LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2009 >> Prius Base >> Repair and Diagnosis >> Brakes >> Traction Control >> Brake Control >> Electronically Controlled Brake System >> Terminals Of Ecu
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Terminals Of Ecu

  1. CHECK BATTERY VOLTAGE 
    1. Measure the battery voltage.

      Standard voltage: 10 to 14 V 

  2. CHECK SKID CONTROL ECU 
    1. Measure the voltage and resistance between each terminal or between each terminal and the body ground.
    2. Connect the Teachstream to the DLC3, and check the communication condition with the skid control ECU.
    3. Using an oscilloscope, check that the pulse generates between each terminal or between each terminal and the body ground.
      NOTE:
      • Each inspection should be performed from the back of the connector with the connector connected to the skid control ECU.
      • The voltage between the terminals of the brake actuator assembly may become 0 V due to the fail-safe function when the brake control warning light comes on (malfunctioning).
        Fig 1: Identifying ECU Connector Terminals
        G05189207Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      Inspect the ECU from the wire harness side while the connector is connected.

      WIRE HARNESS SPECIFICATION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      R1+(S7-2) - GND(S7-1) P - W Main relay power 1 Push power switch ON (READY) 9.1 to 13.6 V
      BS1 (S7-3) - GND(S7-1) B - W Battery source 1 Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      8.8 to 14 V
      SMC1 (S7-4) - GND (S7-1) Y - W Master cut solenoid 1 output Push power switch ON (READY) Brake pedal depressed approx. 1.5 sec. after pushing power switch ON (READY) Below 1.5 V
      +BCTY (S7-5) - GND (S7-1) V - W Courtesy power input Driver door open → close Approx. 5 sec. 8 to 16 V → Below 1 V
      SLAFR- (S7-6) - GND (S7-1) W - W FR solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      SLAFR+ (S7-7) - GND (S7-1) R - W FR solenoid (+) output Push power switch ON (READY) Brake pedal depressed approx. 1.5 sec. after pushing power switch ON (READY) Pulse generation (see waveform 1)
      E(S7-8) - GND(S7-1) L - W Pressure sensor ground Push power switch OFF Below 1 Ω
      VCM1 (S7-9) - GND (S7-1) P - W Pressure sensor power Push power switch ON (READY) 4.75 to 5.25 V
      MR1+(S7-11) - GND(S7-1) GR - W Motor relay power 1 Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      8.8 to 14 V
      SR1 (S7-12) - GND(S7-1) L-W Main relay output 1 Push power switch ON (READY)
      Approx. 1.5 sec. or more after pushing power switch ON (READY)
      Below 1 V
      SCSS(S7-13) - GND(S7-D BR - W Stroke simulator cut solenoid output Push power switch ON (READY)
      Brake pedal depressed
      Below 1.5 V
      SLARL+(S7-15) - GND (S7-1) L - W RL solenoid (+) output Push power switch ON (READY)
      Brake pedal depressed approx. 1.5 sec. after pushing power switch ON (READY)
      Pulse generation (see waveform 1)
      SLRRL+(S7-16) - GND (S7-1) W - W RL solenoid (+) output Push power switch ON (READY)
      Brake pedal depressed approx. 1.5 sec. after pushing power switch ON (READY)
      Pulse generation (see waveform 1)
      SLRFR+(S7-17) - GND (S7-1) Y - W FR solenoid (+) output Push power switch ON (READY)
      After approx. 1.5 sec, brake pedal depressed → released
      Pulse generation (see waveform 2)
      PRL(S7-18) - GND(S7-1) G - W RL pressure sensor input Push power switch ON (READY)
      Brake pedal released
      0.3 to 0.8 V
      SG1 (S7-20) - GND(S7-1) BR - W Pressure sensor shield ground 1 Push power switch OFF Below 1 Ω
      PACC(S7-21) - GND (S7-1) W - W Accumulator pressure sensor input Push power switch ON (READY)
      After pump motor operates and stops by pedal operation
      3.3 to 4.7 V
