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Lifeline rain light

EFI Wiring Fundamentals

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Not sure if anyone has worked with these but my buddies who's car I am helping with is looking to have a button on the steering wheel to activate the flashing light. It has a 3 wire set up . Two for power one ground. Once both wires have been given power it flashes. I have wired each wire into the PDM. What I want to know is, where do i put the wire to trigger the PDM to power both pins when the button is pressed? I assume a digital/switch input on the PDM and some programming but have never worked with Motec so am not sure. Thanks.

You're on the money. Wire one side of the steering wheel button to the PDM input, and the other to one of the 0V pins on the PDM. The you can program the PDM to activate the two outputs the rain light is wired to, when the button is pressed. You'll be able to use a momentary button for this, as you can set the PDM up in a 'latching' fashion, so that one press turns the rain light on, and another turns it off.

If you only ever want the light to flash, you could use just one output and wire it to both inputs of the rain light, but if you've got spare outputs on your PDM, wiring one to each of the rain light inputs will give you more flexibility down the line.

Thanks Zac, actually was thinking about it but could i wire it into an input on the M150 and have the message sent over CAN to tell the PDM to turn on both pins?

Yes, I'd say it'd absolutely be possible to do that. I setup a single seater this way, but it was a Life Racing dash on the steering wheel that read the button presses and sent them to the Pectel ECU via CAN, which ran the rain light.

It's a great way to set it up, as it decouples the operation of the rain light from the button, so you can make it work however you like in the future without having to modify the wiring harness :-).