Diagnostic Procedure

DTC C0040-24; BRAKE SWITCH (NO. 1 SIGNAL) CIRCUIT MALFUNCTION - DIAGNOSTIC PROCEDURE

Step	Inspection		Action
1	INSPECT BRAKE SWITCH CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .) Disconnect the brake switch connector. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. Is the connector normal?	Yes	Go to the next step.
1		No	Repair or replace the connector, then go to Step 5.
2	INSPECT BRAKE SWITCH (No. 1 SIGNAL) Inspect the brake switch (No. 1 signal). (See BRAKE SWITCH INSPECTION .) Is the brake switch (No. 1 signal) normal?	Yes	Go to the next step.
2		No	Replace the brake switch, then go to Step 5. (See BRAKE PEDAL REMOVAL/INSTALLATION .)
3	INSPECT START STOP UNIT CONNECTOR CONDITION Disconnect the start stop unit connector. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. Is the connector normal?	Yes	Go to the next step.
3		No	Repair or replace the connector, then go to Step 5.
4	INSPECT BRAKE SWITCH (No. 1 SIGNAL) CIRCUIT FOR SHORT TO POWER SUPPLY Verify that the brake switch and start stop unit connectors are disconnected. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .) Switch the ignition ON (engine off or on). Measure the voltages at brake switch terminal D (wiring harness-side). Is the voltage 0 V?	Yes	Go to the next step.
4		No	Refer to the wiring diagram and verify whether or not there is a common connector between brake switch terminal D and start stop unit terminal 1C. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to power supply. Go to the next step.
5	VERIFY THAT REPAIRS HAVE BEEN COMPLETED Always reconnect all disconnected connectors. Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .) Clear the DTC for the start stop unit using the M-MDS. (See CLEARING DTC [START STOP UNIT] .) 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). Retrieve the start stop unit DTCs using the M-MDS. (See DTC INSPECTION [START STOP UNIT] .) Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the start stop unit. (See START STOP UNIT REMOVAL/INSTALLATION .) Go to the next step.
5		No	Go to the next step.
6	VERIFY IF OTHER DTCs DISPLAYED Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [START STOP UNIT] .)
6		No	DTC troubleshooting completed.