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Triumph TR6 - Oil Pressure Switch Wiring

Hi all, got to take the 73 TR6 out yesterday. It was nice and warm and I had a blast driving thru the mountains here in NY. Later that day I decided to finally replace that old canister oil filter with a spin on. All I had to do to get the canister out and the adapter in was to unbolt the clutch slave cylinder. Of course something else went wrong while doing this. It appears that the 2 out of the 3 wires connected to the oil pressure switch were put on bad and the wires pulled out of the connector. Can anyone tell me the correct wire color connections. I have the 3 plug connector on my year.

O Top
Left 0
O Bottom

Thanks in advance.

Top black ground.
left white/brown to low pressure lamp.
bottom white/purple to anti run on valve.

Thanks to Dan Master's TR wiring diagrams about halfway down this page. Pick out yours and print.
Bill Brayford

Ok thanks. I hooked up all three wires per the wiring diagram. However the green low oil pressure lamp on the tach gauge still doesn't light up. I verified that there is no wire break between the switch and the lamp. I am assuming that the green lamp should glow when the key is turned on just like the red ign lamp. Please correct me if I am wrong. I am going to explain how I think the circuit should work. If I am wrong someone please let me know. :-) It looks like the circuit gets it power from the voltmeter(whatever that is), from the voltmeter the power travels to the brake fail lamp and then connects to both the low oil pressure lamp(which connects to the oil pressure switch) and the brake failure switch. Now with the ign turned on but without the car running, both switches should be closed which would complete the circuit and both the low oil pressure lamp and the brake failure lamp should light. I should mention here that the brake failure lamp doesn't lite either. Well my understanding of the circuit is correct then I am going to say the power from the voltmeter is missing. I say this because I already hooked the oil pressure connection directly to ground and the lamp didn't lite. Can someone also tell me what the purpose of the voltmeter is and what it is. Thanks from a newbie.

PS: I will mention that the PO had installed a CD receiver and hacked up the wiring under the dash. There still are a few other circuits that don't work so you might be hearing from me again.

I'm assuming tour 73 is the same as my 75....Green won't glow when ign is on it is for the turn signals, is for high beams is for oil and red is for ignition and both will glow as the car starts till the oil pressure climbs and the voltage stabilizes both in a few seconds normally. The voltmeter basically monitors the alternator and informs you if it is idle with nothing on it will show 13 to 15 volts approx and lower if the fan and wipers etc are on.If it stays below 12 volts you can have a failed alt or battery
Charlie Ballard

Charlie, on my 73 the high beam lamp(blue) and the turn signal(green) are on the speedometer. The tach has the oil lamp(green) and ign lmap(red). Maybe someone changed the gauges during the life of the car. But thanks for responding.

Ok Folks, I've solved the problem. It seems that Triumph wired the oil pressure lamp in series with the brake warning lamp. The warning lamp was blown, hence no oil lamp. Everything is glowing wonderfully. Thanks to all.

That is exactly the correct wiring.
Go to the WEB site Bill mentions above for the schematics.
Rick C
Glad to hear u have a glow on:)
Rick Crawford

This thread was discussed between 05/04/2004 and 09/04/2004

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