XB173 - Check Data (+) and Data (-) Circuit Continuity

- Key "OFF".

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

- Variable Control Relay Module (VCRM) disconnected.

- Measure continuity between test pin 18 at the breakout box and Pin 21 at the VCRM vehicle harness connector.

- Measure continuity between test pin 19 at the breakout box and Pin 23 at the VCRM vehicle harness connector.

- Are both resistances less than 5.0 ohms?

Yes -- Go to XB174. XB174 - Check DCL In VCRM

No -- Service open in DATA (+) or DATA (-) circuit. Remove breakout box. Reconnect all components. Start engine. Turn A/C "ON", wait 15 seconds. A/C "OFF". Engine "OFF". Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)