      FR-(S7-22) - GND(S7-1) L - W FR sensor (-) input Push power switch OFF Below 1 Ω
      PFR(S7-23) - GND(S7-1) Y - W FR pressure sensor input Push power switch ON (READY)
      Brake pedal released
      0.3 to 0.8 V
      MR1 (S7-25) - GND(S7-1) L - W Motor relay output 1 Push power switch ON (READY)
      Pump motor is operating
      Below 1.5 V
      SLRRL- (S7-26) - GND (S7-1) P - W RL solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      SLARL- (S7-27) - GND (S7-1) LG - W RL solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      MTT(S7-29) - GND(S7-1) R - W Motor test input Push power switch ON (READY)
      Pump motor is operating
      3.5 V or higher
      PMC1 (S7-30) - GND (S7-1) R - W Master pressure sensor input 1 Push power switch ON (READY)
      Brake pedal released
      0.3 to 0.8 V
      PCK1 (S7-31) - GND(S7-1) B - W Pressure sensor check output 1 Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      4.75 to 5.25 V
      FR+(S7-32) - GND(S7-1) P - W FR sensor (+) input Vehicle speed input Pulse generation (see waveform 3)
      SLRFR - (S7-34) - GND (S7-1) B - W FR solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      +BI1 (S8-3) - GND(S8-1, 2) B - W Main relay power input 1 Push power switch OFF 10 to 14 V
      +BO1(S8-5) - GND(S8-1, 2) Y - W Main relay power output 1 Push power switch ON (IG) 8.8 to 14 V
      IG1 (S8-7) - GND(S8-1, 2) B - W IG1 power Push power switch ON (IG) 10 to 14 V
      RSS(S8-10) - GND(S8-1, 2) BR - W Speed sensor shield ground Push power switch OFF Below 1 Ω
      BZ(S8-12) - GND(S8-1, 2) BR - W Warning buzzer output Push power switch ON (READY)
      Buzzer is operating
      Below 1 V
      STP(S8-14) - GND(S8-1, 2) R - W Stop light switch signal input Push power switch ON (READY)
      Brake pedal depressed → released
      8 to 14 V → Below 1 V
      CAN-L(S8-18) - GND(S8-1,2) W-W. CAN communication (Send and receive-) Check DTC using Techstream CAN communication's DTC is not output
      CAN-H(S8-19) - GND (S.8-1,2) B - W CAN communication (Send and receive+) Check DTC using Techstream CAN communication's DTC is not output
      FAIL (S8-20) - GND (S8-1, 2) P - W Capacitor communication (Receive) Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Pulse generation (See waveform 5)
      SP1 (S8-22) - GND(S8-1, 2) V - W Speed meter output Vehicle speed input Pulse generation (See waveform 4)
      RL-(S8-27) - GND(S8-1, 2) B - W RL sensor (-) input Push power switch OFF Below 1 Ω
      D/G(S8-28) - GND(S8-1, 2) W - W Diagnosis output Push power switch ON (READY) 9.1 to 13.6 V
      ENA(S8-30) - GND(S8-1, 2) B - W Capacitor communication (Send) Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Pulse generation (See waveform 6)
      TS(S8-32) - GND(S8-1, 2) L - W Sensor diagnosis check input Push power switch ON (READY) Below 1.5 V → 9.1 to 13,6 V
      VBZ(S8-33) - GND(S8-1, 2) B - W Warning buzzer power Push power switch ON (READY) 9.1 to 13.6 V
      RL+(S8-35) - GND(S8-1, 2) W - W RL sensor (+) input Vehicle speed input Pulse generation (See waveform 3)
      +BO2(S9-4) - GND(S9-1, 2) W - W-B Main relay power output 2 Push power switch ON (READY) 8.8 to 14 V
      +BI2(S9-5) - GND(S9-1, 2) R - W-B Main relay power input 2 Push power switch OFF 10 to 14 V
      VCSK(S9-6) - GND(S9-1, 2) B - W-B Stroke sensor power Push power switch ON (READY) 3.75 to 4.95 V
      SSK(S9-7) - GND(S9-1, 2) Shielded - W-B Stroke sensor shield ground Push power switch OFF Below 1 Ω
      SKG(S9-8) - GND(S9-1, 2) W - W-B Stroke sensor ground Push power switch OFF Below 1 Ω
      PKB(S9-14) - GND(S9-1, 2) R - W-B Parking brake signal input Parking brake applied → released Below 1.5 V → 9.1 to 13.6 V
      SKS1 (S9-21) - GND(S9-1,2) R-W-B Stroke sensor signal input 1 Push power switch ON (READY)
      Brake pedal released
      0.46 to 1.35 V
