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Home >> Suzuki >> 2006 >> Verona Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Engine Control System - DTC P0030 Through P0175 >> DTC P0136: HO2S Circuit Bank 1 Sensor 2 >> DTC Troubleshooting
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DTC Troubleshooting

DTC TROUBLESHOOTING CHART

Step Action Value (s) Yes No
1 Did you perform the DIAGNOSTIC SYSTEM CHECK ? - Go to Step 2. Go to On-Board Diagnostic (OBD II) System Check .
2
  1. Start the engine.
  2. Allow the engine to reach operating temperature.
  3. Operate the engine at 1,500 rpm for 30 seconds.
  4. While observing the HO2S2 voltage parameter with a scan tool, quickly cycle the throttle from closed throttle to Wide Open Throttle (WOT), 3 times.

Did the HO2S2 voltage parameter change more than the specified value?		 200 mV Go to Step 3. Go to Step 4.
3
  1. Observe the Freeze Frame / Failure Records for this DTC.
  2. Turn the ignition OFF for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame / Failure Records.

Did the DTC fail this ignition?		 - Go to Step 4. Go to Intermittents .
4
  1. Turn the ignition OFF.
  2. Disconnect the Heated Oxygen Sensor (HO2S) 2.
  3. Turn the ignition ON, with the engine OFF.
  4. Observe the HO2S2 voltage parameter with a scan tool.

Is the HO2S2 voltage parameter less than the specified value?		 100 mV Go to Step 6. Go to Step 5.
5 Observe the HO2S2 voltage parameter with a scan tool.
Is the HO2S2 voltage parameter more than the specified value?		 800 mV Go to Step 7. Go to Step 8.
6 Test the HO2S2 high signal circuit for a short to ground.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 9.
7 Test the HO2S2 high signal circuit for a short to voltage.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 18.
8 Measure the voltage from the low signal circuit of the HO2S2 harness connector on the engine harness side to a good ground with a DMM.
Is the voltage more than the specified value?		 2 V Go to Step 10. Go to Step 11.
9 Test the HO2S2 high signal circuit for a short to the HO2S2 low signal circuit.
Did you find and correct the condition?		 - Go to Step 17. Go to Step 14.
10 Test the HO2S2 low signal circuit for a short to voltage.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 18.
11
  1. Connect a 3 A fused jumper wire between the high signal circuit of the HO2S2 harness connector on the engine harness side and a good ground.
  2. Observe the HO2S2 voltage parameter with a scan tool.

Is the HO2S2 voltage parameter less than the specified value?		 100 mV Go to Step 12. Go to Step 14.
12
  1. Remove the jumper wire from the previous step.
  2. Connect a 3 A fused jumper wire between the high signal circuit of the HO2S2 harness connector on the engine harness side and the low signal circuit of the HO2S2 harness connector on the engine harness side.
  3. Observe the HO2S2 voltage parameter with a scan tool.

Is the HO2S2 voltage parameter less than the specified value?		 100 mV Go to Step 15. Go to Step 13.
13 Test the HO2S2 low signal circuit for an open or high resistance.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 18.
14 Test the HO2S2 high signal circuit for an open or high resistance.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 18.
15 Test the HO2S2 heater low control circuit for a short to the HO2S2 high signal circuit or HO2S2 low signal circuit.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 16.
16
  1. The HO2S2 may be detecting a rich exhaust condition, a lean exhaust condition, or the HO2S may be contaminated. Inspect for the following conditions:
    • A silicon contaminated HO2S2.
    • Any water intrusion into the HO2S2 connector.
    • An exhaust leak between the HO2S2 and the engine.
    • Any vacuum leaks.
    • Engine oil contaminated with fuel.
    • An incorrect fuel pressure.
    • Any lean or rich fuel injectors.
  2. Repair any of the above or similar engine conditions as necessary.

Did you find and correct the condition?		 - Go to Step 21. Go to Step 17.
17 Test for shorted terminals and for poor connections at the HO2S2.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 19.
18 Test for shorted terminals and for poor connections at the ECM.
Did you find and correct the condition?		 - Go to Step 21. Go to Step 20.
19 Replace the HO2S2.
Did you complete the replacement?		 - Go to Step 21. -
20 Replace the ECM.
Did you complete the replacement?		 - Go to Step 21. -
21
  1. Clear the DTCs with a scan tool.
  2. Turn the ignition OFF for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Setting the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame / Failure Records.

Did the DTC fail this ignition?		 - Go to Step 2. Go to Step 22.
22 Check if any additional DTCs are set.
Are there any DTCs that have not been diagnosed?		 - Go to applicable DTC Table . System OK
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