X116 - Check Left Front HO2S Circuit For Short to Power

NOTE: Due to the Internal circuitry of the Powertrain Control Module (PCM), an intermittent left/front Heated Oxygen Sensor (HO2S) signal short to power could produce a Continuous Memory Diagnostic Trouble Code (DTC) 542 or 524/543.

- Key "OFF".

- Install breakout box, if applicable.

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

- Connect a test lamp between the left/front HO2S test pin and test pin 40 at the breakout box (refer to Pinpoint Test H for appropriate HO2S test pin). H - Test Schematic

- Key "ON", engine "OFF".

- Observe test lamp for an indication of a fault while performing the following (the light will turn on bright when a fault is detected):

- Shake, wiggle, bend the left/front HO2S circuit from the HO2S sensor to the PCM.

- Lightly tap the HO2S sensor (to simulate road shock).

- Is fault indicated?

Yes -- Isolate fault and service as necessary. Remove breakout box. Reconnect PCM. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- For further diagnosis using an EEC-IV monitor box or Scan Tool, go to Normal Scan Data Values. If an EEC-IV monitor box or Scan Tool is not available, go to X120. X120 - Road Test