      SKS2 (S9-22) - GND (S9-1.2) G-W-B Stroke sensor signal input 2 Push power switch ON (READY)
      Brake pedal released
      2.56 to 4.35 V
      RR-(S9-23) - GND(S9-1, 2) B-W-B RR sensor (-) input Push power switch OFF Below 1 Ω
      RR+(S9-31) - GND(S9-1, 2) W - W-B RR sensor (+) input Vehicle speed input Pulse generation (See waveform 3)
      SLAFL+(S10-1) - GND (S10-4) P - W-B FL solenoid (+) output Push power switch ON (READY) Brake pedal depressed approx. 1.5 sec. alter pushing power switch ON (READY) Pulse generation (See waveform 1)
      SLAFL-(S10-2) - GND (S10-4) O - W-B FL solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      SMC2(S10-3) - GND (S10-4) LG - W-B Master cut solenoid 2 output Push power switch ON (READY)
      Brake pedal depressed approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      IG2(S10-5) - GND(S10-4) 0-W-B IG2 power Push power switch ON (READY) 10 to 14 V
      LBL(S10-6) - GND(S10-4) P - W-B Brake fluid level switch input Reservoir level switch OFF → ON 4 to 4.65 V-> Below 1.5 V
      BS2(S10-7) - GND(S10-4) P - W-B Battery source 2 Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      8.8 to 14 V
      SLRFL+(S10-8) - GND (S10-4) Y - W-B FL solenoid (+) output Push power switch ON (READY) After approx. 1.5 sec, brake pedal depressed → released Pulse generation (See waveform 2)
      SLARR- (S10-9) - GND (S10-4) P - W-B RR solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      SG2(S10-12) - GND (S10-4) Shielded - W-B Pressure sensor shield ground 2 Push power switch OFF Below 1 Ω
      FSS(S10-13) - GND (S10-4) BR - W-B Speed sensor shield ground Push power switch OFF Below 1 Ω
      VCM2(S10-14) - GND (S10-4) B-W-B Pressure sensor power 2 Push power switch ON (READY) 4.75 to 5.25 V
      SR2(S10-15) - GND (S10-4) V-W-B Main relay output 2 Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1 V
      R2+(S10-17) - GND(S10-4) Y - W-B Main relay power 2 Push power switch ON (READY) 9.1 to 13.6 V
      SLRRR-(S10-18) - GND (S10-4) BR - W-B RR solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      SLARR+(S10-19) - GND (S10-4) V - W-B RR solenoid (+) output Push power switch ON (READY)
      Brake pedal depressed approx. 1.5 sec. after pushing power switch ON (READY)
      Pulse generation (See waveform 1)
      SLRRR+(S10-20) - GND (S10-4) R - W-B RR solenoid (+) output Push power switch ON (READY)
      Brake pedal depressed approx. 1.5 sec. after pushing power switch ON (READY)
      Pulse generation (See waveform 1)
      PCK2(S10-21) - GND (S10-4) L - W-B Pressure sensor check output 2 Push power switch ON (READY) 4.75 to 5.25 V
      FL-(S10-22) - GND(S10-4) G - W-B FL sensor (-) input Push power switch OFF Below 1 Ω
      PFL(S10-23) - GND(S10-4) R - W-B FL pressure sensor input Push power switch ON (READY)
      Brake pedal released
      0.3 to 0.8 V
      MR2+(S10-25) - GND (S10-4) R-W-B Motor relay power 2 Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      8.8 to Below 14 V
      SLRFL-(S10-26) - GND (S10-4) L-W-B FL solenoid (-) output Push power switch ON (READY)
      Approx. 1.5 sec. after pushing power switch ON (READY)
      Below 1.5 V
      PMC2(S10-27) - GND (S10-4) W - W-B Master pressure sensor input 2 Push power switch ON (READY)
      Brake pedal released
      0.3 to 0.8 V
      FL+(S10-28) - GND(S10-4) R - W-B FL sensor (+) input Vehicle speed input Pulse generation (See waveform 3)
      E2(S10-29) - GND(S10-4) G - W-B Pressure sensor ground 2 Push power switch OFF Below 1 Ω
      MR2(S10-30) - GND (S10-4) G - W-B Motor relay output 2 Push power switch ON (READY)
      Pump motor is operating
      Below 1.5 V
      PRR(S10-31) - GND (S10-4) Y-W-B RR pressure sensor input Push power switch ON (READY)
      Brake pedal released
      0.3 to 0.8 V
    4. Using an oscilloscope, check the waveform 1.

