DTC U0401:68 [FRONT BODY CONTROL MODULE (FBCM)]

id0902p2010600

Description

Error signal received from PCM
Detection condition
•  Front body control module (FBCM) receives the error ECT sensor or ambient temperature sensor signals from the PCM for 5 s or more with the ignition switched ON (engine off or on).
Fail-safe function
Not applicable
Possible cause
•  ECT sensor malfunction
•  Ambient temperature sensor malfunction
•  PCM malfunction
•  Front body control module (FBCM) malfunction
System wiring diagram
Not applicable

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 5 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 7.
2
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 [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See DTC TABLE [SKYACTIV-D 1.5].)
(See DTC TABLE [SKYACTIV-D 2.2].)
(See DTC TABLE [MZR 1.6].)
No
Go to the next step.
3
INSPECT ECT SENSOR
•  Inspect the ECT sensor.
•  Is the ECT sensor normal?
Yes
Go to the next step.
No
Replace the ECT sensor, then go to Step 6.
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
(See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [MZR 1.6].)
4
INSPECT AMBIENT TEMPERATURE SENSOR
•  Inspect the ambient temperature sensor.
•  Is the ambient temperature sensor normal?
Yes
Go to the next step.
No
Replace the ambient temperature sensor, then go to Step 6.
(See AMBIENT TEMPERATURE SENSOR INSPECTION [MANUAL AIR CONDITIONER].)
(See AMBIENT TEMPERATURE SENSOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
5
PERFORM DTC INSPECTION AND VERIFY PCM MALFUNCTION
•  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 5 s or more.
•  Retrieve the front body control module (FBCM) DTCs using the M-MDS.
•  Is the same DTC displayed?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
(See PCM REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
(See PCM REMOVAL/INSTALLATION [MZR 1.6].)
No
Go to Step 7.
6
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  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 5 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.
7
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 [FRONT BODY CONTROL MODULE (FBCM)].)
No
DTC troubleshooting completed.