Unlock Warning Switch Circuit
Circuit diagnosis
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
| 1. READ VALUE OF DATA LIST (UNLOCK WARNING SWITCH) |
Check the DATA LIST to ensure proper operation of the door unlock detection switch.
Body ECU: Item
Measurement Item /
Display (Range)
Normal Condition
Diagnostic Note
Key Unlock Warning SW
Unlock warning switch signal
/ON or OFF
ON: Key is in ignition key cylinder
OFF: No key is in ignition key cylinder
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- OK:
- The display is as specified in the normal condition.
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| OK | ||
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| 2. INSPECT UNLOCK WARNING SWITCH ASSEMBLY |
Remove the unlock warning switch assembly.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection
Condition
Specified Condition
1 - 2
Free
10 kΩ or higher
1 - 2
Pushed
Below 1 Ω
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| OK | |
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| 3. CHECK WIRE HARNESS (UNLOCK WARNING SWITCH - INSTRUMENT PANEL J/B (BODY ECU)) |
Disconnect the unlock warning switch assembly connector.
Disconnect the instrument panel J/B connector.
Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection
Condition
Specified Condition
K6-2 - B6-21 (KSW)
Always
Below 1 Ω
K6-1 - Body ground
Always
Below 1 Ω
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| OK | ||
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