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Terminals Of Ecu

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

      Standard Voltage: 

      11 to 14 V 

  2. SKID CONTROL ECU INSPECTION 
    1. Measure the voltage between each terminal or between each terminal and the body ground.
    2. Connect the Techstream to the DLC3, and check the communication condition with the skid control ECU
    3. Using an oscilloscope, check the pulse generated between each terminal or between each terminal and body ground
      NOTE: Inspection should be performed from the back of the connector with the connector connected to the skid control ECU.
      Fig 1: Identifying Skid Control ECU Connector Terminals
      G05752554Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TERMINAL DESCRIPTION

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A35-1 (SFRR) - Body ground GR - Body ground Front decrease solenoid RH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      A35-2 (SRLR) - Body ground R - Body ground Rear decrease solenoid LH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      A35-3 (MR) - Body ground L-B - Body ground ABS motor relay output Engine switch on (IG) 11 to 14 V
      A35-4 (FLO) - Body ground R-L - Body ground Front wheel speed signal LH output While driving Pulse generation (see  dwaveform 1)
      A35-5 (FRO) - Body ground G-W - Body ground Front wheel speed signal RH output While driving Pulse generation (see  dwaveform 1)
      A35-7 (FR-) - Body ground G - Body ground Front wheel speed sensor RH input Vehicle speed (forward or backward) input Pulse generation (see  ewaveform 2)
      A35-8 (FR+) - Body ground L - Body ground Front wheel speed sensor power supply RH output Engine switch on (IG) 11 to 14 V
      A35-9 (FL+) - Body ground P - Body ground Front wheel speed sensor power supply LH output Engine switch on (IG) 11 to 14 V
      A35-10 (FL-) - Body ground L - Body ground Front wheel speed sensor LH input Vehicle speed (forward or backward) input Pulse generation (see  ewaveform 2)
      A35-11 (R+) - Body ground G - Body ground ABS solenoid relay power supply Engine switch on (IG) 11 to 14 V
      A35-12 (SRRR) - Body ground W-L - Body ground Rear decrease solenoid RH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      A35-13 (SFLR) - Body ground W - Body ground Front decrease solenoid RH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      A35-14 (SSEL) - Body ground Y-B - Body ground Solenoid characteristic identification input 1 Engine start Low 0 V (Normal)
      Middle 3 7 to 8 26 V
      High 7 8 to 14 V
      A35-16 (SEL2) - Body ground B-L - Body ground Solenoid characteristic identification input 2 Engine start Low 0 V (Normal)
      Middle 3 7 to 8 26 V
      High 7 8 to 14 V
      A35-18 (FSW+) - Body ground G-B - Body ground Brake pedal load sensing switch input Stop light switch OFF → ON (Brake pedal depressed → released) 950 to 1050 Ω → 203 to 223 →
      A35-20 (STP2) - Body ground R-B - Body ground Stop light control (BRK-LP) relay input Stop light switch ON → OFF (Brake pedal depressed → released) 11 to 14 V → Below 1 5 V
      A35-21 (STPO) - Body ground L - Body ground Stop light control (BRK-LP) relay output Engine switch on (IG) 11 to 14 V
      A35-22 (GND3) - Body ground W-B - Body ground Skid control ECU ground 3 Always Below 1 →
      J77-1 (IG1) - Body ground B - Body ground IG1 power supply Engine switch on (IG) 11 to 14 V
      J77-3 (RL-) - Body ground B - Body ground Rear wheel speed sensor LH input Vehicle speed (forward or backward) input Pulse generation (see  ewaveform 2)
      J77-4 (RL+) - Body ground LG - Body ground Rear wheel speed sensor power supply LH output Engine switch on (IG) 11 to 14 V
      J77-5 (RR+) - Body ground B - Body ground Rear wheel speed sensor power supply RH output Engine switch on (IG) 11 to 14 V
      J77-6 (RR-) - Body ground G - Body ground Rear wheel speed sensor RH input Vehicle speed (forward or backward) input Pulse generation (see  ewaveform 2)
      J77-7 (CSW) - Body ground P - Body ground VSC OFF switch input VSC OFF switch ON → OFF Below 1 Ω → 10 kΩ or higher
      J77-8 (CANH) - Body ground R - Body ground CAN communication line H Engine switch off 54 to 67 Ω
      J77-9 (SP1) - Body ground V - Body ground Speed signal output for combination meter While driving Pulse generation (see  fwaveform 3)
      J77-10 (STP1) - Body ground R - Body ground Stop light switch input Stop light switch ON → OFF (Brake pedal depressed → released) 11 to 14 V → Below 1 5 V
      J77-11 (BZ) - Body ground L - Body ground Skid control buzzer output Engine switch on (IG), buzzer sound → not sound Below 1 V → 11 to 14 V
