Intermittent steering signal lamp problem

[sagaboy]

I am facing an intermittent steering stalk signal contact problem 50% of the time, only the left signal is not working--nothing at all when the steering signal stalk are push down for the left signal. I have sprayed contact cleaner on the steering signal stalk but have no effect. BUT the emergency lamps are all working, no problem at all.

Any suggestions on where I should start looking for the problem?

[perrib]

Typical old VW switch. Just to be sure monitor the output with a test light just in case it is not the switch.

[Marc]

Could also be a soldered connection in the switch has broken. Left is the black wire with white stripe.

[sagaboy]

Good suggestions. Thanks a lot )
Will monitor the output with a test light
AND
check the soldered connection in the switch--in my case the LEFT is black with green stripe.

[Marc]

...in my case the LEFT is black with green stripe.

That'd be the first VW t'signal switch I've ever encountered which is wired that way, but I suppose it shouldn't surprise me that it'd be yours

[sagaboy]

Found the cause of the problem of intermittent signal lamp working off and on. The signal lamp wires from the steering wheel wire harness are connected to a pretty large original plastic casing wire crimp joint connectors for the front and rear signal lamp. One of the crimped connector was loose inside the plastic joint casing hence causing the intermittent signalling problem.