U3003-16 Brake Booster Control Unit Power Circuit (+B) Low Voltage
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, then wait 5 seconds or more.
NOTE: Do not open and close the driver's door.
?4.
Turn the vehicle to the ON mode.
?5.
Check for DTCs with the HDS.
DTC Description
DTC
Freeze Frame
U3003-16 Brake Booster Control Unit Power Circuit (+B) Low Voltage
Is DTC U3003-16 indicated?
YES
The failure is duplicated. Go to step 2.
NO
Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting. 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.
Fuse check:
Fuse check
?1.
Turn the vehicle to the OFF (LOCK) mode with driver's door open.
?2.
Wait for 3 minutes.
NOTE: Do not close the driver's door.
?3.
Check the following fuse.
Fuse
No. A1-2 (40 A)
Location
Under-hood fuse/relay box
Is the fuse OK?
YES
The fuse is OK. Reinstall the fuse, then go to step 3.
NO
Replace the fuse. If the fuse blows again, repair a short to ground in the No. A1-2 (40 A) fuse circuit.?
3.
Open wire check (+B EBB line):
Open wire check (+B EBB line)
?1.
Disconnect the following connector.
Electric brake booster 26P connector
?2.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
Electric brake booster 26P connector: disconnected
Check for loose terminals and poor connections in the electric brake booster 26P connector. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting. If they are OK, replace the electric brake booster.?
NO
Repair an open in the wire between the electric brake booster and the under-hood fuse/relay box.?