996 c4s electrical issues

[helmutlaang]

Hi all
Not long owned my 996 c4s and have noticed a few strange electrical glitches.
First time I drove it in the dark the back light for the oil pressure gague went out around halfway through a 30 mile journey.
Also noticed the backlight on the tuner knob on the radio was flickering.

Fast forward a few days and noticed there is a high pitch noise,like a dry bearing or a tensioner,coming from the engine bay.This goes after being on tickover for around 30 seconds.

Then on Sunday night the alarm keeps going off.Car is in the garage and has been locked for several hours.After a few resets and alarms I leave it unlocked for the night.
Monday night was the same.Locked for 4 hours and the alarm sounds.
Tuesday travelling home I notice the O/S headlight is out.I think a blown bulb.Get home,stick it in the garage,turn engine off and ignition back on to check headlight and its working again,and was fine this morning.
I locked the car last night and disabled the IR sensors and the alarm was silent.

After doing some research it has been mentioned that a faulty ignition switch may be to blame.Even on PCGB buyers guide it mentions these are fairly common and will throw up strange electrical issues.

Another may be an earthing strap at the rear of the car.

Any other thoughts? reason I ask is because Im working 12hr shifts at the moment and commute for work so trying to narrow down what it could be.

Thanks

[Whitean3]

Faulty ignition switch sounds about right from what I've read too. I'm assuming your battery is in good condition? Could also be worth a check.