DIN 72552 Terminal Designations 
source:  Bosch Automotive Electrics/Electronics book 
(not all terminals listed will be found on all models)

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Ignition coil, distributor

1    Low voltage
4    High tension
7    Control contact (pulse generator/trigger box)

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15    Switched Plus downstream of battery (output of ignition and starting switch)

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15a    Output at ballast resistor to ignition coil and starter

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16    Output at the trigger box to the ignition coil and the control unit

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30    Input from Positive battery terminal (direct)

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31 Return line to Negative battery terminal or ground (direct)

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31d    Control contact (pulse generator)

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50    Starter, Starter control (direct)

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85    Switching Relay
        Output, actuator
        (negative winding and/or ground)
        Input actuator
86    Start of winding

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87    Changeover Contact

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88    Relay contact for make contact
        Input

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88a   Relay contact for make contact and changeover contact (make side)
        First ouptut

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Generator and generator regulator

B+    Battery Positive
B-    Battery Negative
D+    Dynamo Positive
D-    Dynamo Negative
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U    3-phase alternator
V,W    3-phase terminals