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Home >> Audi >> 2012 >> A7 >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> 3.0L - Generic Scan Tool - Engine Code: CGXB (2 Of 2) >> St Generic Scan Tool >> Diagnosis And Testing >> Diagnostic Procedures >> Fuel Tank Leak Detection Control Module, Checking >> Checking wiring
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Checking wiring

-- Remove the Engine Control Module - J623 -. Refer to appropriate Service Information.

-- Using a Multimeter, Check the Fuel Tank Lead Detection Control Module -J909- electrical harness connector to the Engine Control Module electrical harness connector T94 for an open circuit.

-- also check the wiring from the Fuel Tank Lead Detection Control Module -J909- electrical harness connector terminal 1 to the Fuse 2 (on fuse panel F) -SF 2- for an open circuit or a short circuit to Ground (GND).

Fuel Tank Lead Detection Control Module -J909- electrical harness connector terminals: Engine Control Module electrical harness connector T94 terminal and the appropriate fuse. Refer to appropriate System Wiring Diagram for fuse positions
1 The appropriate fuse. Refer to appropriate System Wiring Diagram for fuse positions
3 38

Specified value: 1.5 Ω Max.

If the specified value was Not obtained:

-- Check the wiring connection for an open circuit or short circuit.

-- Check the wiring connection for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

-- Repair the circuit and replace any open fuses.

-- Go to Final procedures.

If the specified value was obtained:

-- Replace the Engine Control Module - J623 -. Refer to appropriate Service Information.

-- Go to Final procedures.



-- Remove the Engine Control Module - J623 -. Refer to appropriate Service Information.

-- Using a Multimeter, Check the Fuel Tank Lead Detection Control Module -J909- electrical harness connector to the Engine Control Module -J623 - electrical harness connector T94 for an open circuit.

Fuel Tank Lead Detection Control Module -J909- electrical harness connector terminal: Engine Control Module -J623- electrical harness connector T94 terminal:
2 69

Specified value: 1.5 Ω Max.

If the specified value was Not obtained:

-- Check the wiring connection for an open circuit or short circuit.

-- Check the wiring connection for damage, corrosion, loose or broken terminals.

-- If necessary, repair the faulty wiring connection.

-- Go to Final procedures.

If the specified value was obtained:

-- Replace the Fuel Tank Lead Detection Control Module -J909-. Refer to appropriate Service Information.

Final procedures 

-- Reinstall the left rear underbody protective cover.

  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 .