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Home >> Isuzu >> 2004 >> Axiom Base, RWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine DRIVEABILITY And Emissions - DTC P0101 To P0174 >> DTC P0134: O2 Sensor Circuit No Activity Detected (Bank 1 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 P0134 test passes while the Failure Records conditions are being duplicated, an intermittent conditions is indicated.
DTC P0134 - O2 Sensor Circuit No Activity Detected (Bank 1 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. As described in 'Conditions For Setting The DTC". Running time must exceed 2 minutes and 30 seconds.
Does the Tech 2 indicate Bank 1 HO2S1 voltage varying outside the specified values?
250-500 mV Go to Step 3 Go to Step 4
3
  1. Ignition "ON", Engine "OFF". Review and record Tech 2 Failure Records data and note parameters.
  2. Operate the vehicle within Failure Records conditions as noted.
  3. Using a Tech 2, monitor "DTC" info for DTC P0134 until the DTC P0134 test runs.
  4. Note the test result.
Does the Tech 2 indicate DTC P0134 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 poor Bank 1 HO2S1 high and low circuit terminal connections at the Bank 1 HO2S1 harness connector and replace terminal(s) if necessary.
Did any terminals require replacement?
- Verify repair Go to Step 6
6 Check for poor Bank 1 HO2S1 high and low circuit terminal connections at the ECM and replace terminals if necessary.
Did any terminals require replacement?
- Verify repair Go to Step 7
7
  1. Ignition "OFF".
  2. With the ECM disconnected, check continuity of the Bank 1 HO2S1 high circuit.
  3. If the Bank 1 HO2S1 high circuit measures over 5.0 ohms, repair open or poor connection as necessary.
Was a Bank 1 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 1 HO2S1 low circuit.
  3. If the Bank 1 HO2S1 low circuit measures over 5 ohms, repair open or poor connection as necessary.
Was a Bank 1 HO2S1 low circuit problem found and corrected?
- Verify repair Go to Step 9
9
  1. Ignition "ON", Engine "OFF".
  2. Disconnect Bank 1 HO2S1 and jumper the HO2S high and low circuits (ECM side) to ground.
  3. Using a Tech 2, monitor Bank 1 HO2S1 voltage.
Is Bank 1 HO2S1 voltage in the specified range?
0-10 mV Go to Step 10 Go to Step 11
10 Replace Bank 1 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 seconds).
  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