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Discussion Starter #1
Hi ~~~

My oil pressure light on the dash will not light red before starting the engine. The bulb checks okay (even put a new bulb in,) the wires from the first connector to the bulb test okay - but there is no voltage to that connector or to the bulb.

The manual says in two places to "check the function of the oil pressure switch" but does not say HOW.

The connector to the switch on the motor is a 2-wire connector.

When the engine is off, do these two wires supply 12 volts to the light or do they complete a circuit or do they complete a ground, or WHAT?

I get a zero-ohm reading between the two, between each one and the ground and I get no voltage from either when the ignition is on.

Any info is appreciated - THANKS!
 

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I don't remember the wire colors for the oil pressure sender but to test the gauge or light one of the wires needs to be grounded to the frame with a jumper. The gauge would do a sweep and the light would come on if working correctly.
 

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Poser Member # 99
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You could probally check continuity across the switch with a test meter . motor not running should be closed.
When motor is running open to shut light off or vise verse.
If you dont have a good case ground to the motor it won''t work. If you dont have power to the curcuit it won't work . Testing Can be done with a 12v test light commming off postive of battery terminal and checking across the switch to ground of motor. To see if switch is working . checking for power at the plug to ground will tell you if you have power going to the switch



Check all fusing you might have something blown some where
 

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You need to have voltage to the light first. The circuit then goes to ground through the op switch.Sounds like no voltage to the light.
 

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Discussion Starter #5
OKAY, problem solved - it WAS the switch/sender.

On this model the switch (for the oil lamp) AND the sender (for the oil gauge) are both in the small cylindrical unit that screws into the front/right of the motor.

Obviously (since a replacement part fixed it) it is possible for HALF the switch to burn out - in this case the SWITCH was fried but the SENDER still worked the gauge properly.

I never could figure out how to TEST the damn thing but today I was at the stealership and bought one to try ($30.)

I got home and didn't even have to install the unit, simply plug it into the bike's leads/plug (that was plugged into the old/installed switch) then ground the thing (a wire clamped from the switch's threaded install pipe to the bike's ground) and turn the ignition on. And the oil lamp lit up as it should.

The switch doesn't need to be installed since you are checking for absence of oil pressure, it simply has to be grounded into THINKING it is installed.

Of course without pressure it will not make the gauge show movement but that part was working anyway.

Just another lesson - thanks again for the replies.
 
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