Adding a sensor

[tf11311]

I?m fighting transmission anomalies and have source everything needed to add a 5v line pressure sensor to the test port of a 4L60 on a 2008 Tahoe with an E38 ECM and a T42 TCM. I?m stuck at the point where I?m trying to find a 5v keyed power source on the computer pinouts that isn?t being used for the existing harness. Basically I don?t want to splice into any wires in the existing harness for 5v power. I see there are several unused pins on both computers but it doesn?t say what they are ie. control, ground, 12v, 15v or return signal.

[LilSick]

https://www.amazon.com/Neiko-40508-D...DER&gQT=1&th=1

[abc]

If you know how to make a professional connection, there is no harm is pulling your 5v supply from an existing sensor/circuit. The current draw is so minimal you will not overload it by adding one additional load/sensor to the circuit.

[blindsquirrel]

All the 5v pins come from one of two 5v rails inside the E38. In the earlier PCMs there was only a single 5v rail for everything. Any one 5v pin is functionally identical to any other.

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