Fuel Tank Lock Switch F314 , checking

The Fuel Tank Lock Switch F314 consists of a reed contact on fuel filler tube and a fuel tank cap with an embedded magnet. If fuel tank cap is not fully screwed on, the reed contact switches on an indicator in instrument cluster.

Special tools, testers and auxiliary items required 

• Portable multimeter V.A.G 1526 C

• Connector test set V.A.G 1594 C

• If indicator is lit, check the following points in order:

• Fuel tank cap is completely screwed on.
• Correct fuel tank cap (Identification: Threads are gray in color).

• Switch - arrow  - at fuel filler tube is fully inserted.
• Electrical malfunction in switch.
• Wiring connection to instrument cluster is faulty (check according to schematics).

Fuel Tank Lock Switch F314 , checking electrical 

Sedan: 

• Remove carpeting in luggage compartment.
• Fold forward right rear seat backrest, if necessary.

Wagon: 

• Remove left 1/3 backrest →
  • 72 - SEAT - FRAMES
  • 72 - SEAT - FRAMES for BODY INTERIOR - CABRIOLET
  .
• Remove left side luggage compartment trim and dirt tray →
  • 70 - INTERIOR TRIM
  • 70 - INTERIOR TRIM for BODY INTERIOR - CABRIOLET
  .

All models: 

• Unbolt cover for locking flange in luggage compartment - arrows  -.

• Disconnect electrical connector - 2  -.

• Connect hand multimeter V.A.G 1526 between terminal - 1  - and - 2  - for resistance measurement.

Fuel tank cap	Specified value
Screwed on tight	∞ Ω
Not or incorrectly screwed on	Less than 1 Ω

If specifications are not obtained:

• Remove right rear wheel housing liner →
  • 66 EXTERIOR EQUIPMENT
  • 66 - EXTERIOR EQUIPMENT for BODY EXTERIOR - CABRIOLET
  .

• Replace Fuel Tank Lock Switch F314 - arrow  - , thereby unclipping and clipping in switch and electrical wiring at fuel filler tube.