DTC U3003:16 [ELECTRICAL SUPPLY UNIT (ESU)]

id0902ff063700

Description

Electrical supply unit (ESU) power supply voltage low input
Detection condition
•  Electrical supply unit (ESU) power supply circuit (terminal 1H, 2P, or 2R) of less than 8 V is detected for 10 s or more.
Fail-safe
Not applicable
Possible cause
Without i-ELOOP:
•  DTCs are stored in the PCM.
•  Battery malfunction
•  Generator malfunction
•  Electrical supply unit (ESU) connector or terminal malfunction
•  Electrical supply unit (ESU) power supply circuit malfunction
―  Short to ground in the wiring harness between the following terminals:
•  METER1 10 A fuse—Electrical supply unit (ESU) terminal 1H
•  MAIN 200 A fuse—Electrical supply unit (ESU) terminal 2P
•  MAIN 200 A fuse—Electrical supply unit (ESU) terminal 2R
―  METER1 10 A fuse malfunction
―  INTERIOR 15 A fuse malfunction
―  ROOM 25 A fuse malfunction
―  F.WASHER 15 A fuse malfunction
―  CABIN+B 50 A fuse malfunction
―  MAIN 200 A fuse malfunction
―  Open circuit in wiring harness between the following terminals:
•  IG1 relay—Electrical supply unit (ESU) terminal 1H
•  Battery positive terminal—Electrical supply unit (ESU) terminal 2P
•  Battery positive terminal—Electrical supply unit (ESU) terminal 2R
•  Electrical supply unit (ESU) malfunction
With i-ELOOP:
•  DTCs are stored in the PCM.
•  DTCs are stored in the DC-DC converter (i-ELOOP).
―  DC-DC converter (i-ELOOP) connector or terminal malfunction
―  DC-DC converter (i-ELOOP) malfunction
•  Battery malfunction
•  Generator malfunction
•  Electrical supply unit (ESU) connector or terminal malfunction
•  Electrical supply unit (ESU) power supply circuit malfunction
―  Short to ground in the wiring harness between the following terminals:
•  METER1 10 A fuse—Electrical supply unit (ESU) terminal 1H
•  ROOM 25 A fuse—Electrical supply unit (ESU) terminal 2P
•  CABIN+B 50 A fuse—Electrical supply unit (ESU) terminal 2R
―  METER1 10 A fuse malfunction
―  INTERIOR 15 A fuse malfunction
―  ROOM 25 A fuse malfunction
―  F.WASHER 15 A fuse malfunction
―  CABIN+B 50 A fuse malfunction
―  Open circuit in wiring harness between the following terminals:
•  IG1 relay—Electrical supply unit (ESU) terminal 1H
•  DC-DC converter (i-ELOOP) terminal 4A—Electrical supply unit (ESU) terminal 2P
•  DC-DC converter (i-ELOOP) terminal 4A—Electrical supply unit (ESU) terminal 2R
•  Electrical supply unit (ESU) malfunction

