Wiring Help

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03-16-2020, 07:55 PM

Matt Eckert

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Wiring Help

I have a 12v Cummins that is getting swapped into a 2001 truck. I am using the wiring harness from the 5.9 gas motor and am wondering what needs to be done to get the tachometer to work. Any suggestions?

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03-16-2020, 09:28 PM

MoparFanatic21

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Quote:

Originally Posted by Matt Eckert

The tach works off the crank sensor. Would have to tap into it

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03-17-2020, 01:24 AM

DerTruck

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To be more precise, the tach is driven by the PCM which in turn uses the crank position sensor (engine speed sensor on the front in case of diesel). You probably need a 98 PCM to drive the 2001 cluster properly.

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03-17-2020, 10:59 AM

Matt Eckert

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Would I need a PCM for a gas truck or diesel?

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03-17-2020, 11:00 AM

Matt Eckert

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I have found the signal wire on the sensor itself, would you happen to know what color wire would have sent a tach signal from the PCM of the gas motor?

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03-17-2020, 11:59 AM

HeyYou

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All that info runs on the communications bus. Essentially, the cluster is a display only. The PCM tells it what the various gauges should be reading. Even the friggin gas gauge.

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