DTC U3003:16/U3003:17 [BCM]

id0902f5310100

Malfunction Location

• DTC U3003:16: BCM power supply voltage low (less than 10 V)

• DTC U3003:17: BCM power supply voltage high (16 V or more)

Detection Condition

• DTC U3003:16: BCM power supply voltage less than 10 V

• DTC U3003:17: BCM power supply voltage 16 V or more

Possible Causes

• Battery malfunction

• Generator system malfunction

• BCM connector or terminals malfunction

• Short to ground or open circuit in wiring harness between battery and BCM

― Short to ground in wiring harness between positive battery terminal and BCM terminal 1P

― Short to ground in wiring harness between positive battery terminal and BCM terminal 1J

― D/L 20 A fuse malfunction

― HAZARD 10 A fuse malfunction

― Open circuit in wiring harness between positive battery terminal and BCM terminal 1P

― Open circuit in wiring harness between positive battery terminal and BCM terminal 1J

• BCM malfunction

System Wiring Diagram

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Diagnostic Procedure

Step

Inspection

Action

1

PERFORM DTC INSPECTION

•  Clear the DTCs using the M-MDS.
(See CLEARING DTC [BCM].)

•  Perform the BCM DTC inspection using the M-MDS.
(See DTC INSPECTION [BCM].)

•  Is the DTC U3003:16 or U3003:17 displayed?

Yes

Go to the next step.

No

DTC troubleshooting completed.

2

BATTERY INSPECTION

•  Refer to the battery inspection and inspect the battery.
(See BATTERY INSPECTION [ZJ, ZY].)

(See BATTERY INSPECTION [MZ-CD 1.4 DI Turbo].)

(See BATTERY INSPECTION [MZ-CD 1.6 (Y6)].)

•  Is the battery normal?

Yes

Go to the next step.

No

Recharge or replace the battery, then go to the final step.

(See BATTERY RECHARGING [ZJ, ZY].)

(See BATTERY RECHARGING [MZ-CD 1.4 DI Turbo].)

(See BATTERY RECHARGING [MZ-CD 1.6 (Y6)].)

(See BATTERY REMOVAL/INSTALLATION [ZJ, ZY].)

(See .BATTERY REMOVAL/INSTALLATION [MZ-CD 1.4 DI Turbo])

(See BATTERY REMOVAL/INSTALLATION [MZ-CD 1.6 (Y6)].)

3

GENERATOR INSPECTION

•  Inspect the generator.
(See GENERATOR INSPECTION [ZJ, ZY].)

(See GENERATOR INSPECTION [MZ-CD 1.4 DI Turbo].)

(See GENERATOR INSPECTION [MZ-CD 1.6 (Y6)].)

•  Is the generator normal?

Yes

Go to the next step.

No

Replace the generator, then go to the final step.

(See GENERATOR REMOVAL/INSTALLATION [ZJ, ZY].)

(See GENERATOR REMOVAL/INSTALLATION [MZ-CD 1.4 DI Turbo].)

(See GENERATOR REMOVAL/INSTALLATION [MZ-CD 1.6 (Y6)].)

4

VERIFY BCM CONNECTOR CONDITION

•  Turn the ignition switch to the LOCK position.

•  Disconnect the negative battery cable.

•  Disconnect the BCM connector.

•  Inspect the connection condition and wiring harness.

•  Are the connector terminals normal without damage, deformation, corrosion, or disconnection?

Yes

Go to the next step.

No

Repair or replace the connector, then go to the final step.

5

VERIFY WIRING HARNESS BETWEEN POSITIVE BATTERY TERMINAL AND BCM FOR SHORT TO GROUND OR OPEN CIRCUIT

•  BCM connector is disconnected.

•  Reconnect the negative battery cable.

•  Measure the voltage at the following terminals (wiring harness-side):

―  BCM terminal 1P

―  BCM terminal 1J

•  Is the voltage B+?

Yes

Go to the next step.

No

Inspect the D/L 20 A fuse and HAZARD 10 A fuse.

•  If the fuse is melt:

―  Repair or replace the wiring harness for a possible short to ground.

―  Replace the malfunctioning fuse.

•  If the fuse is deterioration:

―  Replace the malfunctioning fuse.

