Description

IG2 relay control circuit malfunction

Detection condition

• Front body control module (FBCM) detects an open circuit in the IG2 relay control circuit for 2 s or more with the ignition switched ON (engine off or on).

Fail-safe function

Not applicable

Possible cause

• Start stop unit connector or terminal malfunction

• Front body control module (FBCM) connector or terminal malfunction

• Open circuit in the wiring harness between start stop unit terminal 2D and front body control module (FBCM) terminal 2U

• Start stop unit malfunction

• Front body control module (FBCM) malfunction

Step

Inspection

Action

1

• Clear the DTC for the front body control module (FBCM) using the M-MDS.

  (See CLEARING DTC [FRONT BODY CONTROL MODULE (FBCM)].)

• Switch the ignition ON (engine off or on) and wait for 2 s or more.

• Retrieve the front body control module (FBCM) DTCs using the M-MDS.

  (See DTC INSPECTION [FRONT BODY CONTROL MODULE (FBCM)].)

• Is the same DTC displayed?

Yes

Go to the next step.

No

Go to Step 7.

2

• Switch the ignition off.

• Disconnect the negative battery cable.

  (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.5].)

• 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 6.

3

• Disconnect the front body control module (FBCM) 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 6.

4

• Verify that the start stop unit and front body control module (FBCM) connectors are disconnected.

• Inspect for continuity between start stop unit terminal 2D (wiring harness-side) and front body control module (FBCM) terminal 2U (wiring harness-side).

• 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 start stop unit terminal 2D and front body control module (FBCM) terminal 2U.

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 6.

5

• Inspect the start stop unit.

  (See START STOP UNIT INSPECTION.)

• Is the start stop unit normal?

Yes

Go to the next step.

No

Replace the start stop unit, then go to the next step.

(See START STOP UNIT REMOVAL/INSTALLATION.)

6

• Always reconnect all disconnected connectors.

• Reconnect the negative battery cable.

  (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.5].)

• Clear the DTC for the front body control module (FBCM) using the M-MDS.

  (See CLEARING DTC [FRONT BODY CONTROL MODULE (FBCM)].)

• Switch the ignition ON (engine off or on) and wait for 2 s or more.

• Retrieve the front body control module (FBCM) DTCs using the M-MDS.

  (See DTC INSPECTION [FRONT BODY CONTROL MODULE (FBCM)].)

• Is the same DTC displayed?

Yes

Repeat the inspection from Step 1.

• If the malfunction recurs, replace the front body control module (FBCM).

  (See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION.)

Go to the next step.

No

Go to the next step.

7

• Are any other DTCs displayed?

Yes

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

(See DTC TABLE [FRONT BODY CONTROL MODULE (FBCM)].)

No

DTC troubleshooting completed.