      J77-12 (D/G) - Body ground R - Body ground Diagnosis tester communication line Engine switch on (IG) 11 to 14 V
      J77-13 (TS) - Body ground SB - Body ground Sensor check activation input Engine switch on (IG), terminals TS and CG of DLC3 connect → disconnect Below 1 5 V → 11 to 14 V
      J77-14 (PKB) - Body ground Y - Body ground Parking brake switch input Engine switch on (IG), parking brake switch ON → OFF Below 1 Ω → 10 kΩ or higher
      J77-15 (WFSE) - Body ground GR - Body ground ECU program rewrite input - -
      J77-16 (CANL) - Body ground W - Body ground CAN communication line L Engine switch off 54 to 67 Ω
      J78-1 (MRF) - Body ground Y - Body ground ABS motor fail safe relay output Approx 1 5 seconds after turning engine switch on (IG) Below 1 V
      J78-2 (SR) - Body ground V - Body ground ABS solenoid relay output Approx 1 5 seconds after turning engine switch on (IG) Below 1 V
      J78-4 (PMC) - Body ground R - Body ground Master cylinder pressure sensor input Engine switch on (IG), brake pedal released 0 3 to 0 8 V
      J78-6 (E2) - Body ground W - Body ground Master cylinder pressure sensor ground Always Below 1 Ω
      J78-7 (RRA+) - Body ground L - Body ground Rear holding solenoid (+) RH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-8 (FLA-) - Body ground W - Body ground Front holding solenoid (-) LH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-9 (RLA+) - Body ground G - Body ground Rear holding solenoid (+) LH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-10 (FRA-) - Body ground GR - Body ground Front holding solenoid (-) RH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-11 (SM2+) - Body ground B - Body ground Master cut linear solenoid 2 (+) output Approx 1 5 seconds after turning engine switch on (IG) Below 1 V
      J78-12 (SM1-) - Body ground R - Body ground Master cut linear solenoid 1 (-) output Approx 1 5 seconds after turning engine switch on (IG) Below 1 V
      J78-13 (AST) - Body ground Y - Body ground Linear solenoid power supply Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-14 (GND2) - Body ground W-B - Body ground Skid control ECU ground 2 Always Below 1 Ω
      J78-15 (MT) - Body ground GR - Body ground ABS motor relay test input Approx 1 5 seconds after turning engine switch on (IG) Below 1 V
      J78-18 (VCM) - Body ground B - Body ground Master cylinder pressure sensor power supply output Engine switch on (IG) 4 5 to 5 5 V
      J78-19 (FSS) - Body ground Shielded - Body ground Master cylinder pressure sensor shielded ground Always Below 1 Ω
      J78-20 (RRA-) - Body ground O - Body ground Rear holding solenoid (-) RH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-21 (FLA+) - Body ground V - Body ground Front holding solenoid (+) LH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-22 (RLA-) - Body ground P - Body ground Rear holding solenoid (-) LH output Approx 1 5 seconds after turning engine switch on (IG) 11 to 14 V
      J78-23 (FRA+) - Body ground LG - Body ground Front holding solenoid (+) RH output Approx 1 5 seconds after turning engine switch on (IG 11 to 14 V
      J78-24 (SM2-) - Body ground BR - Body ground Master cut linear solenoid 2 (-) output Approx 1 5 seconds after turning engine switch on (IG) Below 1 V
      J78-25 (SM1+) - Body ground SB - Body ground Master cut linear solenoid 1 (+) output Approx 1 5 seconds after turning engine switch on (IG) Below 1 V
      J78-26 (GND1) - Body ground W-B - Body ground Skid control ECU ground 1 Always Below 1 Ω
    4. Waveform 1 (Reference) Using an oscilloscope
      WAVEFORM 1 (REFERENCE)

      Item Condition
      Tool setting 5 V/DIV, 5 ms/DIV
      Vehicle condition While driving at approximately 20 km/h (12 mph)

      HINT

      As the vehicle speed (wheel speed) becomes faster, the cycle becomes shorter

      Fig 2: Waveform 1 Graph
      G05319296Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Waveform 2 (Reference). Using an oscilloscope
      WAVEFORM 2 (REFERENCE)

      Item Condition
      Tool setting 0 5 V/DIV, 2 ms /DIV
      Vehicle condition Moving forward or backward

      HINT

      As the vehicle speed (wheel speed) becomes faster, the cycle becomes shorter.

      Fig 3: Waveform 2 Graph
      G05752556Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Waveform 3 (Reference) - Using an oscilloscope
      WAVEFORM 3 (REFERENCE)

      Item Condition
      Tool setting 5 V/DIV, 50 ms/DIV
      Vehicle condition While driving at approximately 20 km/h (12 mph)

      HINT

      As the vehicle speed (wheel speed) becomes faster, the cycle becomes shorter.

      Fig 4: Waveform 3 Graph
      G05752557Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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