Oxygen Sensor Heater In Center Catalytic Converter, Checking

Special tools and workshop equipment required 

• Multimeter.
• Wiring diagram.

Test Requirements 

• The Heated Oxygen Sensor (HO2S) -G465- heater fuse is OK.
• Battery voltage at least 12.5 volts.
• All electrical consumers such as, lights and rear window defroster, switched off.
• Vehicles with automatic transmission, shift selector lever into position "P" or "N".
• A/C switched off.
• Ground connections between engine/transmission/chassis OK.
• Ignition switched OFF.

Test Procedure 

-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK 

Start Diagnosis 

-- Remove the engine cover with air filter.

Checking Internal Resistance 

-- Disconnect the Heated Oxygen Sensor (HO2S) -G465- electrical harness connector.

-- Using a multimeter, check the Heated Oxygen Sensor (HO2S) -G465- terminals 1 and 2 for correct resistance.

Specified Value: 7.5 To 15.0 Ω (At Approx. 20 °C) 

If The Specified Value Was Not Obtained: 

-- Replace the Heated Oxygen Sensor (HO2S) -G465-.

If The Specified Value Was Obtained: 

Checking Voltage Supply 

-- Turn the ignition switch ON

-- Using a multimeter, check the Heated Oxygen Sensor (HO2S) -G465- electrical harness connector terminal 1 to engine ground for voltage.

Specified Value: Battery Voltage. 

-- Switch the ignition OFF.

If The Specified Value Was Not Obtained: 

-- Check the wiring for an open, high resistance or short to Ground and replace any open fuse.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

If The Specified Value Was Obtained: 

Checking Ground Activation 

-- Remove the Engine Control Module (ECM) -J623-.

-- Using a multimeter, check the Heated Oxygen Sensor (HO2S) -G465- electrical harness connector terminal 2 to the Engine Control Module (ECM) -J623- electrical harness connector T94 terminal for an open circuit. Refer to Appropriate System Diagrams for pin locations.

2009 - 2010 Models 

Heated Oxygen Sensor (HO2S) -G465- electrical harness connector terminal:	Engine Control Module (ECM) -J623- electrical connector T94 terminal:
2	7

2011 > 

Heated Oxygen Sensor (HO2S) -G465- electrical harness connector terminal:	Engine Control Module (ECM) -J623- electrical connector T94 terminal:
2	51

Specified Value: 1.5 Ω Max. 

If The Specified Value Was Not Obtained: 

-- Check the wiring for an open or high resistance.

-- Check the electrical harness connector for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

If No Malfunction Is Detected In The Wiring And The Voltage Supply Was Ok: 

-- Replace the Engine Control Module (ECM) -J623-.

-- Install the engine cover with air filter.

Final Procedures 

After the repair work, the following work steps must be performed in the following sequence:

1. Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
2. If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
3. If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .