Intermittent Electrics

My daughter has a '98 Polo, 1.6 auto. The ignition switch broke 12 months ago and was replaced. Recently various intermittent electrical faults appear - - intermittent wipers, indicators, door and hatch won't unlock, intermittent indicator lights on the dash for handbrake on or ABS. Worst of all, occasionally when trying to put gear lever into Park position a terrible graunching noise like trying to change gear without the clutch.

I presume that the gear selection and declutching process in an auto uses solenoids.

Seems to me that all these intermittent electrical problems might be related, and possibly related to the wiring around the ignition switch.

All suggestions on what the problem might be, - - or how to track it down, are welcome.

An Update

The problem is still not solved. Service Centre replaced Relay 30, but the problem still remains. The symptoms are now a little clearer - -

Intermittently while driving the ABS light coms on, the Handbrake light comes on, and at that time the indicators and wipers [and maybe the lights] do not work. If the problem is still there when the car is stopped, then when trying to move the gear shift into Park the starter motor is engaged [terrible graunching sound].

The Service Centre won't let me look at the wiring diagrams. I'm an electrical engineer and with these symptoms sometimes a bit of logical thought can find the likely cause. But no - - they rely almost exclusively on teh diagnostic codes.

Any help appreciated.