Hello folks, if I solve this myself I'll post the solution but it's got me stumped atm.

If I indicate left, the dash displays an error message about a bulb being out or something along those lines, and the indicator noise is rapid.

So I put the hazards on, and walk around the car - none of the passenger sides indicators are working at all - not the front (headlight), rear or side repeater.  The drivers side is all working perfectly.

I believe the indicators share a single fuse for both left and right sides of the car, so I didn't check that.

The sidelights, headlights, main beam, rear lights, brake lights and reverse are all working on both sides of the car, so I assume not an Earth issue.

What else can I check?

 

I took the headlight unit off the car and within it I found 3 thin wires coming from the plug connector but that lead to nowhere, which was a bit odd. There didn't seem to be anywhere they belonged, and the indicators were working fine the previous time i drove the car.  The only 'change' between me driving it when everything worked fine and now, is it rained a LOT, and I found someone had tried to pry out presumably to steal my smoked side repeaters but seemingly they had given up or were disturbed because they were still on the car and I just popped them back in.

Possibly a short-circuit on the passenger side indicator circuit. They are controlled by the GEM which will have turned off the power to that side until the fault is cleared.

I'd remove your passenger repeater indicator and check the wiring to see if it's been damaged. Also remove the bulb from the repeater and check to see if the indicators work.

Just change the bulbs and clean the contacts and as @unofix says, ensure side repeater is also working

A blown bulb can sometimes surge the remaining bulbs on the circuit and blow them, especially if they're old and on the way out anyway

5 hours ago, DaveT70 said:

Just change the bulbs and clean

You know that we're both mugs 🤣

Thanks chaps, much appreciated, I will give it a go and report back :)

SOLVED: It turns out when I said earlier that someone had tried to steal my smoked side repeaters, well I guess they thought they could disable the alarm by shorting the bulb connector wiring - I found the passenger side insulation was all burned and pulled off the wires and then the positive/earth wires twisted around and around each other.  I straightened it all out, added some insulation tape as a temporary measure, and the front and rear indicators are back in action. I need to source a new bulb for the side repeater.

 

Thanks again for the suggestions all!