DS2 - Check Continuity of the Harness Circuit

- Key "OFF".

- Breakout box installed, Powertrain Control Module (PCM) disconnected.

- Disconnect Programmable Speedometer/Odometer Module (PSOM).

- Measure resistance between test pin 3 at the breakout box and PSOM(+) circuit at the PSOM vehicle harness connector.

- Measure resistance between test pin 6 at the breakout box and PSOM(-) circuit at the PSOM vehicle harness connector and chassis ground.

- Is each resistance less than 5.0 ohms?

Yes -- Go to DS3. DS3 - Check Harness Circuit For Shorts to Power and Ground

No -- Service open circuit. Remove breakout box. Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)