Hello, whenever my '74 is switched to the on position, whether running or not, the oil pressure idiot light blinks on and off with the directional relay...it does this regardless of whether the wire is connected to the sender on the engine, so i know the bulb is grounding out where it shouldn't....

here are some pictures. The black wire with green and whitish stripe goes from the idiot light to the directional relay, and there are two brown wires which I assume are grounds....is this correct? I don't see the idiot light wiring going through the flasher relay on the PP electrical diagrams...

Any ideas would be great!

i'd be surprised ...

looks like someone mixed up some wires ...

i only have the wiring diagram for an early car in front of me, so here it goes:

oil pressure sender -> green/red wire to pin 1 on the rear connector on the relay board -> to pin 5 on the front connector on the relay board -> straight to the bulb in the gauge

the bulb get's 12V from a red/white wire. ground is provided by the sending unit.

Andy

PS: as always, make SURE you got good ground for the gauge housing and make SURE you get 12V all the way back at the sender and make SURE the sender works (provides ground when warm) ...