1983 KZ1100-oil light stays on

Hello,
Im thinking of buying a kz1100, ive always wanted one and i think i found a good deal. The seller says the oil light is always on. IS this a red light ,or could this be a not so bad repair?

I'd check the wiring before buying a new switch. Look under the #1 and #2 carbs(as you sit on the seat, it's left to right)and see if there is a wire going to the sensor, the connection may be dirty or loose.The wire may be BLUE with a RED stripe.

I believe the wiring is routed behind the sprocket cover with the side stand switch,the alternator output wires, and the neutral switch wire.

Having too much chain lube gets the sprocket cover real grungey inside and may affect those electrical circuits.

I forgot to mention, on these older Kawasaki 900's,1000's and 1100's, the engine has a roller bearing crankshaft needing very low oil pressure(usually 2.2 to 3.0 PSI)