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DTC B1528:16 [DASH-ELECTRICAL SUPPLY UNIT]

id0702k8011600

Outline

System malfunction location

PTC heater low power supply voltage input

Detection condition

•  The dash-electrical supply unit detects that the PTC heater power supply circuit voltage is extremely low.

Fail-safe

•  Stops the PTC heater output.

Possible cause

•  DTCs are stored in the PCM.

•  Battery malfunction

•  Generator malfunction

•  PTC heater connector or terminals malfunction

•  Short to ground or open circuit in PTC heater power supply circuit

•  PTC heater ground circuit malfunction

•  PTC heater malfunction

•  Dash-electrical supply unit malfunction

System malfunction location	PTC heater low power supply voltage input
Detection condition	• The dash-electrical supply unit detects that the PTC heater power supply circuit voltage is extremely low.
Fail-safe	• Stops the PTC heater output.
Possible cause	• DTCs are stored in the PCM. • Battery malfunction • Generator malfunction • PTC heater connector or terminals malfunction • Short to ground or open circuit in PTC heater power supply circuit • PTC heater ground circuit malfunction • PTC heater malfunction • Dash-electrical supply unit malfunction

Diagnostic Procedure

Step

Inspection

Results

Action

1

INSPECT PCM FOR MALFUNCTION

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

•  Are any DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [PCM (SKYACTIV-D)].)

No

Go to the next step.

2

INSPECT BATTERY FOR MALFUNCTION

•  Inspect the applicable part.
(See BATTERY INSPECTION [(E)].)

•  Is the part normal?

Yes

Repair or replace the malfunctioning location and perform the repair completion verification.

(See BATTERY RECHARGING [(E)].)

(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

No

Go to the next step.

3

INSPECT GENERATOR FOR MALFUNCTION

•  Inspect the applicable part.
(See GENERATOR INSPECTION [SKYACTIV-D 1.8].)

•  Is the part normal?

Yes

Repair or replace the malfunctioning location and perform the repair completion verification.

(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)

No

Go to the next step.

4

INSPECT PTC HEATER CONNECTOR FOR MALFUNCTION

•  Inspect the applicable connector and terminal.
(See CONNECTOR INSPECTION.)

•  Are the connector and terminal normal?

Yes

Repair or replace the malfunctioning location and perform the repair completion verification.

No

Go to the next step.

5

INSPECT PTC HEATER POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT

•  Inspect the power supply circuit for an open circuit and short to ground.
(See CIRCUIT INSPECTION.)

•  Is the circuit normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

6

INSPECT PTC HEATER FOR POOR GROUND

•  Verify the PTC heater ground point condition.
(See POSITIVE TEMPERATURE COEFFICIENT (PTC) HEATER REMOVAL/INSTALLATION.)

•  Is there any ground point loose or lifting in the PTC heater?

Yes

Repair or replace the malfunctioning location and perform the repair completion verification.

No

Go to the next step.

7

INSPECT PTC HEATER FOR MALFUNCTION DEPENDING ON REPEATABILITY

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

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

•  Perform the DTC inspection for the dash-electrical supply unit.
(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, replace the malfunctioning location and perform the repair completion verification.

(See POSITIVE TEMPERATURE COEFFICIENT (PTC) HEATER REMOVAL/INSTALLATION.)

No

Go to repair completion verification 2.

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 DTC inspection for the dash-electrical supply unit.
(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 dash-electrical supply unit, then go to the next step.
(See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].)

(See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)

No

Go to the next step.

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	INSPECT PCM FOR MALFUNCTION • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-D)].)
1		No	Go to the next step.
2	INSPECT BATTERY FOR MALFUNCTION • Inspect the applicable part. (See BATTERY INSPECTION [(E)].) • Is the part normal?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification. (See BATTERY RECHARGING [(E)].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
2		No	Go to the next step.
3	INSPECT GENERATOR FOR MALFUNCTION • Inspect the applicable part. (See GENERATOR INSPECTION [SKYACTIV-D 1.8].) • Is the part normal?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification. (See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
3		No	Go to the next step.
4	INSPECT PTC HEATER CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
4		No	Go to the next step.
5	INSPECT PTC HEATER POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT • Inspect the power supply circuit for an open circuit and short to ground. (See CIRCUIT INSPECTION.) • Is the circuit normal?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT PTC HEATER FOR POOR GROUND • Verify the PTC heater ground point condition. (See POSITIVE TEMPERATURE COEFFICIENT (PTC) HEATER REMOVAL/INSTALLATION.) • Is there any ground point loose or lifting in the PTC heater?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
6		No	Go to the next step.
7	INSPECT PTC HEATER FOR MALFUNCTION DEPENDING ON REPEATABILITY • Install/connect the part removed/disconnected during the troubleshooting procedure. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the DTC inspection for the dash-electrical supply unit. (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, replace the malfunctioning location and perform the repair completion verification. (See POSITIVE TEMPERATURE COEFFICIENT (PTC) HEATER REMOVAL/INSTALLATION.)
7		No	Go to repair completion verification 2.
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 DTC inspection for the dash-electrical supply unit. (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 dash-electrical supply unit, then go to the next step. (See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].) (See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)
Repair completion verification 1		No	Go to the next step.
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.