2015 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE

Electrical Specification

WARNING: This page is about a different car, the 2016 Subaru Outback and 2016 Subaru Legacy. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Body Control System Control Module I/O Signal Connector Terminal Identification
G10277462Courtesy of SUBARU OF AMERICA, INC.
Terminal No. Content Measuring condition Standard
(i84) No. 1 ←→ Chassis ground Turn output (left rear side) Left turn signal OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(i84) No. 2 - - -
(i84) No. 3 ←→ Chassis ground Shift lock solenoid output (CVT model)
  • IG ON
  • Shift lever P range
  • Stop light switch ON (brake pedal depressed)
 9 - 16 V
  • IG ON
  • Shift lever P range
  • Stop light switch OFF (brake pedal not depressed)
 Less than 1 V
(i84) No. 4 ←→ Chassis ground GND Always Less than 1 Ξ©
(i84) No. 5 ←→ Chassis ground Turn output (right rear side) Right turn signal OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(i84) No. 6 ←→ Chassis ground Door lock (driver's seat unlock) When UNLOCK signal is output Less than 1 V β†’ 9 - 16 V
(i84) No. 7 - - -
(i84) No. 8 ←→ Chassis ground Luggage/trunk light output Luggage/trunk light OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(i84) No. 9 ←→ Chassis ground Room light output Room light OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(i84) No. 10 ←→ Chassis ground ACC (model with keyless access with push button start system) ACC OFF β†’ ON Less than 1 V β†’ 9 - 16 V
Key-in switch (model without keyless access with push button start system) Ignition key not inserted β†’ inserted Less than 1 V β†’ 9 - 16 V
(i171) No. 1 - - -
(i171) No. 2 Main system CAN (L) - Communication line
(i171) No. 3 ←→ (i171) No. 4 Immobilizer antenna (B) When ignition key inserted Pulse generation
(i171) No. 4 ←→ Chassis ground Immobilizer antenna amplifier GND Always Less than 1 Ξ©
(i171) No. 5 - - -
(i171) No. 6 ←→ Chassis ground Opener switch (rear gate/trunk) Rear gate/trunk opener switch ON 9 - 16 V β†’ less than 1 V
(i171) No. 7 ←→ (i171) No. 8 - - -
(i171) No. 8 ←→ Chassis ground Illumination sensor GND Always Less than 1 Ξ©
(i171) No. 9 ←→ Chassis ground Key ring illumination (LED drive) Key ring OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(i171) No. 10 ←→ Chassis ground Map light output Map light OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(i171) No. 11 - - -
(i171) No. 12 ←→ Chassis ground Manual switch (unlock) Door unlock switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 13 ←→ Chassis ground Door switch (passenger's seat) Passenger's door closed β†’ open 9 - 16 V β†’ less than 1 V
(i171) No. 14 ←→ Chassis ground Door switch (rear seat LH) Rear seat LH door closed β†’ open 9 - 16 V β†’ less than 1 V
(i171) No. 15 ←→ Chassis ground Door switch (rear gate/trunk) Rear gate/trunk closed β†’ open 9 - 16 V β†’ less than 1 V
(i171) No. 16 ←→ Chassis ground Dimmer Hi switch Dimmer switch Hi beam OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 17 - - -
(i171) No. 18 ←→ Chassis ground Turn signal right Left turn signal OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(i171) No. 19 ←→ Chassis ground Lighting II switch (redundant circuit) Lighting switch 2 OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 20 ←→ Chassis ground Lighting Lo relay output (redundant circuit) Lighting switch 2 OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 21 ←→ Chassis ground Power supply for lighting relay (redundant circuit) ACC OFF β†’ ON (with keyless access with push button start system), or ignition key not inserted β†’ inserted (without keyless access with push button start system) Less than 1 V β†’ 9 - 16 V
