Bosch Terminal Designations for Automotive Wiring
Bosch terminal designations, courtesy Joel Walker.
From Bosch Automotive Handbook, 3rd edition
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 ----------------------------------------------------------------------- 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 ------------------------------------------------------------------------ Cross-reference for old and new terminal designations in accordance with DIN 72 552. Only terminal designations whose significance has altered are given.
OLD NEW 1 1, 53(wiper), 53e 2 2, 53e 3 53, 53b(wiper) 4 4, 53a, 53b(wiper) 15 15, 49(turn-signal flasher) 15+ 49 15/54 15, 49, 54 16 15a, 15 30 30, 33(motor) 30/51 30, 87, 88(relay) 30f 45 30h 45, 45a 30h I 45a 30h II 45b 30L 33L (motors) 30R 33R (motors) 31 31, 31c, 32(motors) 31a 31a, 31c 31B- B- 50 50, 50b, 50f, 50h 50a 50, 50a, 50e, 50g 50b 50d 50k 50d 50 II 50c 51 51, 59, B+ 51 - 59 51a 59 51B+ B+ 54 54, 53a, 54g 54/15 15 54d 53(wiper) 54e 33b, 53b(wiper) 54L 49a 58 58, 58L, 58R 58b 58b, 58d 59 59a 85d 31b(alarm switch) B+30 B+ B+51 B+ D+/61 D+ D-/61 D- H 71 HL L (L54b) HR R (R54b) K C K0 C0 K1 C, C2 K2 C2 K3 C2, C3 K4 C2, C3 L54 L (L54) N 55 P C, 57a PL 57L PR 57R R R, 75 R54 R, (R54) R54b Rb S 49a, 53(wiper) S4 49a SBL (L54) SBR (R54) VL L VR R + 15, 49(turn-signal flasher) 53, 53a(wiper) +2 53a +15 49 - 1 (ignition coil), 31 ------------------------------------------------------------------------ and, while i'm at it, here's some interesting stuff:
Power consumption of vehicle electrical leads (average values)
Backup lamps 25W Battery ignition 20W Blower motor 80W Cigarette lighter 100W
Fog lights 35W each Fog warning lamp 35W (red fog light on rear) Glow plugs 100W each Headlamps, low beam 55W each
Headlamps, high beam 60W each Heated rear window 120W Horns and fanfare horns 25W...40W each Instrument-panel lamps 2W each
Interior lamp 5W License-plate lamp 10W Parking lamp 3W...5W Radio 10W...15W
Side-marker lamps 4W each Starting motor for truck 2.2kW...12kW Starting motor for car 0.8kW...3kW Stop lamps 18W each
Tail lamps 5W each Turn-signal lamps 21W each Vehicle heater 20W...60W Windshield wiper 90W

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