DTC Troubleshooting: U3003-16
DTC U3003-16: Battery Voltage Low
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
DTC
Freeze Frame
U3003-16 Battery Voltage Low
    

1.
Problem verification:

Problem verification
?1.
Turn the vehicle to the ON mode.

?2.
Clear the DTC with the HDS.


?3.
Turn the vehicle to the OFF (LOCK) mode, start the engine.

?4.
Wait for 5 seconds or more.

?5.
Check for DTCs with the HDS.
DTC Description
DTC
Freeze Frame
U3003-16 Battery Voltage Low
    

Is DTC U3003-16 indicated?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the Freeze data/on-board snapshot.?
2.
Power source performance check:

Power source performance check
?1.
Check and note the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
BATTERY VOLTAGE
    

?2.
Using a voltmeter, measure and note the voltage across the battery terminals.
NOTE: If the voltage is below 8.0 V, check the 12 volt battery, and check the PGM-FI DTCs.

?3.
Compare the voltage noted in step 2-1 to the voltage in step 2-2.

Is the difference between the two voltage readings less than 3 V?

     
YES
     
     
     
     
NO
     
     
     
Go to step 3.
3.
Fuse check:

Fuse check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Check the following fuse.
Fuse
No. A2-1 (70 A)
Location
Under-hood fuse/relay box

Is the fuse OK?

     
YES
     
     
     
The fuse is OK. Reinstall the fuse, then go to step 4.
     
NO
     
     
     
Replace the fuse. If the fuse blows again, repair a short to ground in the No. A2-1 (70 A) fuse circuit.?
4.
Connector check (EPS control unit connector A):

Connector check (EPS control unit connector A)
?1.
Check for loose terminal and poor connection at the following connector.
EPS control unit connector A (2P)

Is the connetor OK?

     
YES
     
     
     
Go to step 5.
     
NO
     
     
     
Repair loose terminal or poor connection. Then clear the DTC by using the HDS and recheck DTC U3003-16. If DTC U3003-16 is not confirmed, troubleshooting is complete.?
5.
Open wire check (+B EPS line):

Open wire check (+B EPS line)
?1.
Disconnect the following connector.
EPS control unit connector A (2P)

?2.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
EPS control unit connector A (2P): disconnected
Test point 1
EPS control unit connector A (2P) No. 2
Test point 2
Body ground

Is there battery voltage?

     
YES
     
     
     
Check for loose terminals and poor connections at the EPS control unit connectors. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting. If they are OK, replace the EPS motor/control unit.?
     
NO
     
     
     
Repair an open in the wire between the EPS motor/control unit and the No. A2-1 (70 A) fuse.?