DTC P0A8D:00 [PCM (SKYACTIV-D)]

Description	Power supply system circuit low input
Detection condition	Determination conditions	• Any one of the following conditions is met: ― Battery voltage is 7.25 V or less when engine restarts from i-stop. ― DC-DC converter terminal voltage is 6 V or less when engine restarts from i-stop. ― PCM terminal voltage is 6.2 V or less when engine starts. ― Battery internal resistance is specified value or more.
Preconditions	• Not applicable
Drive cycle	• 1
Self test type	• CMDTC self test
Sensor used	• Current sensor
Fail-safe	• Inhibits engine-stop by operating the i-stop function.
Vehicle status when dtcs are output	• Flashes i-stop warning light (amber). • Illuminates master warning light • The engine may not start, it may stall, or it may not restart by i-stop due to a battery voltage decrease.
Possible cause	• Battery performance decrease or malfunction • Connector or terminal malfunction of the following parts: ― Battery ― Current sensor ― PCM ― DC-DC converter • Malfunction in the following fuses: ― GLOW/DCDC 80 A fuse ― F55 50 A fuse • Short to ground in DC-DC converter power supply circuit • Open circuit in DC-DC converter power supply circuit • Current sensor malfunction • DC-DC converter malfunction • PCM malfunction

Description

Power supply system circuit low input

Detection condition

Determination conditions

• Any one of the following conditions is met:

― Battery voltage is 7.25 V or less when engine restarts from i-stop.

― DC-DC converter terminal voltage is 6 V or less when engine restarts from i-stop.

― PCM terminal voltage is 6.2 V or less when engine starts.

― Battery internal resistance is specified value or more.

Preconditions

• Not applicable

Drive cycle

• 1

Self test type

• CMDTC self test

Sensor used

• Current sensor

Fail-safe

• Inhibits engine-stop by operating the i-stop function.

Vehicle status when dtcs are output

• Flashes i-stop warning light (amber).

• Illuminates master warning light

• The engine may not start, it may stall, or it may not restart by i-stop due to a battery voltage decrease.

Possible cause

• Battery performance decrease or malfunction

• Connector or terminal malfunction of the following parts:

― Battery

― Current sensor

― PCM

― DC-DC converter

• Malfunction in the following fuses:

― GLOW/DCDC 80 A fuse

― F55 50 A fuse

• Short to ground in DC-DC converter power supply circuit

• Open circuit in DC-DC converter power supply circuit

• Current sensor malfunction

• DC-DC converter malfunction

• PCM malfunction

• The PCM assures engine startability and power during driving based on control of the battery related parts. The PCM detects the battery voltage during engine starting and the battery internal resistance based on the current sensor signal, and if the battery voltage during engine starting is low or the battery internal resistance is high, it determines that there is a malfunction in the battery related parts and stores a DTC.

PIDs	Reference
BATT_CUR	(See PID/DATA MONITOR TABLE [PCM (SKYACTIV-D)].)
VPWR

PIDs

Reference

BATT_CUR

(See PID/DATA MONITOR TABLE [PCM (SKYACTIV-D)].)

VPWR

Step	Inspection	Results	Action
1	PURPOSE: VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY • Verify related Service Bulletins, on-line repair information, or Service Information availability. • Is any related Information available?	Yes	Perform repair or diagnosis according to the available information. • If the vehicle is not repaired, go to the next step.
No	Go to the next step.
2	PURPOSE: RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION • Record the freeze frame data/snapshot data. Note • Recording can be facilitated using the screen capture function of the PC.	—	Go to the next step.
3	PURPOSE: VERIFY IF POWER SUPPLY IS AFFECTED BY DTC RELATED TO DC-DC CONVERTER • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-D)].) Go to the next step.
No	Go to the next step.
4	PURPOSE: VERIFY IF BATTERY VOLTAGE IS FALSELY RECOGNIZED BY DTC RELATED CURRENT SENSOR • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Are any of the following DTCs displayed? ― P058A:00	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC P058A:00 [PCM (SKYACTIV-D)].) Go to the next step.
No	Go to the next step.
5	PURPOSE: VERIFY IF BATTERY VOLTAGE IS FALSELY RECOGNIZED BY DTC RELATED CAN OR LIN COMMUNICATION • Perform the DTC inspection for the PCM. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-D)].) Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.
No	Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.

Step

Inspection

Results

Action

PURPOSE: VERIFY RELATED REPAIR INFORMATION OR SERVICE INFORMATION AVAILABILITY

• Verify related Service Bulletins, on-line repair information, or Service Information availability.

• Is any related Information available?

Yes

Perform repair or diagnosis according to the available information.

• If the vehicle is not repaired, go to the next step.

Go to the next step.

PURPOSE: RECORD VEHICLE STATUS WHEN DTC WAS DETECTED TO UTILIZE WITH REPEATABILITY VERIFICATION

• Record the freeze frame data/snapshot data.

