Conditions for Clearing the MIL/DTC
WARNING: This page is about a different car, the 2004 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
- 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 P0141
| 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-Engine Controls? | - | Go to Step 2 | Go to Diagnostic System Check - Engine Controls |
| 2 |
|
390-520 mV | Go to Step 3 | Go to Step 4 |
| 3 |
|
- | Go to Step 4 | Go to Intermittent Conditions |
| 4 |
|
50 mV | Go to Step 9 | Go to Step 5 |
| 5 |
IMPORTANT:
Use a known good ground. DO NOT use the HO2S 2 heater low control circuit or the HO2S 2 low signal circuit. Probe the HO2S 2 heater ignition voltage circuit with a test lamp that is connected to a good ground. Refer to Probing Electrical Connectors
in Wiring Systems.Does the test lamp illuminate? |
- | Go to Step 7 | Go to Step 6 |
| 6 | Inspect the HO2S 2 heater ignition voltage fuse for an open. Is the fuse open? |
- | Go to Step 10 | Go to Step 16 |
| 7 |
|
15 mV | Go to Step 8 | Go to Step 12 |
| 8 |
|
5 Ω | Go to Step 17 | Go to Step 13 |
| 9 | Test the HO2S 2 high signal circuit for a short to the HO2S 2 heater low control circuit. Refer to Circuit Testing
,Wiring Repairs
, and Heated Oxygen Sensor (HO2S) Wiring Repairs
in Wiring Repairs. Did you find and correct the condition? |
- | Go to Step 20 | Go to Step 15 |
| 10 | Test the HO2S 2 heater ignition voltage circuit for a short to ground and replace the fuse. Refer to Circuit Testing
,Wiring Repairs
, and Heated Oxygen Sensor (HO2S) Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 20 | Go to Step 11 |
| 11 | Test the HO2S 2 heater ignition voltage circuit on the sensor side of the HO2S connector for a short to ground. Refer to Circuit Testing
in Wiring Systems. Is the sensor shorted to ground? |
- | Go to Step 18 | Go to Intermittent Conditions |
| 12 | Test the HO2S 2 high signal circuit for an open or high resistance condition. Refer to Circuit Testing
, Wiring Repairs
, and Heated Oxygen Sensor (HO2S) Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 20 | Go to Step 15 |
| 13 | 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 20 | Go to Step 14 |
| 14 | Test for an intermittent and for a poor connection at the harness connector of the HO2S 2. Refer to Testing for Intermittent Conditions and Poor Connections
, Connector Repairs
, and Heated Oxygen Sensor (HO2S) Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 20 | Go to Step 18 |
| 15 | Test for an intermittent and for a poor connection at the harness connector of the PCM. 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 20 | Go to Step 19 |
| 16 | Repair the open or high resistance condition in the HO2S 2 heater ignition voltage circuit. Refer to Wiring Repairs
and Heated Oxygen Sensor (HO2S) Wiring Repairs
in Wiring Systems. Did you complete the repair? |
- | Go to Step 20 | - |
| 17 | Repair the circuit that measures high resistance. Refer to Wiring Repairs
and Heated Oxygen Sensor (HO2S) Wiring Repairs
in Wiring Systems. Did you complete the repair? |
- | Go to Step 20 | - |
| 18 | Replace the HO2S 2. Refer to Heated Oxygen Sensor Replacement - Position 2
. Did you complete the replacement? |
- | Go to Step 20 | - |
| 19 | Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement
. Did you complete the replacement? |
- | Go to Step 20 | Go to Step 2 |
| 20 |
|
- | Go to Step 2 | Go to Step 21 |
| 21 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? |
- | Go to Diagnostic Trouble Code (DTC) List | System OK |