2008 Lexus ES 350FACTORY OEM SERVICE PROCEDURE

Terminals Of Ecu

Fig 1: Identifying Terminals Of ECU Connector
G05247890Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
ECU - TERMINALS REFERENCE CHART

Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
+B (A9-2) - GND (A9-12) B - GR +B (BATT) power supply Always 10 to 14 V
IG2 (A9-10) - GND (A9-12) P - GR Ignition power supply Engine switch on (IG) 10 to 14 V
ACT+ (A9-1) - ACT- (A9-3) R - L E-ACM actuator Idling Pulse generation (see  1waveform 1)
VGS (A9-24) - GGND (A9-26) B - R Acceleration sensor power supply Engine switch on (IG) 4.5 to 5.2 V
GL1 (A9-19) - GGND (A9-26) W - R Acceleration sensor output voltage Engine switch on (IG) 0.11 to 4 46 V
TACH (A9-16) - GND (A9-12) B - GR Engine speed Idling Pulse generation (see  2waveform 2)
CANH (A9-14) - GND (A9-12) G - GR MPX line Always Pulse generation (see  3waveform 3)
CANL (A9-13) - GND (A9-12) R - GR MPX line Always Pulse generation (see  4waveform 4)
  1. Waveform 1 
    1. Active control engine mount actuator signal
      WAVEFORM REFERENCE

      Symbols (Terminal No) Between ACT+ and ACT-
      Tool Setting 5V/DIV, 10 ms/DIV
      Condition Idling with warm engine

      HINT:

      • The duty ratio varies depending on the active control engine mount actuator operation.
      • Do not disconnect the active control engine mount ECU connector.
        Fig 2: Identifying Waveform 1
        G05247891Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Waveform 2 
    1. Engine speed signal
      WAVEFORM REFERENCE

      Symbols (Terminal No.) Between TACH and GND
      Tool Setting 5 V/DIV., 10 ms/DIV
      Condition Idling

      HINT:

      The wavelength becomes shorter as the engine rpm increases.

      Fig 3: Identifying Waveform 2
      G04973001Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Waveform 3 
    1. CAN communication signal
      WAVEFORM REFERENCE

      Symbols (Terminal No.) Between CANH and GND
      Tool Setting 1 V/DIV, 10 μs/DIV
      Condition Stop engine and engine switch on (IG)

      HINT:

      The waveform varies depending on the CAN communication signal.

      Fig 4: Identifying Waveform 3
      G04828030Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. Waveform 4 
    1. CAN communication signal
      WAVEFORM REFERENCE

      Symbols (Terminal No.) Between CANL and GND
      Tool Setting 1 V/DIV., 10 μs/DIV.
      Condition Stop engine and engine switch on (IG)

      HINT:

      The waveform varies depending on the CAN communication signal.

      Fig 5: Identifying Waveform 4
      G04828031Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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