Conditions for Clearing the MIL/DTC
WARNING: This page is about a different variant/trim than selected.
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.
DTC P0138 or P0158
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module Connector End Views |
||||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | - | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 |
|
1,000 mV | Go to Step 4 | Go to Step 3 |
| 3 |
|
- | Go to Step 4 | Go to Intermittent Conditions |
| 4 |
|
475 mV | Go to Step 5 | Go to Step 8 |
| 5 | Measure the voltage from the HO2S low signal circuit on the engine harness side connector to a good ground with a DMM. Refer to Circuit Testing
in Wiring Systems. Is the voltage less than the specified value? |
50 mV | Go to Step 6 | Go to Step 7 |
| 6 | Test the HO2S high signal circuit for a short to voltage or a short to the HO2S heater low control circuit. Refer to Circuit Testing
, Wiring Repairs
, and Heated Oxygen Sensor Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 13 | Go to Step 10 |
| 7 | Test the HO2S low signal circuit for a short to voltage. Refer to Circuit Testing
, Wiring Repairs
, and Heated Oxygen Sensor Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 13 | Go to Step 10 |
| 8 | The HO2S may be detecting a rich exhaust condition or may be contaminated. Inspect for one of the following conditions:
Repair any of the above or similar engine conditions, as necessary. Did you find and correct the condition? |
- | Go to Step 13 | Go to Step 9 |
| 9 | Test for poor connections and shorted terminals at the HO2S. Refer to Testing for Intermittent Conditions and Poor Connections
, Connector Repairs
, and Heated Oxygen Sensor Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 13 | Go to Step 11 |
| 10 | Inspect for poor connections and shorted terminals at the engine control module (ECM). Refer to Testing for Intermittent Conditions and Poor Connections
, and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 13 | Go to Step 12 |
| 11 | Replace the affected HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 2
or Heated Oxygen Sensor Replacement - Bank 2 Sensor 2
. Did you complete the replacement? |
- | Go to Step 13 | - |
| 12 | Replace the ECM. Refer to Control Module References
in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? |
- | Go to Step 13 | - |
| 13 |
|
- | Go to Step 2 | Go to Step 14 |
| 14 | 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 in Vehicle DTC Information | System OK |