2021 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE

Module I/O Signal

Unit body 

G13648960Courtesy of SUBARU OF AMERICA, INC.
  • Power supply and speaker output terminal
    • Model without power amplifier
      Terminal No. Contents Measuring condition Measurement value Note
      (i85) No. 1 FR+ - - -
      (i85) No. 2 FL+ - - -
      (i85) No. 3 ↔ Chassis ground ACC ACC ON 11 - 15 V -
      (i85) No. 4 ↔ Chassis ground +B Always 11 - 15 V -
      (i85) No. 5 FR- - - -
      (i85) No. 6 FL- - - -
      (i85) No. 7 <-<↔Chassis ground GND Always 0 V -
      (i85) No. 8 ANT-ON - - -
      (i85) No. 9 NC - - -
      (i85) No. 10 ILL+ - - -
      (i131) No. 1 RR+ - - -
      (i131) No. 2 RL+ - - -
      (i131) No. 3 RR- - - -
      (i131) No. 4 NC - - -
      (i131) No. 5 ILL- - - -
      (i131) No. 6 RL- - - -
    • Model with power amplifier
      Terminal No. Contents Measuring condition Measurement value Note
      (i35) No. 1 FR+ - - -
      (i35) No. 2 FL+ - - -
      (i35) No. 3 <-<↔ Chassis ground ACC ACC ON 11 - 15 V -
      (i35) No. 4 <-<↔ Chassis ground +B Always 11 - 15 V -
      (i35) No. 5 FR- - - -
      (i35) No. 6 FL- - - -
      (i35) No. 7 <-<↔ Chassis ground GND Always 0 V -
      (i35) No. 8 ANT-ON - - -
      (i35) No. 9 NC - - -
      (i35) No. 10 ILL+ - - -
      (i36) No. 1 NC - - -
      (i36) No. 2 INT+ - - -
      (i36) No. 3 NC - - -
      (i36) No. 4 SLD2 - - -
      (i36) No. 5 ILL- - - -
      (i36) No. 6 INT- - - -
  • Steering switch and AUX input terminal for microphone etc.
    Terminal No. Contents Measuring condition Measurement value Note
    (i87) No. 1 ↔ Chassis ground IGN IGN ON 11 - 15 V -
    (i87) No. 2 REVERSE - - -
    (i87) No. 3 BRIGHT - - -
    (i87) No. 4 VCC - - -
    (i87) No. 5 MIC+ - - -
    (i87) No. 6 DET - - -
    (i87) No. 7 NC- (1)/AMP CAN+ (for AMP communication)(1) - - -
    (i87) No. 8 NC- (1)/AMP CAN- (for AMP communication)(2) - - -
    (i87) No. 9 CAN+ - - -
    (i87) No. 10 CAN- - - -
    (i87) No. 11 AC-UART (+) - - -
    (i87) No. 12 AC-UART(-) - - -
    (i87) No. 13 MIC2+ - - -
    (i87) No. 14 MIC2- - - -
    (i87) No. 15 ↔ Chassis ground PKB At parking ON 1 V or less -
    (i87) No. 16 NC- (1)/MUTE(2) - - -
    (i87) No. 17 ↔ Chassis ground SPEED When the tire is rotating Pulse signal -
    (i87) No. 18 SGND - - -
    (i87) No. 19 MIC- - - -
    (i87) No. 20 TEST - - -
    (i87) No. 21 STEERING SW1+ - - -
    (i87) No. 22 STEERING SW2+ - - -
    (i87) No. 23 STEERING SW GND - - -
    (i87) No. 24 DC MODULE MUTE - - -
    (i87) No. 25 FRONT ON - - -
    (i87) No. 26 R SIG - - -
    (i87) No. 27 R/L SIG - - -
    (i87) No. 28 L SIG - - -
    (1) Model without power amplifier

    (2) Model with power amplifier
  • Rearview camera
    Terminal No. Contents Measuring condition Measurement value Note
    (i146) No. 1 <↔ Chassis ground GND Always 0 V -
    (i146) No. 2 6 V+ - - -
    (i146) No. 3 CA+ - - -
    (i146) No. 4 CA- - - -
    (i146) No. 5 NC - - -

Power amplifier 

G13262729Courtesy of SUBARU OF AMERICA, INC.
Terminal No. Contents Measuring condition Measurement value Note
(R386) No. 1 NC - - -
(R386) No. 2 NC - - -
(R386) No. 3 NC - - -
(R386) No. 4 NC - - -
(R386) No. 5 TX- - - -
(R386) No. 6 TX+ - - -
(R386) No. 7 IL1 + - - -
(R386) No. 8 <↔ Chassis ground ACC ACC ON 11 - 15 V -
(R386) No. 9 NC - - -
(R386) No. 10 NC - - -
(R386) No. 11 NC - - -
(R386) No. 12 <↔ Chassis ground +B A ways 11 - 15 V -
(R386) No. 13 <↔ Chassis ground +B Always 11 - 15 V -
(R386) No. 14 <↔ Chassis ground +B Always 11 - 15 V -
(R386) No. 15 <↔ Chassis ground +B Always 11 - 15 V -
(R386) No. 16 NC - - -
(R386) No. 17 NC - - -
(R386) No. 18 NC - - -
(R386) No. 19 NC - - -
(R386) No. 20 NC - - -
(R386) No. 21 IL- - - -
(R386) No. 22 NC - - -
(R386) No. 23 NC - - -
(R386) No. 24 NC - - -
(R386) No. 25 <↔ Chassis ground GND Always 0 V -
(R386) No. 26 <↔> Chassis ground GND Always 0 V -
(R386) No. 27 <↔ Chassis ground GND Always 0 V -
(R386) No. 28 <↔> Chassis ground GND Always 0 V -
(R316) No. 1 FR+ - - -
(R316) No. 2 TWR+ - - -
(R316) No. 3 RR+ - - -
(R316) No. 4 WF2 - - -
(R316) No. 5 NC - - -
(R316) No. 6 L+ - - -
(R316) No. 7 R+ - - -
(R316) No. 8 NC - - -
(R316) No. 9 NC - - -
(R316) No. 10 NC - - -
(R316) No. 11 NC - - -
(R316) No. 12 WF1 + - - -
(R316) No. 13 RL+ - - -
(R316) No. 14 TWL+ - - -
(R316) No. 15 FL+ - - -
(R316) No. 16 FR- - - -
(R316) No. 17 TWR- - - -
(R316) No. 18 RR- - - -
(R316) No. 19 WF2- - - -
(R316) No. 20 L- - - -
(R316) No. 21 R- - - -
(R316) No. 22 NC - - -
(R316) No. 23 NC - - -
(R316) No. 24 NC - - -
(R316) No. 25 WF1- - - -
(R316) No. 26 RL- - - -
(R316) No. 27 TWL- - - -
(R316) No. 28 FL- - - -
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