Diagnostic Aids

Purpose of this test is to verify Powertrain Control Module (PCM) power-up during cranking. Lack of power at PCM during cranking can cause a no-start condition and a fault code loss.

1. Check VPWR PID  Connect New Generation Star (NGS) tester to Data Link Connector (DLC). Using scan tester, access VPWR PID from PID/DATA monitor menu. See procedures under ADDITIONAL SYSTEM FUNCTIONS in the TESTS W/CODES - 7.3L DIESEL article. Crank engine while monitoring PID reading. If PID reading indicates more than 7 volts, go to next step. If PID reading indicates 7 volts or less, check charging circuit, power and ground circuits. See CIRCUIT TEST A in the TESTS W/CODES - 7.3L DIESEL article.
2. Check RPM PID  Using scan tester, access RPM PID from PID/DATA monitor menu. Crank engine while monitoring PID reading. If PID reading indicates more than 100 RPM, go to next step. If PID reading indicates 100 RPM or less, check Camshaft Position (CMP) sensor circuit. See CIRCUIT TEST G in the TESTS W/CODES - 7.3L DIESEL article.
3. Check Fuel Pulse Width  Using scan tester, access FUEL PW PID from PID/DATA monitor menu. Crank engine while monitoring PID reading. If PID reading indicates 1-6 milliseconds, go to next step. If PID reading does not indicate 1-6 milliseconds, injectors are not receiving Fuel Delivery Command Signal (FDCS). For testing, see CIRCUIT TEST G in the TESTS W/CODES - 7.3L DIESEL article.
4. Check ICP PID  Using scan tester, access ICP PID from PID/DATA monitor menu. Crank engine while monitoring PID reading. If PID reading indicates 500 psi (3448 kPa) or more, go to GLOW PLUG SYSTEM OPERATION . If PID reading indicates less than 500 psi (3448 kPa), injectors are not being energized because of insufficient pressure. Perform INJECTION CONTROL PRESSURE TEST .