Test Description
WARNING: This page is about a different variant/trim than selected.
The numbers below refer to the step numbers on the diagnostic table.
- 2: When the system is operating correctly, the HO2S 1 voltage should toggle above and below the bias voltage. You may need to operate the vehicle within the Freeze Frame conditions and Conditions for Setting the DTC in order to duplicate the malfunction that was detected by the ECM.
- 4: The specified value is what is measured on a correctly operating system.
DTC P1171
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views |
||||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | - | Go to Step 2 | Go to Diagnostic System Check - Vehicle |
| 2 |
|
300 mV | Go to Step 4 | Go to Step 3 |
| 3 |
|
- | Go to Step 4 | Go to Diagnostic Aids |
| 4 |
|
350-550 mV | Go to Step 6 | Go to Step 5 |
| 5 | Test the HO2S 1 high signal circuit for a short to ground or a short to the HO2S 1 low signal circuit. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
- | Go to Step 11 | Go to Step 8 |
| 6 |
|
- | Go to Step 11 | Go to Step 7 |
| 7 | Inspect for poor connections at the harness connector of the HO2S 1 sensor. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
- | Go to Step 11 | Go to Step 9 |
| 8 | Inspect for poor connections at the harness connector of the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
- | Go to Step 11 | Go to Step 10 |
| 9 |
IMPORTANT:
Before replacing the HO2S, determine and remove any source of contamination. Replace the HO2S 1. Refer to Heated Oxygen Sensor Replacement - Position 1
.Did you complete the replacement? |
- | Go to Step 11 | - |
| 10 | Replace the ECM. Refer to Control Module References
for Replacement, Setup, and Programming. Did you complete the repair? |
- | Go to Step 11 | - |
| 11 |
|
- | Go to Step 2 | Go to Step 12 |
| 12 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? |
- | Go to Diagnostic Trouble Code (DTC) List - Vehicle | System OK |