      Waveform 1 (Reference) 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) SLAFR+ (S7-7) - GND (S7-1)
      SLARL+ (S7-15) - GND (S7-1)
      SLRRL+ (S7-16) - GND (S7-1)
      SLAFL+ (S10-2) - GND (S10-4)
      SLARR+ (S10-19) - GND (S10-4)
      SLRRR+ (S10-20) - GND (S10-4)
      Tool Setting 5V/DIV.,200msec./DIV.
      Condition Brake pedal depressed
      Fig 2: Identifying Waveform 1
      G05189208Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: Normal waveform is output only when BS 1 and 2 voltages are normal (10 to 14 V).
    5. Using an oscilloscope, check the waveform 2.

      Waveform 2 (Reference) 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) SLRFR+ (S7-17) - GND (S7-1)
      SLRFL+ (S10-8) - GND (S10-4)
      Tool Setting 5V/DIV.,200msec./DIV.
      Condition Brake pedal depressed → released
      NOTE: Normal waveform is output only when BS 1 and 2 voltages are normal (10 to 14 V).
      Fig 3: Identifying Waveform 2
      G05189208Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Using an oscilloscope, check the waveform 3.

      Waveform 3 (Reference) 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) FR+(S7-32) - GND(S7-1)
      RL+(S8-35) - GND(S8-1,2)
      RR+(S9-31) - GND(S9-1,2)
      FL+(S10-28) - GND(S10-4)
      Tool Setting 1 V/DIV., 200 msec./DIV.
      Condition While driving at approximately 18 mph (30 km/h)
      Fig 4: Identifying Waveform 3
      G05010960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: As the vehicle speed (tire rotating speed) becomes faster, the cycle becomes shorter and the output voltage becomes larger.
    7. Using an oscilloscope, check the waveform 4.

      Waveform 4 (Reference) 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) SP1 (S8-22) - GND(S8-1,2)
      Tool Setting 5 V/DIV., 50 msec./DIV.
      Condition While driving at approximately 12 mph (20 km/h)
      Fig 5: Identifying Waveform 3
      G05010961Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      NOTE: As the vehicle speed (tire rotating speed) becomes faster, the cycle becomes shorter.
    8. Using an oscilloscope, check the waveform 5.

      Waveform 5 (Reference) 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) FAIL(S8-20) - GND(S8-1,2)
      Tool Setting 5 V/DIV., 200 msec./DIV.
      Condition Power switch ON (READY)
      Fig 6: Identifying Waveform 5
      G05010962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    9. Using an oscilloscope, check the waveform 6.

      Waveform 6 (Reference) 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) ENA (S8-30) - GND (S8-T, 2)
      Tool Setting 5 V/DIV., 100 msec./DIV.
      Condition Power switch ON (READY)
      Fig 7: Identifying Waveform 6
      G05010962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002