DIN Standard Terminal Definitions

You know those numbers on the back of switches, relays, panels and more? They are the DIN standard terminal numbers. They can help you troubleshoot electrical problems. For example, Terminal 15 is ignition on power. Read on for the big list!

Special thanks to Nick (vwpieces on VWVortex.com) for this information!

Terminal Designations (Excerpts from DIN Standard 72 552) The terminal designations do not identify the conductors, because device with different terminal designations can be connected at the two ends of each conductor. If the number of terminal designations is not sufficient (multiple-contact connections), the terminals are consecutively numbered using numbers or letters whose representations of specific functions are not standardized.

Terminal Definition
IGNITION
1 Ignition coil,
ignition distributor, low voltage
Ignition
distributor with two separate electrical circuits
1a to ignition contact
breaker I
1b to ignition contact
breaker II
2 short-circuit
terminal (magneto ignition)
4 Ignition coil,
ignition distributor, high voltage
Ignition
distributor with two separate electrical circuits
4a from ignition coil
I, terminal 4
4b from ignition coil
II, terminal 4
15 Switched +
downstream of battery
(output of ignition/driving switch)
15a Output at dropping
resistor to ignition coil and starter
GLOW
PLUG AND STARTER SWITCH
17 Start
19 Preheat
BATTERY
30 input from + battery
terminal, direct
30a input from +
terminal of battery II
(12/24 V series-parallel battery switch)
31 Return line to
battery – battery terminal or ground, direct
31b Return ine to
negative battery terminal or ground, via switch or
relay
(switched negative)
(12/24 V
series-parallel battery)
31a Return line to –
terminal of battery II
31c Return line to –
terminal of battery I
ELECTRIC MOTORS
32 Return line
(Polarity reversal possible at terminals 32-33)
33 Main terminal
connection
(Polarity reversal possible at terminals 32-33)
33a Self-parking
switch-off
33b Shunt field
33f For second
lower-speed range
33g For third
lower-speed range
33h For fourth
lower-speed range
33L Counterclockwise
rotation
33R Clockwise rotation
STARTER
45 Separate starter
relay output; starter input (main current)
45a Output, starter I
Input, starters I and II (Two-starter parallel
operation)
45b Output, starter II
(Two-starter parallel operation)
48 Terminal on starter
and on start-repeating relay for monitoring starting
procedure
TURN
SIGNAL FLASHER
49 Input
49a Output
49b Output, second
turn-signal circuit
49c Output, third
turn-signal circuit
STARTER
50 Starter control
(direct)
50a Output for starter
control
(Series-parallel battery switch)
50b Starter control with
parallel operation of two starters with sequential
control
50c Input at starting
relay for starter I
(Starting relay for sequential control of the
engagement current during parallel operation of two
starters)
50d Input at starting
relay for starter I
(Starting relay for sequential control of the
engagement current during parallel operation of two
starters)
50e Input, Start-locking
relay
50f Output,
Start-locking relay
50g Input,
Start-repeating relay
50h Output,
Start-repeating relay
ALTERNATOR
51 DC voltage at
rectifier
51e DC voltage at
rectifier with choke coil for daytime driving
TRAILER SIGNALS
52 Signals from trailer
to towing vehicle, general
WIPER
MOTOR
53 Wiper motor, input
(+)
53a Wiper (+),
self-parking switch-off
53b Wiper (shunt
winding)
53c Electric
windshield-washer pump
53e Wiper (brake
winding)
53i Wiper motor with
permanent magnet and third brush (for higher speed)
TRAILER SIGNAL
54 For lamp
combinations and trailer plug connections
TRAILER STOP LAMP
54g Pneumatic valve for
additional retarding brake, electromagnetically
actuated
LIGHTING
55 Fog lamps
56 Headlamp
56a High beam, high-beam
indicator lamp
56b Low beam
56d Headlamp-flasher
contact
57 Side-marker lamp:
motorcycles, mopeds. Abroad also cars, trucks, etc.
57a Parking lamp
57L Parking lamp, left
57R Parking lamp, right
58 Side-marker lamps,
tail lamps, license-plate lamps and instrument-panel
lamps
58b Tail-lamp changeover
for single-axle tractors
58c Trailer
plug-and-receptacle assembly for single-conductor
tail-lamp cable with fuse in trailer
58d Variable-intensity
instrument-panel lamp, tail-lamp and side-marker
lamp
58L Side-marker lamp,
left
58R Side-marker lamp,
right; license-plate lamp
ALTERNATOR (magneto, generator)
59 AC voltage, output,
rectifier, input
59a Charging armature,
output
59b Tail-lamp armature,
output
59c Stop-lamp armature,
output
61 Alternator
charge-indicator lamp
TONE-SEQUENCE CONTROL DEVICE
71 Input
71a Output to horns 1 &
2, low
71b Output to horns 1 &
2, high
72 Alarm switch
(rotating beacon)
INTERIOR
75 Radio, cigarette
lighter
76 Speaker
77 Door-valve
control/td>
SWITCHES
Break-contact and changeover switches
81 Input
81a 1st output, break
side
81b 2nd output, break
side
Make-contact switches
82 Input
82a 1st output
82b 2nd output
82z 1st input
82y 2nd input
Multiple-position switches
83 Input
83a Output, position 1
83b Output, position 2
83L Output, left-hand
position
83R Output, right-hand
position
CURRENT RELAY
84 Input, actuator and
relay contact
84a Output, actuator
84b Output, relay
contact
SWITCHING RELAY
85 Output, actuator
(end of winding to ground or negative)
86 Start of winding
86a Start of winding or
1st winding
86b Winding tap or 2nd
winding
Relay
contact for break and changeover contacts
87 Input
87a 1st output (break
side)
87b 2nd output
87c 3rd output
87z 1st input
87y 2nd input
87x 3rd input
Relay
contact for make contact
88 Input
Relay
contact for make and changeover contacts (make side)
88a 1st output
88b 2nd output
88c 3rd output
Relay
contact for make contact
88z 1st input
88y 2nd input
88x 3rd input
ALTERNATOR and VOLTAGE REGULATOR
GENERATOR and GENERATOR REGULATOR
B+ Battery positive
B- Battery negative
D+ Dynamo postive
D- Dynamo negative
DF Dynamo field
DF1 Dynamo field 1
DF2 Dynamo field 2
Alternator with separate rectifier
J Excitation winding
positive
K Excitation winding
negative
Mp Center point
terminal
U,V,W Alternator terminals
DIRECTION INDICATOR (turn-signal flasher)
C First indicator lamp
C0 Main terminal
connection for separate indicator circuits actuated
by the turn-signal switch
C2 Second indicator
lamp
C3 Third indicator lamp
(e.g., when towing two trailers)
L Turn-signal lamps,
left
R Turn-signal lamps,
right

From Bosch Automotive Handbook, 3rd Edition