PC4 - Check Spout Circuit For Short to VREF, Ground and PIP

- Key "OFF".

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

- Ignition Control Module (ICM) disconnected.

For Shorts To Ground:

- Measure resistance between test pin 36 and test pins 16, 20, 40, 46 and 60 at the breakout box.

NOTE: During this check, when the 4-wire Heated Oxygen Sensor (HO2S) is connected to the vehicle harness on Electronic Ignition (EI) vehicles, a short to SIG RTN (Pin 46) may be indicated in conjunction with an actual PWR GND short.


For Shorts To VREF:

- Measure resistance between test pin 36 and test pin 26 at the breakout box.

For Shorts To Profile Ignition Pickup (PIP) circuit:

- Measure resistance between test pin 36 and test pin 56 at the breakout box.

- Is each resistance greater than 10,000 ohms?

Yes -- Reconnect all components. Go to Ignition Systems.

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