Test TC-32A - O2 Sensor 1/1 Stays At Center
NOTE:
For connector terminal identification, see CONNECTOR IDENTIFICATION in SELF-DIAGNOSTICS section in this article. For wiring diagram, see WIRING DIAGRAMS - 2.7L
article.
- For O2 sensor/model identification see O2 SENSOR 1/1 IDENTIFICATION table. Start engine and allow it to reach operating temperature. Using scan tool, set engine speed to 1500 RPM. Using scan tool, read O2S 1/1 state. If O2S 1/1 state is switching, go to next step. If O2S 1/1 state is not switching, go to step 5).O2 SENSOR 1/1 IDENTIFICATION
Application Location Concorde & Intrepid Right Bank Upstream O2S - While monitoring scan tool display, wiggle O2S wiring harness. If O2S 1/1 state was locked at center at any time while wiggling wiring harness, repair wiring harness as necessary where wiggling caused problem to appear. Perform TEST VER-5A. If O2S 1/1 state was not locked at center at any time while wiggling wiring harness, go to next step.
- Condition to set trouble code is not present at this time. O2 SENSOR 1/1 STAYS AT CENTER DTC sets if upstream O2S signal voltage is .35-.55 volts for 1.5 minutes. Possible causes are: O2S output circuit open, O2S failure, PCM failure, dirt and/or moisture causing voltage tracking in connector, or faulty connections or wiring. Go to next step.
- Inspect all related wiring and connectors and repair as necessary. If no problems were found with wiring and connectors, test is complete. Perform TEST VER-5A. If related wiring and connectors were repaired, perform TEST VER-5A.
- Turn ignition on with engine off. Disconnect O2S 1/1 connector. Inspect wiring and connectors and repair as necessary. If no problems were found with wiring and connectors, go to next step. If wiring and connectors were repaired, perform TEST VER-5A.
- Using an ohmmeter, check resistance of O2S 1/1 sensor ground circuit between O2S 1/1 sensor connector (harness side) and ground. See O2S 1/1 CONNECTOR WIRE IDENTIFICATION (HARNESS SIDE) table. If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open O2S 1/1 sensor ground circuit. Perform TEST VER-5A.
- Connect a jumper wire between O2S 1/1 connector (harness side) signal circuit and battery voltage. See O2S 1/1 CONNECTOR WIRE IDENTIFICATION (HARNESS SIDE) table. Using scan tool, read O2S 1/1 voltage. If voltage is one volt or less, go to next step. If voltage is more than one volt, replace O2S 1/1. Perform TEST VER-5A.
- Turn ignition off. Disconnect Powertrain Control Module (PCM) connector. Disconnect jumper wire from O2S 1/1 connector. Using an ohmmeter, check resistance of O2S 1/1 sensor signal circuit between O2S 1/1 connector (harness side) and PCM terminal No. 30. See O2S 1/1 CONNECTOR WIRE IDENTIFICATION (HARNESS SIDE) table. If resistance is less than 5 ohms, replace PCM. Perform TEST VER-5A. If resistance is 5 ohms or more, repair open O2S 1/1 signal circuit. Perform TEST VER-5A.
O2S 1/1 CONNECTOR WIRE IDENTIFICATION (HARNESS SIDE)
| Application | Wire Color |
|---|---|
| O2S 1/1 Sensor Signal Circuit | Black/Dark Green |
| O2S 1/1 Sensor Ground Circuit | Black/Orange |
| O2S 1/1 ASD Relay Output Circuit | Orange/Dark Green |