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DTC C112A:77 [DSC HU/CM]

id040262008300

Outline

System malfunction location

Incorrect electric parking brake motor gear unit position

Detection condition

•  The DSC HU/CM detects any of the following conditions.

―  Operate/release positions of electric parking brake motor gear unit (LH) and (RH) do not correspond

―  Operate/release position of electric parking brake motor gear unit (LH) or (RH) is unknown

Fail-safe

Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”.(See DTC TABLE [DSC HU/CM (E)].)

Possible cause

Note

•  If the negative battery terminal is disconnected during electric parking brake operation, this DTC may be output.

•  DSC HU/CM malfunction

System wiring diagram

Not applicable

Connector diagram

Not applicable

System malfunction location	Incorrect electric parking brake motor gear unit position
Detection condition	• The DSC HU/CM detects any of the following conditions. ― Operate/release positions of electric parking brake motor gear unit (LH) and (RH) do not correspond ― Operate/release position of electric parking brake motor gear unit (LH) or (RH) is unknown
Fail-safe	Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”.(See DTC TABLE [DSC HU/CM (E)].)
Possible cause	Note • If the negative battery terminal is disconnected during electric parking brake operation, this DTC may be output. • DSC HU/CM malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY OTHER DSC HU/CM DTCs

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the following procedure 3 times or more.

―  Pull up the electric parking brake switch to operate the electric parking brake.

―  Press down the electric parking brake switch to release the electric parking brake.

•  Perform the DTC inspection for the DSC HU/CM.
(See DTC INSPECTION.)

•  Are any DTCs other than this DTC displayed?

Yes

If a procedure which verifies other DTCs is included in the diagnostic procedure of the displayed DTC:

•  Go to the next step.

If a procedure which verifies other DTCs is not included in the diagnostic procedure of the displayed DTC:

•  Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [DSC HU/CM (E)].)

No

Go to the next step.

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 following procedure 3 times or more.

―  Pull up the electric parking brake switch to operate the electric parking brake.

―  Press down the electric parking brake switch to release the electric parking brake.

•  Perform the DTC inspection for the DSC HU/CM.
(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 DSC HU/CM, then go to the next step.
(See DSC HU/CM REMOVAL/INSTALLATION [L.H.D. (E)].)

(See DSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)

No

System is normal. (Explain to the customer that a DTC is displayed by disconnecting the negative battery terminal during electric parking brake operation.)

Repair completion verification 2

VERIFY IF OTHER DTCs DISPLAYED

•  Perform the DTC inspection.
(See DTC INSPECTION.)

•  Are any DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.

Step	Inspection	Results	Action
1	VERIFY OTHER DSC HU/CM DTCs • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the following procedure 3 times or more. ― Pull up the electric parking brake switch to operate the electric parking brake. ― Press down the electric parking brake switch to release the electric parking brake. • Perform the DTC inspection for the DSC HU/CM. (See DTC INSPECTION.) • Are any DTCs other than this DTC displayed?	Yes	If a procedure which verifies other DTCs is included in the diagnostic procedure of the displayed DTC: • Go to the next step. If a procedure which verifies other DTCs is not included in the diagnostic procedure of the displayed DTC: • Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [DSC HU/CM (E)].)
1		No	Go to the next step.
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 following procedure 3 times or more. ― Pull up the electric parking brake switch to operate the electric parking brake. ― Press down the electric parking brake switch to release the electric parking brake. • Perform the DTC inspection for the DSC HU/CM. (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 DSC HU/CM, then go to the next step. (See DSC HU/CM REMOVAL/INSTALLATION [L.H.D. (E)].) (See DSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)
Repair completion verification 1		No	System is normal. (Explain to the customer that a DTC is displayed by disconnecting the negative battery terminal during electric parking brake operation.)
Repair completion verification 2	VERIFY IF OTHER DTCs DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.