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Home >> Isuzu >> 2004 >> Axiom Base, 4WD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine DRIVEABILITY And Emissions - DTC P0101 To P0174 >> DTC P0154: O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1) >> Test Description
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Test Description

Number(s) below refer to the step number(s) on the Diagnostic Chart.

  1. 3. If the DTC P0154 test passes while the Failure Records conditions are being duplicated, an intermittent condition is indicated.
DTC P0154 - O2 SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 2 SENSOR 1)

Step Action Values Yes No
1 Was the "On-Board Diagnostic (OBD-II) System Check" performed? - Go to Step 2 Go to On-Board Diagnostic (OBD-II) System Check
2
  1. Install the Tech 2.
  2. Run the engine at operating temperature.
  3. The response rate is calculated from the rise and fall of these values (auto -correlation index). If the resulting code is not responsive to HO2S1, the code data is stored in memory.
Does the Tech 2 indicate Bank 2 HO2S1 voltage varying outside the specified values?		 250--500 mV Go to Step 3 Go to Step 4
3
  1. Ignition "ON", Engine "OFF".
  2. Review and record Tech 2 Failure Records data and note parameters.
  3. Operate the vehicle within Failure Records conditions as noted.
  4. Using a Tech 2, monitor "DTC" info for DTC P0154 until the DTC P0154 test runs.
  5. Note the test result.
Does the Tech 2 indicate DTC P0154 failed this ignition?		 - Go to Step 4 Refer to DIAGNOSTIC AIDS 
4 Check for a damaged harness.
Was a problem found?		 - Verify repair Go to Step 5
5 Check for a poor Bank 2 HO2S1 high and low circuit terminal connections at the Bank 2 HO2S1 harness connector and replace terminal(s) if necessary.
Did any terminals require replacement?		 - Verify repair Go to Step 6
6 Check for a poor Bank 2 HO2S1 high and low circuit terminal connections at the ECM and replace terminal(s) if necessary.
Did the terminal require replacement?		 - Verify repair Go to Step 7
7
  1. Ignition "OFF".
  2. With the ECM disconnected, check continuity of the Bank 2 HO2S1 high circuit.
  3. If the Bank 2 HO2S1 high circuit measures over 5.0 ohms, repair open or poor connection as necessary.
Was a Bank 2 HO2S1 high circuit problem found and corrected?		 - Verify repair Go to Step 8
8
  1. Ignition "OFF".
  2. With the ECM disconnected, check continuity of the Bank 2 HO2S1 low circuit.
  3. If the Bank 2 HO2S1 low circuit measures over 5.0 ohms, repair open or poor connection as necessary.
Was a Bank 2 HO2S1 low circuit problem found and corrected?		 - Verify repair Go to Step 9
9
  1. Ignition "ON", Engine "OFF".
  2. Disconnect Bank 2 HO2S1 and jumper the HO2S high and low circuits (ECM side) to ground.
  3. Using a Tech 2, monitor Bank 2 HO2S1 voltage.
Is the Bank 2 HO2S1 voltage in the specified range?		 0--10 mV Go to Step 10 Go to Step 11
10 Replace Bank 2 HO2S 1.
Is the action complete?		 - Verify repair -
11 Install the test ECM.
Program the test ECM (Immobilizer system). Refer to IMMOBILIZER SYSTEM .
Check the OBD-II test for following condition:
  1. When the ignition is "ON", turn on the MIL and RPL (RPL is put out after 3 second).
  2. When the engine is started.

Did the DTC disappear?		 - Go to Step 12 Go to Step 2
12 Replace the original ECM.
Check the poor connection between the ECM and ECM connector.
Recheck the OBD -II test again.
When the engine is started.
Did the DTC disappear?		 - Verify repair Go to Step 13
13 Disconnect the ABS control unit connector.
Reprogramming the original ECM. (Engine control and Immobilizer control)
Recheck the OBD -II.
Did the DTC disappear?		 - Verify repair Go to Step 14
14 Replace the ECM.
Recheck the OBD -II test again.
Did the DTC disappear?		 - Verify repair Refer to DIAGNOSTIC AIDS 
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