Fuel Tank Leak Detection Control Module, Checking: Notes

Observe all safety precautions: SAFETY PRECAUTIONS .

View clean working conditions: CLEAN WORKING CONDITIONS .

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 appropriate System Wiring Diagram.

The following procedure is used to diagnose the Fuel Tank Lead Detection Control Module -J909- which is controlled by Engine Control Module -J623-.

Special Tools And Workshop Equipment Required 

• Multimeter.
• Wiring Diagram.

Test Requirements 

• The Engine Component Power Supply Relay -J757- OK.
• The Fuse -SF2- OK.
• The fuel filter OK.
• The parking brake engaged.
• The battery voltage at least 12.5 V.
• The selector lever of automatic transmission in position "P" or "N".
• All electrical consumers switched OFF.
• A/C switched OFF.
• The fuel tank at least ¹ /₄ filled.
• The ignition switched OFF.

Test Procedure 

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

Start Diagnosis 

-- Remove the left rear underbody protective cover.

-- Using a Multimeter, Check the Fuel Tank Lead Detection Control Module -J909- electrical harness connector terminals 1 to 3 for voltage.

Fig 1: Disconnecting Fuel Tank Lead Detection Control Module

Courtesy of AUDI OF AMERICA, LLC

-- Switch the ignition ON.

Specified value: Battery voltage.

-- Switch the ignition OFF.

-- Continue test according to the following table: