No oil pressure warning light

[RonN]

Thanks to everyone who offered suggestions for a wiring diagram, the closest I got was an Omalley one online.

However, this is still not very accurate, so I am still unable to trace another electrical problem I have with my 1979 -1500 spitfire. The brake warning light comes on with the ignition, but the oil pressure warning light does not illuminate. I have disconnected the pressure switch and put the wiring directly to earth, I have changed the bulb but neither has cured the problem. The wiring is White centre and Black/Purple outside on the warning light and  Brown/White centre with 2 Black/Purples to the outside on the oil light. I can get continuity on all of these wires but if I remove the bulb in the oil light the brake warning light goes out. I guess these lights are interconnected but I do not know how.

Should there be a special bulb in the oil light, there seems to be an unusual one in the brake warning light or could the PDWA switch be causing these problems I do know how that works or how to test it.

Any electrical guru's out there with the answers please.

 

Thanks

 

[yorkshire_spam]

Have you got an electrical meter?

If you have, the white wire at the warning lamp should go live (about +12v) with ignition in the "run" position. 

 

[RobPearce]

This may not be an electrical problem at all. I had a non-functional main beam repeater on my first Vitesse which turned out to be due to the rubber sleeve behind the jewel having shrunk and closed over. The fact that removing the oil light bulb changes things means that bulb is intact and the wiring to it is okay.