(i171) No. 22 Main system CAN (H) - Communication line
(i171) No. 23 ←→ (i171) No. 4 Immobilizer antenna (A) When ignition key inserted Pulse generation
(i171) No. 24 ←→ (i171) No. 4 Immobilizer antenna amplifier power supply Ignition switch ON 4.5 V - 5.5 V
(i171) No. 25 ←→ Chassis ground P range switch AT shift lever, other than P range β†’ P range 9 - 16 V β†’ less than 1 V
(i171) No. 26 ←→ Chassis ground Security light When security light is illuminating Pulse generation
(i171) No. 27 ←→ (i171) No. 8 Illumination sensor power supply Ignition switch OFF β†’ ON Less than 1 V β†’ 5 V
(i171) No. 28 ←→ (i171) No. 8 Illumination sensor signal When lighting switch is at AUTO 0 - 5 V
(i171) No. 29 ←→ Chassis ground Pull cup illumination output
  • All doors closed
  • Lighting switch 1 OFF β†’ ON
 Less than 1 V β†’ 9 - 16 V
(i171) No. 30 - - -
(i171) No. 31 - - -
(i171) No. 32 ←→ Chassis ground Manual switch (lock) Door lock switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 33 ←→ Chassis ground Door switch (driver's seat) Driver's door closed β†’ open 9 - 16 V β†’ less than 1 V
(i171) No. 34 ←→ Chassis ground Door switch (rear seat RH) Rear seat RH door closed β†’ open 9 - 16 V β†’ less than 1 V
(i171) No. 35 ←→ Chassis ground Lighting I switch Lighting switch 1 OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 36 ←→ Chassis ground Dimmer Pass switch Dimmer switch Pass OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 37 ←→ Chassis ground Turn hazard switch Turn hazard switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 38 ←→ Chassis ground Turn signal left Turn signal switch left OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i171) No. 39 - - -
(i171) No. 40 - - -
(i81) No. 1 ←→ Chassis ground Rear washer switch Rear washer switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 2 ←→ Chassis ground Lighting II switch (control) Lighting switch 2 OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 3 ←→ Chassis ground Rear wiper switch (INT) Rear wiper switch INT OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 4 - - -
(i81) No. 5 - - -
(i81) No. 6 ←→ Chassis ground Door lock status switch passenger's seat Passenger's door lock β†’ unlock 9 - 16 V β†’ less than 1 V
(i81) No. 7 - - -
(i81) No. 8 - - -
(i81) No. 9 ←→ Chassis ground Towing switch Towing switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 10 Keyless UART - Communication line
(i81) No. 11 - - -
(i81) No. 12 Front washer switch Front washer switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 13 - - -
(i81) No. 14 - - -
(i81) No. 15 ←→ Chassis ground LANE OFF switch Lane departure warning OFF switch, OFF β†’ ON (when pressed) 9 - 16 V β†’ less than 1 V
(i81) No. 16 - - -
(i81) No. 17 ←→ Chassis ground Front fog light switch Front fog light switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 18 LIN - Communication line
(i81) No. 19 ←→ Chassis ground Rear wiper switch (ON) Rear wiper switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 20 ←→ Chassis ground Lighting AUTO switch Lighting switch AUTO OFF β†’ ON 9 - 16 V β†’ less than 1 V
(i81) No. 21 - - -
(i81) No. 22 ←→ Chassis ground Door lock status switch driver's seat Driver's door unlock β†’ lock 9 - 16 V β†’ less than 1 V
(i81) No. 23 ←→ Chassis ground Impact sensor Impact sensor, impact not applied β†’ impact applied Less than 1 V β†’ 9 - 16 V
(i81) No. 24 - - -
(i81) No. 25 - - -
(i81) No. 26 - - -
(i81) No. 27 - - -
