DTC U3003:16 [CONNECTIVITY MASTER UNIT]


id0902n7106800

Description

Low ACC power supply voltage input to connectivity master unit (CMU)

Detection condition
•  The connectivity master unit (CMU) detects ACC power supply circuit voltage of 8.0 ± 0.8 V or less for 10 s or more with the ignition switched to ACC or ON (engine off or on).
Fail-safe function
Not applicable
Possible cause
•  DTCs are stored in the PCM.
•  Battery malfunction
•  Generator malfunction
•  Connectivity master unit (CMU) connector or terminal malfunction
•  Connectivity master unit (CMU) ACC power supply circuit malfunction
―  Short to ground in wiring harness between MIRROR 7.5 A fuse and connectivity master unit (CMU) terminal 2Q
―  MIRROR 7.5 A fuse malfunction
―  Open circuit in wiring harness between ACC relay and connectivity master unit (CMU) terminal 2Q
•  Connectivity master unit (CMU) malfunction

Diagnostic Procedure

Step

Inspection

Action

1
VERIFY PCM DTCs
•  Is a DTC displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
No
Go to the next step.
2
INSPECT BATTERY
•  Is the battery normal?
Yes
Go to the next step.
No
Recharge or replace the battery, then go to Step 6.
3
INSPECT GENERATOR
•  Is the generator normal?
Yes
Go to the next step.
No
Replace the generator, then go to Step 6.
4
INSPECT CONNECTIVITY MASTER UNIT (CMU) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the connectivity master unit (CMU) 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 CONNECTIVITY MASTER UNIT (CMU) ACC POWER SUPPLY VOLTAGE
•  Verify that the connectivity master unit (CMU) connector is disconnected.
•  Measure the voltage at connectivity master unit (CMU) terminal 2Q (wiring harness-side).
•  Is the voltage B+?
Yes
Go to the next step.
No
Inspect the MIRROR 7.5 A fuse.
•  If the fuse is blown:
―  Refer to the wiring diagram and verify if there is a common connector between MIRROR 7.5 A fuse and connectivity master unit (CMU) terminal 2Q.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
If there is no common connector:
•  Repair or replace the wiring harness which is shorted 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 if there is a common connector between ACC relay and connectivity master unit (CMU) terminal 2Q.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
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.
•  Clear the DTC for the connectivity master unit (CMU) using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 17 s or more.
•  Perform the DTC inspection for the connectivity master unit (CMU) using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the connectivity master unit (CMU).
Go to the next step.
No
Go to the next step.
7
VERIFY IF OTHER DTCs DISPLAYED
•  Are any other DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
No
DTC troubleshooting completed.