Description

Starter relay circuit malfunction

Detection condition

• Start stop unit detects that the starter relay circuit voltage of specification or more for 0.1 s or more with the ignition switched off.

Fail-safe

• Inhibits switching the ignition ON (engine off or on).

• Inhibits the engine start.

Possible cause

• DTCs are stored in the PCM.

• Starter relay malfunction

• Start stop unit connector or terminal malfunction

• PCM connector malfunction

• Short to power supply in wiring harness between the following terminals:

• Start stop unit terminal 1D—Starter relay terminal E

• Starter relay terminal E—PCM terminal 2AZ

• Start stop unit terminal 2V—Starter relay terminal A

• PCM malfunction

• Start stop unit malfunction

Step

Inspection

Action

1

• Retrieve the PCM DTCs using the M-MDS.

  (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0)].)

• Are any DTCs displayed?

Yes

Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.

(See DTC TABLE [PCM (SKYACTIV-G 2.0)].)

No

Go to the next step.

2

• Switch the ignition off.

• Disconnect the negative battery cable.

  (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.)

• Remove the starter relay.

  (See RELAY LOCATION.)

• Inspect the starter relay.

  (See RELAY INSPECTION.)

• Is the starter relay normal?

Yes

Go to the next step.

No

Replace the starter relay, then go to Step 7.

(See RELAY LOCATION.)

3

• 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 7.

4

• Disconnect the PCM 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 7.

5

• Verify that the starter relay is removed.

• Verify that the start stop unit and PCM connectors are disconnected.

• Connect the negative battery cable.

  (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION.)

• Measure the voltage at the following terminals (wiring harness-side):

• Start stop unit terminal 1D

• Start stop unit terminal 2V

• Is the voltage 0 V?

Yes

Go to the next step.

No

Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:

• Start stop unit terminal 1D—Starter relay terminal E

• Starter relay terminal E—PCM terminal 2AZ

• Start stop unit terminal 2V—Starter relay 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 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 Step 7.

6

• 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 off and wait for 1 s or more.

• Retrieve the start stop unit DTCs using the M-MDS.

  (See DTC INSPECTION [START STOP UNIT].)

• Is the same DTC displayed?

Yes

Replace the PCM, then go to the next step.

(See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.0].)

No

Go to Step 8.

7

• 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 off and wait for 1 s or more.

• 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.

8

• 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.