Pin Voltage Tests
CAUTION:
Use care while performing voltage tests. Shorting a positive probe between a connector terminal and ground could damage wiring harness, component, ECM/PCM or all three.
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 GENERAL INFORMATION before disconnecting battery. Before disconnecting battery, obtain anti-theft code for radio. After battery is reconnected, CODE will appear on radio display. Enter anti-theft code using select buttons and radio will begin working. If code is entered wrong 3 times, leave radio on at least one hour and enter code correctly. Any time radio power is lost, pre-selected radio stations will have to be set. For more information, see owners manual.
NOTE:
Unless stated otherwise in testing procedures, perform all voltage tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance. DO NOT disconnect ECM/PCM connector to perform voltage test unless instructed to do so. ECM/PCM may be removed to make it easier to access connector. Carefully backprobe ECM/PCM harness connector to avoid connector damage. Voltage readings may vary slightly due to battery condition or charging rate.
Pin voltage charts are supplied to reduce diagnostic time. Checking pin voltages at the ECM/PCM connector determines whether ECM/PCM is receiving and transmitting proper voltage signals. Diagnostic charts may also help determine if ECM/PCM harness is shorted or open. See appropriate illustration. See Fig 1 -Fig 29 . Perform repairs and/or component replacement as necessary. Recheck pin voltage to confirm repair.