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HEATED OXYGEN SENSOR (HO2S) INSPECTION [AJ] (VIN: JM0 LW10J300 301406-, JMZ LW69J7*# 307683-, JM8 LW28J**# 301514-, JM8 LW28A**# 301514- (Assumed))

BME014018860W02

  Note

  • Perform the following test only when directed.

## HO2S Voltage Inspection

1. Turn the ignition switch to LOCK.

2. Connect the WDS or equivalent to the DLC-2.

3. Warm up the engine to normal operating temperature.

4. Using the WDS or equivalent, monitor the following:

  - Vehicle speed (PID: VSS)
  - Engine speed (PID: RPM)
  - HO2S voltage (PID: O2S11)

5. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.

6. Verify that the HO2S outputs a voltage of 0.6 V or more, one time or more, then verify that the HO2S voltage (PID: O2S11) is 0.3 V or less while decelerating as shown in the figure.

  • If not within the specification, inspect the HO2S for an open or short circuit. (See HO2S Circuit Open/Short Inspection.) Then if there is no malfunction in the wiring harness, replace the HO2S.

## HO2S Circuit Open/Short Inspection

1. Disconnect the PCM connector. (SeePCM REMOVAL/INSTALLATION [AJ] .)

2. Inspect the following wiring harness for open or short circuit (Continuity check).

### Open circuit

  • If there is no continuity, the circuit is open. Repair or replace the harness.
  - HO2S (Front, RH) terminal A and 104 pin PCM terminal 18
  - HO2S (Front, RH) terminal B and 104 pin PCM terminal 20
  - HO2S (Rear, RH) terminal A and 104 pin PCM terminal 44
  - HO2S (Rear, RH) terminal B and 104 pin PCM terminal 20
  - HO2S (Front, LH) terminal A and 104 pin PCM terminal 19
  - HO2S (Front, LH) terminal B and 104 pin PCM terminal 20
  - HO2S (Rear, LH) terminal A and 104 pin PCM terminal 45
  - HO2S (Rear, LH) terminal B and 104 pin PCM terminal 20

### Short circuit

  • If there is continuity, the circuit is shorted. Repair or replace the harness.
  - HO2S (Front, RH) terminal A and body ground
  - HO2S (Front, RH) terminal A and power supply
  - HO2S (Front, RH) terminal B and power supply
  - HO2S (Rear, RH) terminal A and body ground
  - HO2S (Rear, RH) terminal A and power supply
  - HO2S (Rear, RH) terminal B and power supply
  - HO2S (Front, LH) terminal A and body ground
  - HO2S (Front, LH) terminal A and power supply
  - HO2S (Front, LH) terminal B and power supply
  - HO2S (Rear, LH) terminal A and body ground
  - HO2S (Rear, LH) terminal A and power supply
  - HO2S (Rear, LH) terminal B and power supply

## HO2S Heater Resistance Inspection

1. Disconnect the HO2S (front or rear) connector.

2. Measure the resistance between the following HO2S terminals.

  • HO2S (Front, RH) and HO2S (Rear, RH)

  - Terminal C and D

  • HO2S (Front, LH) and HO2S (Rear, LH)

  - Terminal C and D

  • If not as specified, replace the HO2S.
  • If the HO2S heater is okay, but PID value is out of specification, perform the "Circuit Open/Short Inspection".

Specification

  Front (RH, LH): 2-20 ohms
  Rear (RH, LH): 2-50 ohms

## HO2S heater Circuit Open/Short Inspection

1. Disconnect the PCM connector. (See PCM REMOVAL/INSTALLATION [AJ].)

2. Inspect the following wiring harness for open or short circuit (Continuity check).

### Open circuit

  • If there is no continuity, the circuit is open. Repair or replace the harness.
  - HO2S (Front, RH) terminal C and power supply
  - HO2S (Front, RH) terminal D and 104 pin PCM terminal 83
  - HO2S (Rear, RH) terminal C and power supply
  - HO2S (Rear, RH) terminal D and 104 pin PCM terminal 57
  - HO2S (Front, LH) terminal C and power supply
  - HO2S (Front, LH) terminal D and 104 pin PCM terminal 84
  - HO2S (Rear, LH) terminal C and power supply
  - HO2S (Rear, LH) terminal D and 104 pin PCM terminal 58

### Short circuit

  • If there is continuity, the circuit is shorted. Repair or replace the harness.
  - HO2S (Front, RH) terminal C and body ground
  - HO2S (Front, RH) terminal D and body ground
  - HO2S (Front, RH) terminal D and power supply
  - HO2S (Rear, RH) terminal C and body ground
  - HO2S (Rear, RH) terminal D and body ground
  - HO2S (Rear, RH) terminal D and power supply
  - HO2S (Front, LH) terminal C and body ground
  - HO2S (Front, LH) terminal D and body ground
  - HO2S (Front, LH) terminal D and power supply
  - HO2S (Rear, LH) terminal C and body ground
  - HO2S (Rear, LH) terminal D and body ground
  - HO2S (Rear, LH) terminal D and power supply