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DTC P1708:29 [START STOP UNIT]

Description	Starter interlock switch circuit or clutch pedal position switch circuit malfunction
Detection condition	Start stop unit detects that the starter interlock switch circuit is stuck on for 0.2 s or more, or the clutch pedal position switch circuit is stuck off for 0.25 s or more.
Fail-safe	Change to the back-up mode. Perform the control with starter interlock switch turned off. (Starter interlock switch circuit malfunction)
Possible cause	Starter interlock switch connector or terminal malfunction Starter interlock switch malfunction Start stop unit connector or terminal malfunction Short to ground in wiring harness between start stop unit terminal 1F and starter interlock switch terminal A Clutch pedal position switch connector or terminal malfunction Open circuit in wiring harness between clutch pedal position switch terminal B and body ground Clutch pedal position switch malfunction Open circuit in wiring harness between start stop unit terminal 2E and clutch pedal position switch terminal A Start stop unit malfunction

Diagnostic Procedure

Step	Inspection		Action
1	PERFORM PID/DATA MONITOR INSPECTION AND DETERMINE MALFUNCTIONING LOCATION Display the following PIDs using the M-MDS. (See PID/DATA MONITOR INSPECTION [START STOP UNIT].) CLUT_CUT_SW (Starter interlock switch) CLUTCH_SW (Clutch pedal position switch) Are all PID values normal? (See PID/DATA MONITOR TABLE [START STOP UNIT].)	Yes	Go to Step 12.
		No	If the PID CLUT_CUT_SW value is not normal: Go to the next step. If the PID CLUTCH_SW value is not normal: Go to Step 6. If all PID values are not normal: Go to Step 11.
2	INSPECT STARTER INTERLOCK SWITCH CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.) Disconnect the starter interlock 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.
		No	Repair or replace the connector, then go to Step 12.
3	INSPECT STARTER INTERLOCK SWITCH Inspect the starter interlock switch. (See STARTER INTERLOCK SWITCH INSPECTION [SKYACTIV-G 2.0].) Is the starter interlock switch normal?	Yes	Go to the next step.
		No	Replace the starter interlock switch, then go to Step 12. (See STARTER INTERLOCK SWITCH REMOVAL/INSTALLATION.)
4	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.
		No	Repair or replace the connector, then go to Step 12.
5	INSPECT STARTER INTERLOCK SWITCH CIRCUIT FOR SHORT TO GROUND Verify that the start stop unit and starter interlock switch connectors are disconnected. Inspect for continuity between starter interlock switch terminal A (wiring harness-side) and body ground. Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between start stop unit terminal 1F and starter interlock switch terminal A. 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 ground. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to ground. Go to Step 12.
		No	Go to Step 12.
6	INSPECT CLUTCH PEDAL POSITION SWITCH CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.) Disconnect the clutch pedal position 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.
		No	Repair or replace the connector, then go to Step 12.
7	INSPECT CLUTCH PEDAL POSITION SWITCH GROUND CIRCUIT FOR OPEN CIRCUIT Verify that the clutch pedal position switch connector is disconnected. Inspect for continuity between clutch pedal position switch terminal B (wiring harness-side) and body ground. Is there continuity?	Yes	Go to the next step.
		No	Refer to the wiring diagram and verify whether or not there is a common connector between clutch pedal position switch terminal B and body ground. 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 an open circuit. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has an open circuit. Go to Step 12.
8	INSPECT CLUTCH PEDAL POSITION SWITCH Inspect the clutch pedal position switch. (See CLUTCH PEDAL POSITION (CPP) SWITCH INSPECTION [SKYACTIV-G 2.0].) Is the clutch pedal position switch normal?	Yes	Go to the next step.
		No	Replace the clutch pedal position switch, then go to the Step 12. (See CLUTCH PEDAL POSITION SWITCH REMOVAL/INSTALLATION.)
9	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.
		No	Repair or replace the connector, then go to Step 12.
10	INSPECT CLUTCH PEDAL POSITION SWITCH CIRCUIT FOR OPEN CIRCUIT Verify that the clutch pedal position switch and start stop unit connectors are disconnected. Inspect for continuity between start stop unit terminal 2E (wiring harness-side) and clutch pedal position switch terminal A (wiring harness-side). Is there continuity?	Yes	Go to Step 12.
		No	Refer to the wiring diagram and verify whether or not there is a common connector between start stop unit terminal 2E and clutch pedal position switch terminal A. 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 an open circuit. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has an open circuit. Go to Step 12.
11	INSPECT START STOP UNIT CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.) 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.
		No	Repair or replace the connector, then go to the next step.
12	VERIFY THAT REPAIRS HAVE BEEN COMPLETED Always reconnect all disconnected connectors. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.) Clear the DTC for the start stop unit using the M-MDS. (See CLEARING DTC [START STOP UNIT].) Switch the ignition ON (engine off or on). Perform the work of depressing and releasing the clutch pedal 3 times. 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.
		No	Go to the next step.
13	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].)
		No	DTC troubleshooting completed.

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DTC P1708:29 [START STOP UNIT]