Conditions for Clearing the MIL/DTC
- 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 P0140
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) 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 |
|
390-520 mV | Go to Step 3 | Go to Step 4 |
| 3 |
|
- | Go to Step 4 | Go to Intermittent Conditions |
| 4 |
|
500 mV | Go to Step 8 | Go to Step 5 |
| 5 | Measure the voltage from the HO2S 2 low signal circuit, on the engine harness side, to a good ground with a DMM. Refer to Circuit Testing
. Is the voltage more than the specified value? |
100 mV | Go to Step 9 | Go to Step 6 |
| 6 |
|
15 mV | Go to Step 7 | Go to Step 10 |
| 7 |
|
15 mV | Go to Step 12 | Go to Step 11 |
| 8 | Test the HO2S 2 high signal circuit for a short to voltage. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
- | Go to Step 17 | Go to Step 14 |
| 9 | Test the HO2S 2 low signal circuit for a short to voltage. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
- | Go to Step 17 | Go to Step 14 |
| 10 | Test the HO2S 2 high signal circuit for an open or high resistance. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
- | Go to Step 17 | Go to Step 14 |
| 11 | Test the HO2S 2 low signal circuit for an open or high resistance. Refer to Circuit Testing
and Wiring Repairs
. Did you find and correct the condition? |
- | Go to Step 17 | Go to Step 14 |
| 12 | Inspect for the following that may affect the HO2S operation:
NOTE:
Refer to Silicon Contamination of Heated Oxygen Sensors Notice
in Cautions and Notices.
NOTE:
Refer to Heated Oxygen and Oxygen Sensor Notice
in Cautions and Notices.
Did you find and correct the condition? |
- | Go to Step 17 | Go to Step 13 |
| 13 | Test for shorted terminals and poor connections at the HO2S 2. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
- | Go to Step 17 | Go to Step 15 |
| 14 | Test for shorted terminals and poor connections at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
. Did you find and correct the condition? |
- | Go to Step 17 | Go to Step 16 |
| 15 |
NOTE:
Refer to Heated Oxygen Sensor (HO2S) Resistance Learn Reset Notice
in Cautions and Notices. Replace the HO2S 2. Refer to Heated Oxygen Sensor Replacement - Position 2
.Did you complete the replacement? |
- | Go to Step 17 | - |
| 16 | Replace the PCM. Refer to Control Module References
for replacement, setup, and programming. Did you complete the replacement? |
- | Go to Step 17 | - |
| 17 |
|
- | Go to Step 2 | Go to Step 18 |
| 18 | Observe the Capture Info with a scan tool. Are there any DTCs that have not diagnosed? |
- | Go to Diagnostic Trouble Code (DTC) List - Vehicle | System OK |