LS1Nova71 need help! Schematic help please...
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LS1Nova71 need help! Schematic help please... I am working on a 2002 Duramax that I put a '69 Chevy truck over. I am trying to get the cruise working and am having trouble. I am getting power through the on/off switch on the gray and the lt. blue is hooked to the closed side of the brake switch which are standard bulbs to show it load, no LED's or anything fancy. I am confused on what signal the set and resume momentary buttons should give the ecm. The switch lever I have is an aftermarket switch that is giving both the set and resume 12 volts when pressed. I know the ecm needs to see either continuity or not through these momentary buttons, but am just not familiar enough with reading the schematics to know exactly which the ecm wants to see. To me it looks like they both provide 12+ when pushed, but I hooked them up and it's not working. What am I missing here? Thank you so much
Last edited by AaronOregon; Mar 30, 2018 at 12:41 AM.
You are correct, the PCM is looking for momentary 12v on those wires. What switch are you using? Because most aftermarket switches supply 12v the whole time the switch is set to "on" and momentarily remove it when pushed. This could be your problem.
Thread Starter
Teching In
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It's the Rostra 250-3020, but I have the little harness they sell that reverses the momentaries to 12v when pushed. Bench tested it before install and it's working as advertised. What's weird is when I bench tested it I would get 12.3v out of the momentary switches on the volt meter, but they would not light my test light. The on/off switch would though. That had me a little baffled as to why.
Last edited by AaronOregon; Mar 30, 2018 at 09:32 AM.
I don't know why the test light wouldn't light if you're getting 12v on your voltmeter, unless you didn't have it grounded good or something. Anyway, do you have both brake switch wires hooked up? C2 59 purple wire at the ECM needs power with the brakes NOT applied and C2 18 light blue needs power WITH the brakes applied.