(i81) No. 28 - - -
(i81) No. 29 - - -
(i81) No. 30 ←→ Chassis ground P-CR OFF switch Pre-collision brake OFF switch, OFF β†’ ON (when pressed) 9 - 16 V β†’ less than 1 V
(i81) No. 31 - - -
(i81) No. 32 - - -
(B280) No. 1 ←→ Chassis ground Front wiper RTN Front wiper stop position β†’ in operation Less than 1 V β†’ 9 - 16 V
(B280) No. 2 ←→ Chassis ground GND Always Less than 1 Ξ©
(B280) No. 3 ←→ Chassis ground Turn output (left front) Left front turn signal OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(B280) No. 4 ←→ Chassis ground BAT (shift lock, key lock, turn) Always 9 - 16 V
(B280) No. 5 ←→ Chassis ground Key lock solenoid (CVT model without keyless access with push button start system)
  • Ignition key inserted
  • Shift lever, P range β†’ other than P range
 Less than 1 V β†’ 9 - 16 V
(B280) No. 6 - - -
(B280) No. 7 ←→ Chassis ground BAT (control) Always 9 - 16 V
(B280) No. 8 ←→ Chassis ground Turn output (right front) Right front turn signal OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(B281) No. 1 - - -
(B281) No. 2 - - -
(B281) No. 3 ←→ Chassis ground Lighting Hi relay output (left) Dimmer switch Pass OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(B281) No. 4 - - -
(B281) No. 5 ←→ Chassis ground - - -
(B281) No. 6 ←→ Chassis ground DRL cancel During DRL on, dimmer switch Pass OFF β†’ ON 9 - 16 V β†’ less than 1 V
(B281) No. 7 ←→ Chassis ground Lighting 1 relay output Lighting switch 1 OFF β†’ ON 9 - 16 V β†’ less than 1 V
(B281) No. 8 ←→ Chassis ground Rear wiper RTN Rear wiper stop position β†’ in operation Less than 1 V β†’ 9 - 16 V
(B281) No. 9 ←→ Chassis ground Lighting Hi relay output (right) Dimmer switch Pass OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(B281) No. 10 ←→ Chassis ground Answer-back buzzer Answer-back buzzer OFF β†’ ON Less than 1 V β†’ 9 - 16 V
(B281) No. 11 - - -
(B281) No. 12 ←→ Chassis ground Stop light switch Brake pedal, not depressed β†’ depressed Less than 1 V β†’ 9 - 16 V
(B281) No. 13 ←→ Chassis ground MT reverse switch MT shift lever, other than reverse β†’ reverse Less than 1 V β†’ 9 - 16 V
(B281) No. 14 ←→ Chassis ground EGI immobilizer communication Always 1 MO or more
(B281) No. 15 Body system CAN (L) - Communication line
(B281) No. 16 - - -
(B281) No. 17 - - -
(B281) No. 18 ←→ Chassis ground Wiper deicer relay output Rear window defogger switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(B281) No. 19 - - -
(B281) No. 20 ←→ Chassis ground Security output horn Security horn, not operating β†’ operating 9 - 16 V β†’ less than 1 V
(B281) No. 21 ←→ Chassis ground Rear defogger relay output Rear window defogger switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(B281) No. 22 - - -
(B281) No. 23 ←→ Chassis ground Lighting Lo relay output (control) Lighting switch 2 OFF β†’ ON 9 - 16 V β†’ less than 1 V
(B281) No. 24 ←→ Chassis ground Rear wiper ON Rear wiper switch, not operating β†’ operating Less than 1 V β†’ 9 - 16 V
(B281) No. 25 ←→ Chassis ground Front fog light output Front fog light switch OFF β†’ ON 9 - 16 V β†’ less than 1 V
(B281) No. 26 ←→ Chassis ground Power supply for lighting relay (control) ACC OFF β†’ ON (with keyless access with push button start system), or ignition key not inserted β†’ inserted (without keyless access with push button start system) Less than 1 V β†’ 9 - 16 V
(B281) No. 27 - - -
(B281) No. 28 - - -
(B281) No. 29 - - -
(B281) No. 30 - - -
(B281) No. 31 Body system CAN (H) - Communication line
(B281) No. 32 ←→ Chassis ground BAT (backup) Always 9 - 16 V
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