Pre-Crash Safety System Diagnosis System

Restraints. Lexus Is250, Is220D. Gse20 Ale20
Pre-Crash Safety. Lexus Is250, Is220D. Gse20 Ale20

  1. CHECK DLC3

  1. FUNCTION OF WARNING INDICATOR AND MESSAGE

Pre-Crash Safety System -- Diagnosis System



CHECK DLC3
Lexus Is250, Is220D. Gse20 Ale20.Pre-Crash Safety.Pre-Crash Safety System.Pre-Crash Safety System Diagnosis System

  1. The seat belt control ECU uses CAN and ISO 15765-4 communication protocol. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format.

    Symbols (Terminals No.)
    		Terminal Description
    		Condition
    		Specified Condition
    SIL (7) - SG (5)
    		Bus "+" line
    		During transmission
    		Pulse generation
    CG (4) - Body ground
    		Chassis ground
    		Always
    		Below 1 Ω
    SG (5) - Body ground
    		Signal ground
    		Always
    		Below 1 Ω
    BAT (16) - Body ground
    		Battery positive
    		Always
    		10 to 14 V
    CANH (6) - CANL
    		HIGH - level CAN bus line
    		Engine switch off
    		54 to 67 Ω
    CANH (6) - Battery positive
    		HIGH - level CAN bus line
    		Engine switch off
    		1 MΩ or higher
    CANH (6) - CG (4)
    		HIGH - level CAN bus line
    		Engine switch off
    		3 MΩ or higher
    CANL (14) - Battery positive
    		LOW - level CAN bus line
    		Engine switch off
    		1 MΩ or higher
    CANL (14) - CG (4)
    		LOW - level CAN bus line
    		Engine switch off
    		3 MΩ or higher
If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector.
HINT:
Connect the cable of the intelligent tester to the DLC3, turn the engine switch on (IG) and attempt to use the tester. If the display indicates that a communication error has occurred, there is a problem either with the vehicle or with the tester.
  1. If the tester is able to communicate when it is connected to another vehicle, inspect the DLC3 of the original vehicle.
  2. If communication is still not possible when the tester is connected to another vehicle, the problem may be in the tester itself. Consult the tester's instruction manual for information on service or repair of the tester.

FUNCTION OF WARNING INDICATOR AND MESSAGE


    Lexus Is250, Is220D. Gse20 Ale20

  1. If the pre-crash safety is not functioning properly, the driver is warned by the master warning indicator and multi-information display warning message on the combination meter.

    Master Warning Indicator
    		Warning Message
    		Detail
    		DTC
    		PCS Warning indicator
    ON
    		CHECK PCS SYSTEM
    		This message appears when the seat belt control ECU detects a system malfunction
    		○
    		ON
    Illuminate
    		PCS NOT AVAILABLE NOW
    		This message appears when the seat belt control ECU is in the fail-safe mode (Click here)
    		-
    		Blinking


  2. Initial check.



      Lexus Is250, Is220D. Gse20 Ale20

    1. The initial check occurs when the engine switch is off for more than 2 seconds, and then turned on (IG). The initial check consists of a pre-crash safety diagnostic check with a duration of approximately 3 seconds.

    2. If a malfunction is detected during the initial check, the multi-information display will output "CHECK PCS SYSTEM " or "PCS NOT AVAILABLE NOW".

  3. Constant check.

    1. The seat belt control ECU and distance control ECU constantly monitor the pre-crash safety for malfunctions after the initial check approximately 3 seconds after turning the engine switch on (IG).

    2. "CHECK PCS SYSTEM" or "PCS NOT AVAILABLE NOW" is displayed on the multi-information display in the combination meter assembly when the constant check detects malfunctions in the pre-crash safety.