It's had a new battery two weeks ago but that hasn't helped. When you say 'check' the battery do you mean terminals or voltage?

Spent this afternoon wiggling wires with no joy. Does anyone have a wiring diagram of know whats common between all these circuits?

Flickering display indicates an intermittent power supply. The Front End Module controls the front heated seats, but the modules all link together over the SCP (Standard Corporate Protocol) network. Driver Door module controls the windows and is again linked via the SCP.

The instrument and button lights intensity is varied by the rotating control. Check this does vary the intensity.

Other thing is, anything happened recently with the car. This was a question that we used to ask of a computer problem - anything new been installed recently ?

My JTIS CD has wiring diagrams, but I can't get it to work at the moment. It's quite unlike what I was once familiar with in cars !!

Nope nothing has been installed.

One other thing to add is that driving downhill the hvac display stops flickering, uphill it starts again.

Can anyone tell me where the earth points are?