Engine Controls - Pin Voltage Charts: Introduction
Pin voltage charts are supplied to speed up the diagnostic process. By checking pin voltages at the Electronic Control Assembly (ECA), 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:
Unless stated otherwise in test procedures, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance. Perform all resistance checks with battery power removed from the circuit unless stated otherwise.
CAUTION:
When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in the GENERAL INFORMATION Section before disconnecting battery.