Note

• Recording can be facilitated using the screen capture function of the PC.

—

Go to the next step.

PURPOSE: VERIFY IF POWER SUPPLY IS AFFECTED BY DTC RELATED TO DC-DC CONVERTER

• Perform the DTC inspection for the PCM.

(See DTC INSPECTION.)

• Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

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

Go to the next step.

PURPOSE: VERIFY IF BATTERY VOLTAGE IS FALSELY RECOGNIZED BY DTC RELATED CURRENT SENSOR

• Perform the DTC inspection for the PCM.

(See DTC INSPECTION.)

• Are any of the following DTCs displayed?

― P058A:00

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC P058A:00 [PCM (SKYACTIV-D)].)

Go to the next step.

PURPOSE: VERIFY IF BATTERY VOLTAGE IS FALSELY RECOGNIZED BY DTC RELATED CAN OR LIN COMMUNICATION

• Perform the DTC inspection for the PCM.

(See DTC INSPECTION.)

• Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

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

Go to Troubleshooting Diagnostic Procedure to perform the procedure from Step 1.

Step	Inspection	Results	Action
1	PURPOSE: INSPECT BATTERY FOR MALFUNCTION • Inspect the applicable part. (See BATTERY INSPECTION [(E)].) • Is the part normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification. (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
2	PURPOSE: VERIFY IF CONNECTOR DAMAGE OF EACH PART AFFECTS DIAGNOSTIC RESULTS • Switch the ignition off. • Disconnect the connector of the following parts. ― Battery ― Current sensor ― PCM ― DC-DC converter • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
No	Go to the next step.
3	PURPOSE: INSPECT F55 50 A FUSE • Remove the F55 50 A Fuse. • Inspect the F55 50 A Fuse. • Is the fuse normal?	Yes	Reinstall the F55 50 A Fuse, then go to the next step.
No	Replace the F55 50 A Fuse and perform the repair completion verification.
4	PURPOSE: INSPECT GLOW/DCDC 80 A FUSE • Remove the GLOW/DCDC 80 A Fuse. • Inspect the GLOW/DCDC 80 A Fuse. • Is the fuse normal?	Yes	Reinstall the GLOW/DCDC 80 A Fuse, then go to the next step.
No	Replace the GLOW/DCDC 80 A Fuse and perform the repair completion verification.
5	PURPOSE: INSPECT DC-DC CONVERTER 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.
Repair completion verification 1	PURPOSE: 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.) • Replicate the vehicle conditions at the time the DTC was detected using the following procedure. ― Implement the repeatability verification procedure. (See Repeatability verification procedure.) • Perform the DTC inspection for the PCM. (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 PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
No	Go to the next step.
Repair completion verification 2	PURPOSE: VERIFY IF OTHER DTCs DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
No	DTC troubleshooting completed.

Step

Inspection

Results

Action

PURPOSE: INSPECT BATTERY FOR MALFUNCTION

• Inspect the applicable part.

(See BATTERY INSPECTION [(E)].)

• Is the part normal?

Yes

Go to the next step.

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

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

PURPOSE: VERIFY IF CONNECTOR DAMAGE OF EACH PART AFFECTS DIAGNOSTIC RESULTS

• Switch the ignition off.

• Disconnect the connector of the following parts.

― Battery

― Current sensor

― PCM

― DC-DC converter

• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).

• Is there any malfunction?

Yes

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

Go to the next step.

PURPOSE: INSPECT F55 50 A FUSE

• Remove the F55 50 A Fuse.

• Inspect the F55 50 A Fuse.

• Is the fuse normal?

Yes

Reinstall the F55 50 A Fuse, then go to the next step.

Replace the F55 50 A Fuse and perform the repair completion verification.

PURPOSE: INSPECT GLOW/DCDC 80 A FUSE

• Remove the GLOW/DCDC 80 A Fuse.

• Inspect the GLOW/DCDC 80 A Fuse.

• Is the fuse normal?

Yes

Reinstall the GLOW/DCDC 80 A Fuse, then go to the next step.

Replace the GLOW/DCDC 80 A Fuse and perform the repair completion verification.

PURPOSE: INSPECT DC-DC CONVERTER 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.

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

Repair completion verification 1

PURPOSE: 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.)

• Replicate the vehicle conditions at the time the DTC was detected using the following procedure.

― Implement the repeatability verification procedure.

(See Repeatability verification procedure.)

• Perform the DTC inspection for the PCM.

(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 PCM, then go to the next step.

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

Go to the next step.

Repair completion verification 2

PURPOSE: VERIFY IF OTHER DTCs DISPLAYED

• Perform the DTC inspection.

(See DTC INSPECTION.)

• Are any other DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

DTC troubleshooting completed.

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