Unlock Warning Switch Circuit

DOOR LOCK: KEY REMINDER WARNING SYSTEM: Unlock Warning Switch Circuit

Unlock Warning Switch Circuit

DESCRIPTION

The unlock warning switch detects if the key is in the ignition key cylinder.
The unlock warning switch turns on when the key is inserted into the ignition key cylinder and turns off when the key is removed from the cylinder.
The body ECU is connected to the unlock warning switch via terminal KSW and key detection status signals are input to the ECU.
The body ECU applies voltage to the unlock warning switch via terminal KSW. When the unlock warning switch is on (there is continuity between the switch terminals), a signal indicating that the key is in the ignition key cylinder is input to the body ECU. When the switch is off (there is no continuity between the switch terminals), a signal indicating that the key is not in the cylinder is input.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ VALUE USING INTELLIGENT TESTER
(a) Connect the intelligent tester (with CAN VIM) to the DLC3.
(b) Turn the ignition switch to the ON position and turn the intelligent tester main switch on.
(c) Select KEY UNLK WRN SW in the DATA LIST and read the value displayed on the tester.

BODY:





OK:
ON (Key is in ignition key cylinder) appears on the screen.
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG -- Continue to next step.
2. INSPECT UNLOCK WARNING SWITCH ASSEMBLY





(a) Remove the unlock warning switch assembly.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPLACE UNLOCK WARNING SWITCH ASSEMBLY
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - BODY ECU)





(a) Disconnect the K4 switch and B4 ECU connectors.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. CHECK HARNESS AND CONNECTOR (UNLOCK WARNING SWITCH - BODY GROUND)





(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE