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Catalyst Temperature Sensor 1 -G20-, CHECKING

Observe all safety precautions: SAFETY PRECAUTIONS 

View clean working conditions: CLEAN WORKING CONDITIONS 

Perform a preliminary check to verify the condition: PRELIMINARY CHECK .

Use only gold-plated terminals when servicing any component with gold-plated electrical harness connector terminals.

For wiring diagrams, component locations, and connector views, Refer to the applicable wiring diagram.

Special tools and workshop equipment required 

Test Conditions 

Test Procedure 

-- Engine MUST be at room temperature.

-- Disconnect the Catalyst Temperature Sensor l -G20- connector. -1-

Fig 1: Electrical Connectors
GWWA26-10747Courtesy of AUDI OF AMERICA, LLC

-- Using a multimeter, check the Catalyst Temperature Sensor l -G20- terminals 1 to 2 for resistance.

Specified value: 230 Ω (+/- 60 Ω) at room temperature.

If the specified value was Not obtained:

-- Replace the Catalyst Temperature Sensor l -G20-

If the specified value was obtained:

-- Turn the ignition switch ON.

-- Using a multimeter, check the Catalyst Temperature Sensor l -G20- terminals 1 to 2 for voltage.

Specified value: 3.32 V (+/-.4 V)

If the specified value was Not obtained:

-- Remove the Engine Control Module -J623-. Refer to the Repair Manual.

-- Using a multimeter, check the Catalyst Temperature Sensor l -G20- electrical harness connector terminals to the Engine Control Module -J623- electrical harness connector T94 terminals for an open circuit according to the wiring diagram.

Catalyst Temperature Sensor l -G20- electrical harness connector terminals Engine Control Module -J623- electrical connector T94 terminals
1 66
2 82

Specified value: 1.5 Ω Max.

If the specified value was Not obtained:

-- Check the wiring for an open, high resistance or short to ground.

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

-- If necessary, repair the faulty wiring connection.

If there was no fault found in the wiring and the voltage was not obtained:

-- Replace the Engine Control Module -J623-. Refer to the Repair Manual.

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 .