Lexus IS250 · Service Manual BODY ELECTRICAL

Power Source Circuit

Circuit diagnosis

DESCRIPTION

Certification ECU provides power for the door control receiver operation.

WIRING DIAGRAM

B125087E01

INSPECTION PROCEDURE


1. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - DOOR CONTROL RECEIVER)

  1. B125084E03
    Disconnect the P33 certification ECU connector and P31 door control receiver connector.

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

    Standard:
    Symbol
    (Tester Connection)
    Condition
    Specified Condition
    RC0 (P33-29) - +5 (P31-2)
    Always
    Below 1 Ω
    +B1 (P33-1) - Body ground
    Always
    10 to 14 V
    RC0 (P33-29) - Body ground
    Always
    10 kΩ or higher
    E (P33-17) - Body ground
    Always
    Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2. INSPECT CERTIFICATION ECU

  1. B125085E03
    Reconnect the P33 connector.

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

    Standard voltage:
    Symbol
    (Tester Connection)
    Condition
    Specified Condition
    RC0 (P33-29) - E (P33-17)
    Engine switch OFF, all doors closed and transmitter switch not pressed
    Below 1 V
    Engine switch OFF, all doors closed and transmitter switch pressed
    4.6 to 5.4 V
    +B1 (P33-1) - E
    Always
    10 to 14 V



NG
REPLACE CERTIFICATION ECU
OK

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE


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