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Info guides and mods

Connection Reference Numbers

Modification Details

KL is the abbreviation for 'klemme' which is the German term for connector / connection.
The Klemme KL code tells you how a power or earth wire functions on a diagram.

Used On Smart Wiring Diagrams

KL15 is ignition switched live
KL30 is battery permanent live
KL31 is battery negative, connected all the time

Not Used On Smart Wiring Diagrams

KL50 is ignition position #3 (start)
KLR means ignition switch position #1 (accessory)

Ignition Switch Position

Ign 1 - KLR
Ign 2 - KL15
Ign 3 - KL50

Smart Ignition Switch Positions

Smart only use 3 positions unlike many other cars that use 4.


How Is This Handy?

Well, to be honest, for you it might not be but I look at smart wiring diagrams every day and I really
needed somewhere I could put this information so I could quickly view it to refresh my memory.

DIN 72552

Ignition coil

1 Low voltage

4 High voltage

4a From ignition coil I, terminal 4

4b From ignition coil II, terminal 4

15 Switched positive after battery (ignition-switch output)

15a Output at the series resistor to the ignition coil and to the starter

Glow-plug and starter switch

17 Start

19 Preglow


30 Line from battery positive terminal (direct)

30a Battery changeover 12/24 V Line from battery II positive terminal

31 Return wire from battery negative or ground (direct)

31b Return wire to battery negative or ground via switch or relay (switched negative)

Battery changeover relay 12/24 V

31a Return line to battery II negative

31c Return line to battery I negative

Electric motors

32 Return line

33 Main terminal

33a Self-parking

33b Shunt field

33f for second reduced-rpm operation

33g for third reduced-rpm operation

33h for fourth reduced-rpm operation

33L Rotation to left (counterclockwise)

33R Rotation to right (clockwise)

45 Separate starter-motor relay, output; starter, input (primary current)

Dual starter
45a Starter I output, Starter I and II input 
45b Starter II output 
48 Terminal on starter and start repeating relay (monitoring the starting process) 
Turn-signal flasher
49 Input 
49a Output 
49b Output to second flasher circuit 
49c Output to third flasher circuit 
50 Starter control (direct)
Battery changeover relay
50a Output for starter control 
Starter control 
50b In parallel operation of two starter motors with sequence control 
Starting relay for sequence control of engagement current in parallel operation of two starter motors 
50c Input at starting relay for starter I 
50d Input at starting relay for starter II 
Start-locking relay 
50e Input 
50f Output
Start repeating relay 
50g Input 
50h Output 
Wiper motors
53 Wiper motor, input (+)

53a Wiper (+), self-parking

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)


55 Fog lamps

56 Headlamps

56a High beam with indicator lamp

56b Low beam (dipped beam)

56d Headlamp-flasher contact

57a Parking lamp

57L Parking lamp, left

57R Parking lamp, right

58 Side-marker, tail, license-plate and instrument lamps

58d Adjustable instrument lighting
58L left

58R right

Alternators and voltage regulators

61 Alternator charge indicator

B+ Battery positive terminal

B– Battery negative terminal

D+ Alternator positive terminal

D– Alternator negative terminal

DF Alternator field winding

DF1 Alternator field winding 1

DF2 Alternator field winding 2

U, V, W Three-phase terminals

Audio systems

75 Radio, cigarette lighter

76 Loudspeaker


Normally closed contact/changeover contact

81 Input

81a 1st output, NC side

81b 2nd output, NC side

Normally open contact

82 Input

82a 1st output

82b 2nd output

82z 1st input

82y 2nd input

Multiple-position switch

83 Input

83a Output, position 1

83b Output, position 2

83L Output, position left

83R Output, position right

Current relay

84 Input, output, relay contact
84a Output, drive

84b Output, relay contact

Switching relay 
85 Output, drive (end of winding negative or ground) 
86 Input, drive (start of winding)

86a Start of winding / 1st winding
86b Winding tap / 2nd winding

Relay contact for NC contact and changeover contact

87 Input
87a 1st output (NC side) 
87b 2nd output

87c 3rd output

87z 1st input
87y 2nd input 
87x 3rd input
Relay contact for NO contact
88 Input
Relay contact for NO contact and changeover contact (NO contact side)
88a 1st output
88b 2nd output 
88c 3rd output
Relay contact for NO contact
88z 1st input
88y 2nd input 
88x 3rd input
Turn-signal lamp (turn-signal flasher) 
C 1st indicator light 
C0 Main terminal for check circuits separate from flasher 
C2 2nd indicator lamp
C3 3rd indicator lamp (e.g for dual trailer operation)
L Left-side turn-signal lamp 
R Right-side turn-signal lamp

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