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DTC C0040:24 [BODY CONTROL MODULE (BCM)]

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Outline

System malfunction location	Brake switch (No.1 signal) circuit malfunction
Detection condition	•  The body control module (BCM) detects that the brake switch No.1 signal is in the on condition for a continuous 5 times even though brake switch No.2 signal changes.
Fail-safe	•  Determined by brake switch (No.2 signal) with the brake pedal depressed.
Possible cause	Caution •  Inspect the brake switch with it installed to the brake pedal, otherwise the brake switch may not operate normally. If the brake switch is removed from the brake pedal, replace the brake switch with a new one. •  Brake switch (No.1 signal) connector or terminal malfunction •  Brake switch (No.1 signal) malfunction •  Body control module (BCM) connector or terminal malfunction •  Short to power supply in brake switch (No.1 signal) signal circuit •  Body control module (BCM) malfunction

Diagnostic Procedure

Step	Inspection	Results	Action
1	VERIFY BODY CONTROL MODULE (BCM) DTCs AGAIN •  Clear the DTC recorded in the memory. (See CLEARING DTC.) •  Perform the work of depressing the brake pedal for 3 s or more and then releasing it for 5 times or more with the ignition switched ON (engine off or on). •  Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) •  Is the same Pending DTC present?	Yes	Go to the next step.
		No	Go to repair completion verification 2.
2	INSPECT BRAKE SWITCH (No.1 SIGNAL) CONNECTOR FOR MALFUNCTION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  Are the connector and terminal normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
3	INSPECT BRAKE SWITCH (No.1 SIGNAL) FOR MALFUNCTION •  Inspect the applicable part. (See BRAKE SWITCH INSPECTION.) •  Is the part normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See BRAKE PEDAL REMOVAL/INSTALLATION [L.H.D. (E)].) (See BRAKE PEDAL REMOVAL/INSTALLATION [R.H.D.].)
4	INSPECT BODY CONTROL MODULE (BCM) CONNECTOR FOR MALFUNCTION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  Are the connector and terminal normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT BRAKE SWITCH (No.1 SIGNAL) SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY •  Inspect the applicable circuit for a short to power supply. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED •  Install/connect the part removed/disconnected during the troubleshooting procedure. •  Clear the DTC recorded in the memory. (See CLEARING DTC.) •  Perform the work of depressing the brake pedal for 3 s or more and then releasing it for 5 times or more with the ignition switched ON (engine off or on). •  Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION.) •  Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. •  If the malfunction recurs, replace the body control module (BCM), then go to the next step. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)
		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTC IS DISPLAYED •  Perform the DTC inspection. (See DTC INSPECTION.) •  Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
		No	DTC troubleshooting completed.