Lexus IS250 · Service Manual ENGINE

B2275

Diagnostic trouble codes

DESCRIPTION

This DTC is output when there is an open, short, or any other problem in the engine start request output circuit inside the power source control ECU or in the external circuit.

HINT:
When the power source control ECU is replaced with a new one and the negative (-) battery terminal is connected, the power source mode becomes the IG-ON mode. When the battery is removed and reinstalled, the power source mode that was selected when the battery was removed is restored.

DTC No.
 DTC Detection Condition
 Trouble Area
B2275
 ST output circuit (engine starting request signal circuit) inside power source control ECU or other related circuit is malfunctioning
  1. AM2 fuse
  2. ECM
  3. Steering lock ECU
  4. Power source control ECU
  5. Wire harness or connector

WIRING DIAGRAM

B112580E02

INSPECTION PROCEDURE


1. CHECK FOR DTCS

  1. Delete the DTC (Click here).

    HINT:
    After all DTCs are cleared, turn the engine switch on (IG). After 25 seconds have elapsed, check if the trouble occurs again.

  1. Check for DTCs again.

    OK:
    DTC B2285 is not output.

    HINT:
    If DTC B2285 is output, perform troubleshooting for DTC B2285 first (Click here).



 NG
DTC CHART
OK


2. INSPECT FUSE (AM2)

  1. Remove the AM2 fuse from the cowl side J/B RH.

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω



 NG
REPLACE FUSE
OK


3. CHECK CONNECTORS

  1. Check that the connectors are securely connected and the terminals are not deformed or loose.

    OK:
    The connectors are securely connected and the terminals are not deformed or loose.



 NG
REPAIR OR REPLACE CONNECTORS
OK


4. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BATTERY AND BODY GROUND)

  1. B128304E25
    Disconnect the J55 ECU connector.

  1. Measure the voltage according to the value(s) in the table below.

    Standard voltage:
    Tester Connection (Symbols)
    		 Condition
    		 Specified Condition
    J55-33 (AM1) - Body ground
    		 Always
    		 10 to 14 V
    J55-12 (AM2) - Body ground
    		 Always
    		 10 to 14 V

  1. Measure the resistance according to the value(s) in the table below.

    Standard resistance:
    Tester Connection (Symbols)
    		 Condition
    		 Specified Condition
    J55-6 (GND2) - Body ground
    		 Always
    		 Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - ECM)

  1. A109242E13
    Disconnect the A5 ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard resistance:
    Tester Connection (Symbols)
    		 Condition
    		 Specified Condition
    J55-39 (STSW) - A5-19 (STSW)
    		 Always
    		 Below 1 Ω
    J55-39 (STSW) or A5-19 (STSW) - Body ground
    		 Always
    		 10 kΩ or higher

  1. B128304E01
    Reconnect the A5 ECM connector.

  1. Measure the voltage according to the value(s) in the table below.

    Standard voltage:
    Tester Connection (Symbols)
    		 Condition
    		 Specified Condition
    J55-39 (STSW) - Body ground
    		 Always
    		 Below 1 V



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


6. CHECK WIRE HARNESS (STEERING LOCK ECU - POWER SOURCE CONTROL ECU AND BODY GROUND)

  1. A118197E02
    Disconnect the J29 ECU connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard resistance:
    Tester Connection (Symbols)
    		 Condition
    		 Specified Condition
    J29-1 (GND) - Body ground
    		 Always
    		 Below 1 Ω
    J29-4 (SLP1) - J55-26 (SLP)
    		 Always
    		 Below 1 Ω
    J29-4 (SLP1) or J55-26 (SLP) - Body ground
    		 Always
    		 10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


7. INSPECT POWER SOURCE CONTROL ECU

  1. B112480E16
    Reconnect the J55 ECU connector.

  1. A130277E02
    Connect the oscilloscope to the power source control ECU terminals specified in the table below and check the waveform.
    Item
    		 Contents
    Terminal (Symbols)
    		 J55-26 (SLP) - Body ground
    Equipment Setting
    		 2 V/DIV, 100 ms/DIV
    Condition
    		 Engine switch on (IG)

    OK:
    The waveform appears as shown in the illustration.

    HINT:
    The waveform varies depending on the contents of communication.



 NG
REPLACE POWER SOURCE CONTROL ECU
OK


8. INSPECT STEERING LOCK ECU

  1. B112480E16
    Reconnect the J29 ECU connector.

  1. A130277E01
    Connect the oscilloscope to the power source control ECU terminals specified in the table below and check the waveform.
    Item
    		 Contents
    Terminal (Symbols)
    		 J55-26 (SLP) - Body ground
    Equipment Setting
    		 2 V/DIV, 100 ms/DIV
    Condition
    		 Steering is LOCK / UNLOCK

    OK:
    The waveform appears as shown in the illustration.

    HINT:
    The waveform varies depending on the contents of communication.



 NG
REPLACE STEERING LOCK ECU
OK


9. INSPECT POWER SOURCE CONTROL ECU

  1. B112480E14
    Disconnect the A5 ECM connector.

  1. Measure the voltage according to the value(s) in the table below.

    Standard voltage:
    Tester Connection (Symbols)
    		 Condition
    		 Specified Condition
    J55-39 (STSW) - Body ground
    		 Brake pedal (A/T) or clutch pedal (M/T) depressed, Engine switch off
    		 Below 1 V
    Brake pedal (A/T) or clutch pedal (M/T) depressed, Engine switch on (IG)
    		 8 to 14 V



NG
REPLACE POWER SOURCE CONTROL ECU
OK

REPLACE ECM


← B2274B2276 →