Rear Sidelight Problem

[Volksfolk]

Hi all,
I have a Mk5 Polo (2001). In the light cluster on the offside rear all bulbs bar one are working. The sidelight (5w) was replaced, I've checked the fuse under the dash and all seems good to go. I have read that it could be just a dirty connection, which I shall investigate. Has anyone got any further advice or suggestions?
Addendum.
I have replaced the bulb holder, but still the running/parking light refuses to work. All the others work fine!
Most annoying.
Looks like my Bank Holiday weekend is going to be spent tracing wires ...

[mswuk]

I think the parking light only works when you leave the indicator on.ie leave it on left turn and left rear light will stay on and vice versa.
Have you checked the bulb's connections?

[alexperkins]

As mswuk says. Try a multimeter on the bulb terminals

[Volksfolk]

After poking about with a circuit tester screwdriver and wiggling wires all day, I guess it's best to call an auto electrician ...

[alexperkins]

Where are you based?

[Volksfolk]

I'm up in Manchester. I'm not pressed for time to get it looked at, but it needs sorting before the nights draw in.
The indicator stalk contact may be involved as the other day I could hear it ticking, but the lights were not activated. Someone mentioned the parking lights are tied into this circuit for parking, but when I put the indicator on and turn off the ignition, the sidelight still does not illuminate.
Next on my to-do list is to replace the radio. It is "of it's time", but I want something that will play my digital music. Have to get a converter to link the old loom to iso connection. Cheap, but a bit of a faff.

[Volksfolk]

UPDATE.
I've just realised that the twisty light switch thingummybob can be pushed in and indeed pulled out (not sure it should do that lol), making the foglights come on.
So ..... do my lights come on on the duff side???? No.
So, maybe its the switch itself???
Seems easy to remove. Push in, twist to vertical and pull. http://youtu.be/5v-RKI5X5Zw
But how do I test if its the switch or the loom?

[alexperkins]

Does the offside front sidelight work?

[Volksfolk]

Yes

[Volksfolk]

Good News!
It turns out after all this faffing, it turned out to be a schoolboy error.
I had the correct size and wattage bulb in situ, but double filament. All I had to do was change the bulb to a single and Voila!

[alexperkins]

We like an easy fix