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DTC U2648:16 [DASH-ELECTRICAL SUPPLY UNIT (E)]

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Without Mazda M Hybrid

Outline

System malfunction location

Climate control unit low power supply voltage input

Detection condition

•  The dash-electrical supply unit detects that the voltage in the climate control unit power supply circuit is extremely low.

Fail-safe

•  Not applicable

Possible cause

•  DTCs are stored in the PCM.

•  Battery malfunction

•  Generator malfunction

•  Climate control unit connector or terminals malfunction

•  Short to ground or open circuit in climate control unit power supply circuit

•  Open circuit in climate control unit ground circuit

•  Climate control unit malfunction

•  Dash-electrical supply unit malfunction

System malfunction location	Climate control unit low power supply voltage input
Detection condition	• The dash-electrical supply unit detects that the voltage in the climate control unit power supply circuit is extremely low.
Fail-safe	• Not applicable
Possible cause	• DTCs are stored in the PCM. • Battery malfunction • Generator malfunction • Climate control unit connector or terminals malfunction • Short to ground or open circuit in climate control unit power supply circuit • Open circuit in climate control unit ground circuit • Climate control unit 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-G (E))].)

(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

Go to the next step.

No

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

(See BATTERY RECHARGING [(E)].)

(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].)

(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].)

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

3

INSPECT GENERATOR FOR MALFUNCTION

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

•  Is the part normal?

Yes

Go to the next step.

No

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

(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].)

(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION)].)

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

4

INSPECT CLIMATE CONTROL UNIT CONNECTOR FOR MALFUNCTION

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

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

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

5

INSPECT CLIMATE CONTROL UNIT 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 CLIMATE CONTROL UNIT GROUND CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for open circuit.
(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.

7

INSPECT CLIMATE CONTROL UNIT 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 CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].)

(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)

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-G (E))].) (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	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification. (See BATTERY RECHARGING [(E)].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
3	INSPECT GENERATOR FOR MALFUNCTION • Inspect the applicable part. (See GENERATOR INSPECTION [SKYACTIV-D 1.8].) • Is the part normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification. (See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].) (See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION)].) (See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-D 1.8].)
4	INSPECT CLIMATE CONTROL UNIT CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT CLIMATE CONTROL UNIT 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 CLIMATE CONTROL UNIT GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for open circuit. (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.
7	INSPECT CLIMATE CONTROL UNIT 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 CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)
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.

With Mazda M Hybrid

Outline

System malfunction location

Climate control unit low power supply voltage input

Detection condition

•  The dash-electrical supply unit detects that the voltage in the climate control unit power supply circuit is extremely low.

Fail-safe

•  Not applicable

Possible cause

•  DTCs are stored in the following modules.

―  PCM

―  Mazda M Hybrid battery

―  DC-DC converter (Mazda M Hybrid)

―  Integrated starter generator (ISG)

•  Battery malfunction

•  Climate control unit connector or terminals malfunction

•  Short to ground or open circuit in climate control unit power supply circuit

•  Open circuit in climate control unit ground circuit

•  Climate control unit malfunction

•  Dash-electrical supply unit malfunction

System malfunction location	Climate control unit low power supply voltage input
Detection condition	• The dash-electrical supply unit detects that the voltage in the climate control unit power supply circuit is extremely low.
Fail-safe	• Not applicable
Possible cause	• DTCs are stored in the following modules. ― PCM ― Mazda M Hybrid battery ― DC-DC converter (Mazda M Hybrid) ― Integrated starter generator (ISG) • Battery malfunction • Climate control unit connector or terminals malfunction • Short to ground or open circuit in climate control unit power supply circuit • Open circuit in climate control unit ground circuit • Climate control unit malfunction • Dash-electrical supply unit malfunction

Diagnostic procedure

Step

Inspection

Results

Action

1

VERIFY DTCs

•  Perform the DTC inspection for the following modules.
(See DTC INSPECTION.)

―  PCM

―  Mazda M Hybrid battery

―  DC-DC converter (Mazda M Hybrid)

―  Integrated starter generator (ISG)

•  Are any DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

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

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

(See DTC TABLE [Mazda M Hybrid BATTERY].)

(See DTC TABLE [DC-DC CONVERTER (Mazda M Hybrid)].)

(See DTC TABLE [INTEGRATED STARTER GENERATOR (ISG)].)

No

Go to the next step.

2

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 RECHARGING [(E)].)

(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].)

(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].)

(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)

3

INSPECT CLIMATE CONTROL UNIT CONNECTOR FOR MALFUNCTION

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

•  Are the connector and terminal normal?

Yes

Go to the next step.

No

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

4

INSPECT CLIMATE CONTROL UNIT 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.

5

INSPECT CLIMATE CONTROL UNIT GROUND CIRCUIT FOR OPEN CIRCUIT

•  Inspect the applicable circuit for open circuit.
(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 CLIMATE CONTROL UNIT 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 CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].)

(See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)

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	VERIFY DTCs • Perform the DTC inspection for the following modules. (See DTC INSPECTION.) ― PCM ― Mazda M Hybrid battery ― DC-DC converter (Mazda M Hybrid) ― Integrated starter generator (ISG) • Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-G (E))].) (See DTC TABLE [PCM (SKYACTIV-X)].) (See DTC TABLE [Mazda M Hybrid BATTERY].) (See DTC TABLE [DC-DC CONVERTER (Mazda M Hybrid)].) (See DTC TABLE [INTEGRATED STARTER GENERATOR (ISG)].)
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	Go to the next step.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See BATTERY RECHARGING [(E)].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
3	INSPECT CLIMATE CONTROL UNIT CONNECTOR FOR MALFUNCTION • Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) • Are the connector and terminal normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	INSPECT CLIMATE CONTROL UNIT 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.
4		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT CLIMATE CONTROL UNIT GROUND CIRCUIT FOR OPEN CIRCUIT • Inspect the applicable circuit for open circuit. (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 CLIMATE CONTROL UNIT 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 CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (E)].) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)
6		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.