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Home >> Suzuki >> 2007 >> Reno Standard >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine - Diagnostic Codes (1 Of 4) >> DTC P0139: HO2S Slow Response Sensor 2 >> Troubleshooting
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DTC P0139: HO2S Slow Response Sensor 2: Troubleshooting

TROUBLESHOOTING CHART

Step Action Value(s) Yes No
1 Perform an ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK .
Is the system check complete?		 - Go to Step 2 Go to On-Board Diagnostic (OBD II) System Check
2
  1. Connect the scan tool to the Data Link Connector (DLC).
  2. Run the engine until it reaches operating temperature.
  3. Check for the Closed Loop operation.

Does the scan tool indicate the Closed Loop?		 - Go to Step 3 Go to Step 4
3
  1. Turn the ignition switch to LOCK.
  2. Review the Freeze Frame data and note the parameters.
  3. Operate the vehicle within the Freeze Frame conditions and Conditions for Setting the DTC.

Does the scan tool indicate the Closed Loop?		 - Go to Step 12 Go to Step 4
4
  1. Disconnect the HO2S connector.
  2. Jumper the oxygen sensor connector terminal 1 to ground.
  3. Turn the ignition switch to ON.

Does the scan tool read the heated oxygen sensor signal voltage the specified value?		 0.4 - 0.5 V Go to Step 5 Go to Step 8
5 Check the HO2S connector for malfunction terminals or poor connection and repair as necessary.
Is repair necessary?		 - Go to Step 12 Go to Step 6
6
  1. Run the engine at idle.
  2. Remove the jumper wire.
  3. Measure the voltage between the HO2S connector terminal 4 and ground.

Does the heated oxygen sensor voltage measure above the specified value?		 0.6 V Go to Step 7 Go to Step 11
7
  1. Turn the ignition switch to LOCK.
  2. Measure the voltage between the HO2S connector terminal 4 and ground.

Does the HO2S voltage measure above the specified value?		 0.3 V Go to Step 9 Go to Step 11
8 Repair the wire or the connector between the HO2S terminal 3 and the Engine Control Module (ECM) terminal C4 is open or a short to ground.
Is the repair complete?		 - Go to Step 11 Go to Step 9
9 Repair the wire and the connector terminal between the HO2S connector terminal 4 and the ECM connector terminal C57 is open or a short to ground.
Is the repair complete?		 - Go to Step 12 Go to Step 10
10
  1. Turn the ignition switch to LOCK.
  2. Replace the ECM.
  3. Perform the diagnostic system check .

Is the repair complete?		 - System OK -
11 Replace the HO2 sensor.
Is the repair complete?		 - Go to Step 12 -
12
  1. Clear any DTCs from the ECM.
  2. Perform the diagnostic system check .

Is the repair complete?		 - Go to Step 13 -
13 Check if any additional DTCs are set.
Are any DTCs displaced that have not been diagnosed?		 - Go to applicable DTC TABLE System OK
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