Ribbed heat exchanger and other changes (CA only)

In order to insure that the heater output meets the requirements of extreme climactic zones the heater system has been changed.

1. The engine heat exchangers are finned
2. The hot air fan has a two stage switch:
   
   • First stage (current draw 70 Watt)
   • Second stage (current draw 160 Watt)

The two stage switch for the fan operates automatically. The first stage is limited to stationary heating operation. The second stage is automatically switched on when the engine is started (voltage at regulator swicth D+). This ensures that the current draw is limited during stationary operation.

Service installation into previously produced vehicles is not intended.

 

 

Wiring diagram for the BA 4 heater (for 1972 models)

1. Warning lamp
2. Main switch
3. Electronic switch
4. Fuel pump
5. Temperature sensor
6. Plug housing
   6a - Multi point plug (Temperature switch, relay)
   6b - Plug housing (VW 411 wagon)
   6c - Plug housing of the combustion air blower cable harness
7. Cable connector
8. Ignition coil
9. Overheating switch
10. Glow/Spark plug
11. Angled plug with ignition cable
12. Thermo switch
13. Combustion air fan motor
14. Contact breaker for pump
15. Contact breaker for ignition
16. Overheating fuse 8 amp.
17. Hot air motor
18. Safety switch
19. Double relay
20. Fuse 16 amp.
21. To terminal 30 of safety switch
22. Suppression choke
23. Temperature regulating switch
24. Time switch
25. Operational readiness switch
26. Clock contact
27. To parking light
28. To ignition/starter lock
29. To starter (terminal 30)
30. To regulator switch
31. To lighting switch (terminal 30)
32. Series resistance for hot air fan

 

ro	=	red		bl	=	blue
sw	=	black		br	=	brown
ge	=	yellow		ws	=	white
gn	=	green

The cable which is shown dotted - from the 16 amp. fuse (20) to the plug housing (6b) - belongs to the VW 411 wagon.