Topic:
Terminal designations:
In the electrical installations in motor vehicle technology, terminal designations are standardized. This prevents confusion (e.g. abroad) and makes it quicker to read in the diagram (2 digits instead of full texts). These designations are laid down in standard DIN 72552.
Below is the table of the most common designations:
| Ignition coil, distributor | |
| 1 | Low voltage |
| 4 | High voltage |
| 7 | Control contact |
| 15 | Switched positive (output ignition switch) |
| 15a | Switched positive after the ballast resistor of ignition coil and starter motor |
| Glow plug switch (diesel engines) | |
| 17 | Start |
| 19 | Glow |
| Battery | |
| 30 | Battery positive |
| 31 | Vehicle ground / battery negative terminal |
Electric motors | |
| 32 | Return line |
| 33 | Main connection |
| 33b | Shunt field |
| 33L | Direction of rotation Left |
| 33R | Direction of rotation Right |
| Flasher relay (pulse generator) | |
| 49 | Input |
| 49a | Flasher output with time interval |
| 49b | Output, second flasher relay |
| Starter motor | |
| 50 | Starter motor control (direct) |
| 50a | Battery changeover relay output for starter motor control |
| Wiper motors | |
| 53 | Wiper motor input (Positive) |
| 53a | Wiper (Positive) park switch |
| 53b | Wiper, shunt winding |
| 53c | Electric windshield washer pump |
| 53e | Wiper, brake winding |
| 53i | Wiper motor with permanent magnet and 3rd brush for higher speed |
| Lighting | |
| 54 | Brake lights |
| 54G | Rear fog light |
| L | Left direction indicators |
| R | Right direction indicators |
| 55 | Fog lamps |
| 56 | Headlamps |
| 56a | Main beam and warning lamp |
| 56b | Dipped beam |
| 56d | Headlight flasher |
| 57a | Parking lights |
| 57L | Parking lights Left |
| 57R | Parking lights Right |
| 58L | Lighting left |
| 58R | Lighting right, incl. side marker and license plate lighting |
| C1, 2 &3 | Indicator light 1, 2 &3 |
| Alternator and voltage regulator | |
| 61 | Alternator warning lamp |
| B+ | Battery positive |
| B- | Battery ground |
| D+ | Alternator positive |
| D- | Alternator negative (ground) |
| DF (1 & 2) | Alternator field (1 & 2) |
| U, V, W | Three-phase alternating current |
| Audio equipment | |
| 75 | Radio, cigarette lighter |
| 76 | Loudspeaker |
| Switch | |
| Break and changeover contact switch: | |
| 81 | Input |
| 81a | First output, break contact |
| 81b | Second output, break contact |
| 82 | Input |
| 82a | First output |
| 82b | Second output |
| 82y | Second input |
| 82z | First input |
| Multi-position switch: | |
| 83 | Input |
| 83a | Output, position 1 |
| 83b | Output, position 2 |
| 83L | Output, position Left |
| 83R | Output, position Right |
| Switching relays | |
| 85 | Relay negative side control current |
| 86 | Relay positive side control current |
| 86a | Start of winding or first winding |
| 86b | Winding tap or second winding relay contact |
| 87 | Relay main current connection |
| 87a | Relay main current connection 2 (changeover or break relay) |
| 88b | Normally open contact |
| 88 | Relay contact input for break and changeover contact |
| 88a | Normally closed contact 2 |
| 88b | Normally open contact 2 |
| 88c | Third output |
| Extra | |
| 52 | Trailer signal |
| 54g | Solenoid valves for trailer brakes |
| 77 | Door signal |