Identification of electrical circuits depending on the engine (VW Transporter T4)

Due to the large volume, it is impossible to keep track of all the electrical diagrams for each model year. However, you can get your bearings on the current electrical diagram, even if the car belongs to a different year of production, since the changes usually affect only individual parts.

Designation of electrical circuits of engines

Engine	Letter designation	Electrical diagram
2.0 l/62 kW	AAS	Look subsection 10.20.7, subsection 10.20.8, subsection 10.20.9, subsection 10.20.10, subsection 10.20.11, subsection 10.20.12, subsection 10.20.13, subsection 10.20.14, subsection 10.20.15, subsection 10.20.16, subsection 10.20.17, subsection 10.20.18, subsection 10.20.19, subsection 10.20.20, subsection 10.20.21, subsection 10.20.22, subsection 10.20.23, subsection 10.20.24, subsection 10.20.25, subsection 10.20.26, subsection 10.20.38, subsection 10.20.39, subsection 10.20.40
2.5 l/82 kW	AAF	Look subsection 10.20.15, subsection 10.20.16, subsection 10.20.17, subsection 10.20.18, subsection 10.20.19, subsection 10.20.20, subsection 10.20.21, subsection 10.20.22, subsection 10.20.23, subsection 10.20.24, subsection 10.20.25, subsection 10.20.26, subsection 10.20.38, subsection 10.20.39, subsection 10.20.40
1.9 l/45 kW	1X	Look subsection 10.20.27, subsection 10.20.28, subsection 10.20.29, subsection 10.20.30, subsection 10.20.31, subsection 10.20.32, subsection 10.20.33, subsection 10.20.38, subsection 10.20.39, subsection 10.20.40
1.9 l/50 kW	AWD	Look subsection 10.20.34, subsection 10.20.35, subsection 10.20.38, subsection 10.20.39, subsection 10.20.40
2.4 l/57 kW	AAV	Look subsection 10.20.36, subsection 10.20.37, subsection 10.20.38, subsection 10.20.39, subsection 10.20.40

Relay kit

The number stamped on the corresponding relay is indicated in brackets behind the relay name.

• 1. Air conditioner relay (13)
• 2. Relay for rear window wipers with automatic intervals (72)
• 3. Digifant control unit relay (30)
• 4. Unloading relay contact X (18)
• 5. Low coolant indicator control unit (42)
• 6. Hazard warning relay (21) or trailer hazard warning relay (22)
• 7. Headlight washer system relay (33)
• 8. Relay for automatic intervals of washing and cleaning of glass (19)
• 9. Seat belt warning system control unit (27, 34)
• 10. Fog light relay (53)
• 11. Two-tone signal relay (53) or horn jumper plug
• 12. Intake air heater relay (1) or fuel pump relay (80)
• 13. Intake air heating relay (1) or automatic glow time control unit (102)
• 14. Radiator fan re-switching control unit (31) or additional water pump relay (53)
• 15. Additional water pump fuse
• 17. Driver's seat heating control unit (59)
• 18. Control unit for heating the seat next to the driver (59)
• 19. Air conditioner relay (56)