SECURITY LIGHT: 11, DTC B1681/P1260

BHE090201077W06

SECURITY LIGHT: 11

No detected communication with the coil

DTC: B1681/P1260

DETECTION CONDITION

• No detected communication with the coil

POSSIBLE CAUSE

• Coil malfunction
• Keyless unit malfunction
• Malfunction in the related wiring harnesses

Diagnostic Procedure

STEP

INSPECTION

ACTION

1
INSPECT COIL POWER SUPPLY SYSTEM
• Disconnect the coil connector.
• Turn the ignition switch to the ON position.
• Measure the voltage at coil connector terminal D.
– Is the voltage 8 V or more?
Yes
Go to the next step.
No
Repair the wiring harness.
2
INSPECT WIRING HARNESS BETWEEN COIL AND GROUND
• Turn the ignition switch to the LOCK position.
• Inspect the wiring harness between coil connector terminal C and ground for the following:
– Short to power supply
– Open circuit
• Is the wiring harness normal?
Yes
Go to the next step.
No
Repair the wiring harness.
3
INSPECT COIL INPUT SIGNAL CIRCUIT
• Connect the coil connector.
• Turn the ignition switch to the ON position.
• Measure the voltage at coil connector terminal B.
– Is the voltage 8 V or more?
Yes
Go to Step 7.
No
Go to the next step.
4
INSPECT COIL INPUT SIGNAL CIRCUIT
• Turn the ignition switch to the LOCK position.
• Disconnect the keyless unit connector.
• Turn the ignition switch to the ON position.
• Measure the voltage at keyless unit connector terminal 3E.
– Is the voltage 8 V or more?
Yes
Replace the keyless unit and perform procedures for when replacing the keyless unit only.
No
Go to the next step.
5
INSPECT COMMUNICATION CIRCUIT (INPUT) FOR CONTINUITY
• Turn the ignition switch to the LOCK position.
• Is there continuity between coil connector terminal B and keyless unit connector terminal 3E?
Yes
Go to the next step.
No
Repair the wiring harness.
6
INSPECT COIL INPUT SIGNAL CIRCUIT
• Measure the resistance between coil connector terminal B and ground.
– Is the resistance 10 kilohms or more?
Yes
Replace the coil.
No
Repair the wiring harness.
7
INSPECT COIL OUTPUT SIGNAL CIRCUIT
• Connect the coil connector and the keyless unit connector.
• Turn the ignition switch to the ON position.
• Measure the voltage at coil connector terminal A.
– Is the voltage 8 V or more?
Yes
Replace the coil.
No
Go to the next step.
8
INSPECT COIL OUTPUT SIGNAL CIRCUIT
• Turn the ignition switch to the LOCK position.
• Disconnect the coil connector.
• Turn the ignition switch to the ON position.
• Measure the voltage at coil connector terminal A.
– Is the voltage 8 V or more?
Yes
Replace the coil.
No
Go to the next step.
9
INSPECT COMMUNICATION CIRCUIT (OUTPUT) FOR CONTINUITY
• Turn the ignition switch to the LOCK position.
• Disconnect the keyless unit connector.
• Is there continuity between coil connector terminal A and keyless unit connector terminal 3F?
Yes
Repair the wiring harness.
No
Go to the next step.
10
INSPECT COIL OUTPUT SIGNAL CIRCUIT
• Measure the resistance between keyless unit connector terminal 3F and ground.
– Is the resistance 10 kilohms or more?
Yes
Replace the keyless unit and perform procedures for when replacing the keyless unit only.
No
Repair the wiring harness.