88TPI406GTA

The car is wired for a DFI 6 and has a custom harness on the inside. The DFI only uses the black 12 & 16 pin connectors (not the yellow 16 pin), so I am using a wiring diagram and a long test lead to confirm actual wiring of each actual pin to the individual sensor.

My actual question: Can the 5 volt reference signal be shared between different sensors or do they have to be separate?

Example, the TPS 5 volt reference signal and the MAP reference signal share the same pin on the DFI harness while the 730 wiring diagram shows that A5 should be the TPS 5 volt signal and A4 should be the MAP 5 volt signal.

The 2nd question is if these sensors can share the same ground? I assume so, but am sketchy on the 5 volt power for each sensor.

I think that the 5 volt signal coming from the ECM should be able to be shared as it assumes that each sensor has a full 5 volts, right? The ECM actually uses the incoming (input) signal from each sensor as data?

Any input would be welcome as I don't want to have to run extra 5 volt reference wires or ground wires if various sensors can share the same 5 volt power feed or ground.

Thanks!

Grumpy

It's best to wire things up, exactly as GM designed them to be. GM didn't run all the extra wiring without due consideration.

That said, the 5V pins at the ecm are tied together, inside the ecm. They do that to reduce the load on the cirecuit board traces. You can have ground loop problems by reducing the number of grounds, and where they connect to ground. Gotta be real careful, or you can have sensors that go *dead* during cranking, and odd stuff like that.

88TPI406GTA

Thanks for the response...it makes sense...

Now I am finished with the sensors, I have moved on to the IP connector and my questions with that

Thanks!