DTC U3003:16 [FRONT BODY CONTROL MODULE (FBCM)]


id0902p2011600

Description

Front body control module (FBCM) power supply voltage (+B power supply) low input

Detection condition
•  Front body control module (FBCM) power supply circuit voltage of 8.8 V or less is detected for 10 s or more with the ignition switched ON (engine off or on).
Fail-safe function
Not applicable
Possible cause
•  DTCs are stored in the PCM.
•  Battery malfunction
•  Generator malfunction
•  Front body control module (FBCM) connector or terminal malfunction
•  Front body control module (FBCM) power supply circuit malfunction
―  Short to ground in the wiring harness between the following:
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 2A
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 1A
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 1B
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 3K
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 3L
―  ROOM 15 A fuse malfunction
―  HAZARD 25 A fuse malfunction
―  MAIN 200 A fuse malfunction
―  Open circuit in wiring harness between the following terminals:
•  Battery positive terminal—Front body control module (FBCM) terminal 2A
•  Battery positive terminal—Front body control module (FBCM) terminal 1A
•  Battery positive terminal—Front body control module (FBCM) terminal 1B
•  Battery positive terminal—Front body control module (FBCM) terminal 3K
•  Battery positive terminal—Front body control module (FBCM) terminal 3L
•  Front body control module (FBCM) malfunction

Diagnostic Procedure

Step

Inspection

Action

1
VERIFY FRONT BODY CONTROL MODULE (FBCM) DTCs AGAIN
•  Clear the DTC for the front body control module (FBCM) using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 10 s or more.
•  Retrieve the front body control module (FBCM) DTCs using the M-MDS.
•  Is the same DTC displayed?
Yes
Go to the next step.
No
Go to Step 8.
2
VERIFY PCM DTCs
•  Are any DTCs displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
No
Go to the next step.
3
INSPECT BATTERY
•  Is the battery normal?
Yes
Go to the next step.
No
Recharge or replace the battery, then go to Step 7.
4
INSPECT GENERATOR
•  Is the generator normal?
Yes
Go to the next step.
No
Replace the generator, then go to Step 7.
5
INSPECT FRONT BODY CONTROL MODULE (FBCM) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the front body control module (FBCM) connector.
•  Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
•  Is the connector normal?
Yes
Go to the next step.
No
Repair or replace the connector, then go to Step 7.
6
VERIFY FRONT BODY CONTROL MODULE (FBCM) POWER SUPPLY VOLTAGE
•  Always reconnect all disconnected connectors.
•  Display the PID VPWR_B using the M-MDS.
•  Is the voltage B+?
Yes
Go to the next step.
No
Inspect the ROOM 15 A fuse, HAZARD 25 A fuse and MAIN 200 A fuse.
•  If the fuse is blown:
―  Refer to the wiring diagram and verify whether or not there is a common connector between the following:
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 2A
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 1A
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 1B
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 3K
•  MAIN 200 A fuse—Front body control module (FBCM) terminal 3L
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.
•  If the fuse is damaged:
―  Replace the fuse.
•  If the fuse is normal:
―  Refer to the wiring diagram and verify whether or not there is a common connector between the following:
•  Battery positive terminal—Front body control module (FBCM) terminal 2A
•  Battery positive terminal—Front body control module (FBCM) terminal 1A
•  Battery positive terminal—Front body control module (FBCM) terminal 1B
•  Battery positive terminal—Front body control module (FBCM) terminal 3K
•  Battery positive terminal—Front body control module (FBCM) terminal 3L
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 the next step.
7
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Always reconnect all disconnected connectors.
•  Clear the DTC for the front body control module (FBCM) using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 10 s or more.
•  Retrieve the front body control module (FBCM) DTCs using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the front body control module (FBCM).
Go to the next step.
No
Go to the next step.
8
VERIFY IF OTHER DTCs DISPLAYED
•  Are any other DTCs displayed?
Yes
Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.
No
DTC troubleshooting completed.