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Pin Voltage Charts: Introduction

PIN VOLTAGE CHARTS are supplied (where available) to speed up the diagnostic process. By checking pin voltages at the electronic control unit, it is possible to determine if the control unit is receiving and transmitting proper voltage signals. Charts may also help determine if control unit harness has shorts or opens.

NOTE: When testing pin voltages, it is recommended that a DVOM with high input impedance be used in order to ensure accurate voltage readings.
Fig 1: Tracker ECM Terminal Pin Voltages
G121732Courtesy of GENERAL MOTORS CORP.