Diagnostic Procedure

Step

Inspection

Action
1
VERIFY PCM DTCs
•  Retrieve the PCM DTCs using the M-MDS.
•  Are any DTCs displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE [PCM (SKYACTIV-G 1.5, SKYACTIV-G 2.0)].)
No
Without i-ELOOP:
•  Go to Step 3.
With i-ELOOP:
•  Go to the next step.
2
VERIFY DC-DC CONVERTER (i-ELOOP) DTCs
•  Retrieve the DC-DC converter (i-ELOOP) DTCs using the M-MDS.
•  Are any DTCs displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE [i-ELOOP].)
No
Go to the next step.
3
INSPECT BATTERY
•  Inspect the battery.
•  Is the battery normal?
Yes
Go to the next step.
No
Recharge or replace the battery, then go to Step 8.
(See BATTERY RECHARGING.)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0].)
4
INSPECT GENERATOR
•  Inspect the generator.
•  Is the generator normal?
Yes
Go to the next step.
No
Replace the generator, then go to Step 8.
(See GENERATOR REMOVAL/INSTALLATION [WITHOUT i-ELOOP (SKYACTIV-G 1.5, SKYACTIV-G 2.0)].)
(See GENERATOR REMOVAL/INSTALLATION [WITH i-ELOOP (SKYACTIV-G 1.5, SKYACTIV-G 2.0)].)
5
INSPECT ELECTRICAL SUPPLY UNIT (ESU) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the negative battery cable.
•  Disconnect the electrical supply unit (ESU) connector.
•  Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
•  Is the connector normal?
Yes
Without i-ELOOP:
•  Go to the next step.
With i-ELOOP:
•  Go to Step 7.
No
Repair or replace the connector, then go to Step 8.
6
VERIFY ELECTRICAL SUPPLY UNIT (ESU) POWER SUPPLY VOLTAGE
•  Connect the negative battery cable.
•  Measure the voltage at the following terminals (wiring harness-side):
―  Electrical supply unit (ESU) terminal 1H
―  Electrical supply unit (ESU) terminal 2P
―  Electrical supply unit (ESU) terminal 2R
•  Is the voltage B+?
Yes
Go to Step 8.
No
Inspect the METER1 10 A fuse, INTERIOR 15 A fuse, ROOM 25 A fuse, F.WASHER 15 A fuse, CABIN+B 50 A fuse and MAIN 200 A fuse.
•  Any fuse is blown:
―  Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  METER1 10 A fuse—Electrical supply unit (ESU) terminal 1H
•  MAIN 200 A fuse—Electrical supply unit (ESU) terminal 2P
•  MAIN 200 A fuse—Electrical supply unit (ESU) terminal 2R
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 a short to ground.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to ground.
•  Replace the fuse.
•  Any fuse is damaged:
―  Replace the fuse.
•  All fuses are normal:
―  Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  IG1 relay—Electrical supply unit (ESU) terminal 1H
•  Battery positive terminal—Electrical supply unit (ESU) terminal 2P
•  Battery positive terminal—Electrical supply unit (ESU) terminal 2R
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 8.
7
VERIFY ELECTRICAL SUPPLY UNIT (ESU) POWER SUPPLY VOLTAGE
•  Connect the negative battery cable.
•  Measure the voltage at the following terminals (wiring harness-side):
―  Electrical supply unit (ESU) terminal 1H
―  Electrical supply unit (ESU) terminal 2P
―  Electrical supply unit (ESU) terminal 2R
•  Is the voltage B+?
Yes
Go to the next step.
No
Disconnect the service plug.
(See SERVICE PLUG DISCONNECTION/CONNECTION [i-ELOOP].)
Inspect the METER1 10 A fuse, INTERIOR 15 A fuse, ROOM 25 A fuse, F.WASHER 15 A fuse and CABIN+B 50 A fuse.
•  Any fuse is blown:
―  Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  METER1 10 A fuse—Electrical supply unit (ESU) terminal 1H
•  ROOM 25 A fuse—Electrical supply unit (ESU) terminal 2P
•  CABIN+B 50 A fuse—Electrical supply unit (ESU) terminal 2R
If there is a common connector:
•  Determine the malfunctioning location by inspecting the common connector and terminals for corrosion, damage, or disconnection and by inspecting the DC-DC converter (i-ELOOP) terminal 4A-related wiring harness for a short to ground.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which is shorted to ground, or the DC-DC converter (i-ELOOP) terminal 4A-related wiring harness.
•  Replace the fuse.
•  Any fuse is damaged:
―  Replace the fuse.
•  All fuses are normal:
―  Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  IG1 relay—Electrical supply unit (ESU) terminal 1H
•  DC-DC converter (i-ELOOP) terminal 4A—Electrical supply unit (ESU) terminal 2P
•  DC-DC converter (i-ELOOP) terminal 4A—Electrical supply unit (ESU) terminal 2R
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.
Connect the service plug, then go to the next step.
(See SERVICE PLUG DISCONNECTION/CONNECTION [i-ELOOP].)
8
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Always reconnect all disconnected connectors.
•  Connect the negative battery cable.
•  Clear the DTC for the electrical supply unit (ESU) using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 10 s or more.
•  Retrieve the electrical supply unit (ESU) DTCs using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the electrical supply unit (ESU).
Go to the next step.
No
Go to the next step.
9
VERIFY IF OTHER DTCs DISPLAYED
•  Are any other DTCs displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
(See DTC TABLE [ELECTRICAL SUPPLY UNIT (ESU)].)
No
DTC troubleshooting completed.