Oil light
a short to ground on the signal wire
short to ground in the instrumentation
oil pump not circulating or worn and pressure not high enough
bad pressure sensor
restricted line or tank outlet.
Or does it not light up when you turn ignition on? if this, then try swopping the bulb with a new one or a known worker.
If still no light then you have a faulty switch/ wiring problem. Start at the fuses and trace towards the switch/bulb for a bad connection etc.
#1 suspect like mr. harley said would be the bulb. easy enough to check. you need to remove the cluster bar but taking out the two socket head bolts, flip the cluster over and remove backing and bulb. i replaced all of mine with led bulbs, they are bayonet base, i believe t2 size and i used daylight color tone to see in bright light.
if the bulb is good, under the machine on the filter boss, there is a switch threaded in, just jumper the wire to ground, light should come on, if not, trace power from light to source.