•  If the fuse is normal:

―  Repair or replace the wiring harness for a possible open circuit.

Go to the final step.

6

VERIFY TROUBLESHOOTING COMPLETED

•  Reconnect all disconnected connectors.

•  Reconnect the negative battery cable.

•  Clear the DTCs using the M-MDS.
(See CLEARING DTC [BCM].)

•  Perform the BCM DTC inspection using the M-MDS.
(See DTC INSPECTION [BCM].)

•  Is the DTC U3003:16 or U3003:17 displayed?

Yes

Replace the BCM.

(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)

No

DTC troubleshooting completed.

Step	Inspection		Action
1	PERFORM DTC INSPECTION • Clear the DTCs using the M-MDS. (See CLEARING DTC [BCM].) • Perform the BCM DTC inspection using the M-MDS. (See DTC INSPECTION [BCM].) • Is the DTC U3003:16 or U3003:17 displayed?	Yes	Go to the next step.
1		No	DTC troubleshooting completed.
2	BATTERY INSPECTION • Refer to the battery inspection and inspect the battery. (See BATTERY INSPECTION [ZJ, ZY].) (See BATTERY INSPECTION [MZ-CD 1.4 DI Turbo].) (See BATTERY INSPECTION [MZ-CD 1.6 (Y6)].) • Is the battery normal?	Yes	Go to the next step.
2		No	Recharge or replace the battery, then go to the final step. (See BATTERY RECHARGING [ZJ, ZY].) (See BATTERY RECHARGING [MZ-CD 1.4 DI Turbo].) (See BATTERY RECHARGING [MZ-CD 1.6 (Y6)].) (See BATTERY REMOVAL/INSTALLATION [ZJ, ZY].) (See .BATTERY REMOVAL/INSTALLATION [MZ-CD 1.4 DI Turbo]) (See BATTERY REMOVAL/INSTALLATION [MZ-CD 1.6 (Y6)].)
3	GENERATOR INSPECTION • Inspect the generator. (See GENERATOR INSPECTION [ZJ, ZY].) (See GENERATOR INSPECTION [MZ-CD 1.4 DI Turbo].) (See GENERATOR INSPECTION [MZ-CD 1.6 (Y6)].) • Is the generator normal?	Yes	Go to the next step.
3		No	Replace the generator, then go to the final step. (See GENERATOR REMOVAL/INSTALLATION [ZJ, ZY].) (See GENERATOR REMOVAL/INSTALLATION [MZ-CD 1.4 DI Turbo].) (See GENERATOR REMOVAL/INSTALLATION [MZ-CD 1.6 (Y6)].)
4	VERIFY BCM CONNECTOR CONDITION • Turn the ignition switch to the LOCK position. • Disconnect the negative battery cable. • Disconnect the BCM connector. • Inspect the connection condition and wiring harness. • Are the connector terminals normal without damage, deformation, corrosion, or disconnection?	Yes	Go to the next step.
4		No	Repair or replace the connector, then go to the final step.
5	VERIFY WIRING HARNESS BETWEEN POSITIVE BATTERY TERMINAL AND BCM FOR SHORT TO GROUND OR OPEN CIRCUIT • BCM connector is disconnected. • Reconnect the negative battery cable. • Measure the voltage at the following terminals (wiring harness-side): ― BCM terminal 1P ― BCM terminal 1J • Is the voltage B+?	Yes	Go to the next step.
5		No	Inspect the D/L 20 A fuse and HAZARD 10 A fuse. • If the fuse is melt: ― Repair or replace the wiring harness for a possible short to ground. ― Replace the malfunctioning fuse. • If the fuse is deterioration: ― Replace the malfunctioning fuse. • If the fuse is normal: ― Repair or replace the wiring harness for a possible open circuit. Go to the final step.
6	VERIFY TROUBLESHOOTING COMPLETED • Reconnect all disconnected connectors. • Reconnect the negative battery cable. • Clear the DTCs using the M-MDS. (See CLEARING DTC [BCM].) • Perform the BCM DTC inspection using the M-MDS. (See DTC INSPECTION [BCM].) • Is the DTC U3003:16 or U3003:17 displayed?	Yes	Replace the BCM. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)
6		No	DTC troubleshooting completed.