Series III lightweight. Gauges, lights and others...

assuming it is like my 101, could be the brake test button. Tests the fail valve that connects the 2 brake circuits (somehow!)

could be for IR headlights. Removed before it left the army and now fitted to make your headlamps dimmer and more likely to break ;)

Trying to remember back to my Lightweight days, the switch under the protective flap IS for the IR headlights (when fitted in place of the tungsten ones). I think it may also cut the circuit to all the other things that emit light, such as brake and indicator lights (although that COULD be the multi-position lighting switch in one of its 'Convoy' positions). The idea is that in IR mode (when you're moving 'blacked out') no other lights can come on accidentally and give your position away.

This is why the military wiring looms are so different to the civilian ones. I do have somewhere out in the workshop a rather tatty copy of the wiring diagram which I could scan and email if required... might take a few days to find a time slot, though.

Yes, the circular red button that sits almost flush with the fascia is (IIRC) the brake warning light and its test facility -- comes on if the two brake circuits get unbalanced. It's controlled by a shuttle valve on the top of the front chassis rail roughly below the bulkhead steering box. If both circuits are equal, the shuttle stays in the middle, but if one circuit goes down, the shuttle moves sideways and switches the light on. Makes brake bleeding an absolute s*d, particularly as you then have the devil's own job to get the shuttle back in the centre again. Amazing how often the wiring mysterious disconnects at this point to turn the blessed warning light off!

GRAEME ALDOUS Yorkshire

Hazard switch? when you push it does it pop out? Mine does and is.

Switch to test something, mine has all the wires cut so not sure what it does test.

Red middle is ignition light Left is green indicatotr Right is amber light that comes on to show the indicators are working when you have a trailer attached

Turns the instrument lights off so you can drive in with no interior lights on.

At least thats wht mine do.

I've posted scans of my old Lightweight diagrams on my pages.

There's the whole wiring diagram (720K) at

-- a but scratty I'm afraid, but the sheet had been well-thumbed in the workshop.

There's also my own (hand-drawn) interpretation (321K) of how the Infra Red switching system affects the rest of the lights etc on the vehicle at

Hope it makes sense to everyone.

GRAEME ALDOUS, Yorkshire