DTC U1A4B:16 [BLIND SPOT MONITORING (BSM) SYSTEM]

id09021o065500

Caution
•  When replacing a blind spot monitoring (BSM) control module (RH) having any of the following part numbers, it is necessary to replace the blind spot monitoring (BSM) control module (LH) at the same time to perform the configuration normally.
―  DA6A-67Y80 A
―  DA6A-67Y80 B

Description

Blind spot monitoring (BSM) control module (RH) low power supply voltage input
Detection condition
•  Blind spot monitoring (BSM) control module (RH) power supply circuit voltage of 9 V or less is detected for 1 s or more with the ignition switched ON (engine off or on).
Fail-safe
•  Blind spot monitoring (BSM) system is stopped.
Possible cause
•  DTCs are stored in the PCM.
•  Battery malfunction
•  Generator malfunction
•  Blind spot monitoring (BSM) control module (RH) connector or terminal malfunction
•  Blind spot monitoring (BSM) control module (RH) power supply circuit malfunction
―  Short to ground in wiring harness between C/U IG1 15 A fuse and blind spot monitoring (BSM) control module (RH) terminal I
―  C/U IG1 15 A fuse malfunction
―  Open circuit in wiring harness between IG1 relay terminal C and blind spot monitoring (BSM) control module (RH) terminal I
•  Blind spot monitoring (BSM) control module (RH) malfunction

Diagnostic Procedure

Step

Inspection

Action
1
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 1.3, SKYACTIV-G 1.5].)
(See DTC TABLE [SKYACTIV-D 1.5].)
No
Go to the next step.
2
INSPECT BATTERY
•  Inspect the battery.
•  Is the battery normal?
Yes
Go to the next step.
No
Recharge or replace the battery, then go to Step 6.
(See BATTERY RECHARGING.)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 1.3, SKYACTIV-G 1.5].)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
3
INSPECT GENERATOR
•  Inspect the generator.
•  Is the generator normal?
Yes
Go to the next step.
No
Replace the generator, then go to Step 6.
(See GENERATOR REMOVAL/INSTALLATION [WITHOUT i-ELOOP (SKYACTIV-G 1.3, SKYACTIV-G 1.5)].)
(See GENERATOR REMOVAL/INSTALLATION [WITHOUT i-ELOOP (SKYACTIV-D 1.5)].)
(See GENERATOR REMOVAL/INSTALLATION [WITH i-ELOOP (SKYACTIV-G 1.3, SKYACTIV-G 1.5)].)
(See GENERATOR REMOVAL/INSTALLATION [WITH i-ELOOP (SKYACTIV-D 1.5)].)
4
INSPECT BLIND SPOT MONITORING (BSM) CONTROL MODULE (RH) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the negative battery cable.
•  Disconnect the blind spot monitoring (BSM) control module (RH) 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 6.
5
VERIFY BLIND SPOT MONITORING (BSM) CONTROL MODULE (RH) POWER SUPPLY VOLTAGE
•  Always reconnect all disconnected connectors.
•  Connect the negative battery cable.
•  Display the PID VPWR_R using the M-MDS.
•  Is the voltage B+?
Yes
Go to the next step.
No
Inspect the C/U IG1 15 A fuse.
•  If the fuse is blown:
―  Refer to the wiring diagram and verify whether or not there is a common connector between C/U IG1 15 A fuse and blind spot monitoring (BSM) control module (RH) terminal I.
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 IG1 relay and blind spot monitoring (BSM) control module (RH) terminal I.
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.
6
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Always reconnect all disconnected connectors.
•  Connect the negative battery cable.
•  Clear the DTC for the blind spot monitoring (BSM) control module using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 2.5 s or more.
•  Retrieve the blind spot monitoring (BSM) control module DTCs using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the blind spot monitoring (BSM) control module.
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 [BLIND SPOT MONITORING (BSM) SYSTEM].)
No
DTC troubleshooting completed.