DTC U0127:00

id020200801300


Vehicles Without Advanced Keyless Entry And Push Button Start System

DESCRIPTION

Communication error with keyless receiver
DETECTION CONDITION
•  Communication error between instrument cluster and keyless receiver.
POSSIBLE CAUSE
•  Keyless receiver connector or terminals malfunction
•  BCM connector or terminals malfunction
•  Instrument cluster connector or terminals malfunction
•  Short to ground in wiring harness between the following terminals:
―  Keyless receiver terminal D—BCM terminal 4K—Instrument cluster terminal 2G
•  Short to power supply in wiring harness between the following terminals:
―  Keyless receiver terminal D—BCM terminal 4K—Instrument cluster terminal 2G
•  Open circuit in wiring harness between the following terminals:
―  Keyless receiver terminal D—BCM terminal 4K—Instrument cluster terminal 2G
•  Keyless receiver malfunction
•  BCM malfunction
•  Instrument cluster malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
INSPECT KEYLESS RECEIVER CONNECTOR AND TERMINALS
•  Switch the ignition to off.
•  Disconnect the negative battery cable.
•  Disconnect the keyless receiver connector.
•  Inspect the connector and terminals (corrosion, damage, pin disconnection).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
2
INSPECT BCM CONNECTOR AND TERMINALS
•  Disconnect the BCM connector.
•  Inspect the connector and terminals (corrosion, damage, pin disconnection).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
3
INSPECT INSTRUMENT CLUSTER CONNECTOR AND TERMINALS
•  Disconnect the instrument cluster connector.
•  Inspect the connector and terminals (corrosion, damage, pin disconnection).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
4
INSPECT WHEEL UNIT SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Keyless receiver, BCM and instrument cluster connectors are disconnected.
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground:
―  Keyless receiver terminal D
•  Is there continuity?
Yes
Repair or replace the wiring harness for a possible short to ground, then go to Step 9.
No
Go to the next step.
5
INSPECT WHEEL UNIT SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
•  Keyless receiver, BCM and instrument cluster connectors are disconnected.
•  Reconnect the negative battery cable.
•  Switch the ignition to ON.
•  Measure the voltage at the following terminal (wiring harness-side):
―  Keyless receiver terminal D
•  Is there any voltage?
Yes
Repair or replace the wiring harness for a possible short to power supply, then go to Step 9.
No
Go to the next step.
6
INSPECT WHEEL UNIT SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Keyless receiver, BCM and instrument cluster connectors are disconnected.
•  Switch the ignition to off.
•  Disconnect the negative battery cable.
•  Inspect for continuity between following terminals (wiring harness-side):
―  Keyless receiver terminal D—BCM terminal 4K
―  Keyless receiver terminal D—Instrument cluster terminal 2G
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to Step 9.
7
INSPECT KEYLESS RECEIVER
•  Reconnect the keyless receiver, BCM and instrument cluster connectors.
•  Reconnect the negative battery cable.
•  Inspect the keyless receiver.
•  Is there any malfunction?
Yes
Replace the keyless receiver, then go to Step 9.
(See KEYLESS RECEIVER REMOVAL/INSTALLATION.)
No
Go to the next step.
8
CONFIRM BCM DTC
•  Retrieve the BCM DTC using the M-MDS.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [BCM].)
No
Go to the next step.
9
VERIFY TROUBLESHOOTING COMPLETED
•  Make sure to reconnect the disconnected connectors.
•  Reconnect the negative battery cable.
•  Clear the DTC from the instrument cluster memory using the M-MDS.
•  Switch the ignition to ON and wait for 30 s or more.
•  Retrieve the TPMS DTC using the M-MDS.
•  Is the same DTC present?
Yes
Replace the instrument cluster, then go to the next step.
(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
No
Go to the next step.
10
VERIFY THAT NO OTHER DTCs ARE PRESENT
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See TIRE PRESSURE MONITORING SYSTEM (TPMS) ON-BOARD DIAGNOSIS.)
No
DTC troubleshooting completed.


Vehicles With Advanced Keyless Entry And Push Button Start System

DESCRIPTION

Communication error with keyless receiver
DETECTION CONDITION
•  Communication error between instrument cluster and keyless receiver.
POSSIBLE CAUSE
•  Keyless control module connector or terminals malfunction
•  BCM connector or terminals malfunction
•  Instrument cluster connector or terminals malfunction
•  Short to ground in wiring harness between the following terminals:
―  Keyless control module terminal 3X—BCM terminal 4K—Instrument cluster terminal 2G
•  Short to power supply in wiring harness between the following terminals:
―  Keyless control module terminal 3X—BCM terminal 4K—Instrument cluster terminal 2G
•  Open circuit in wiring harness between the following terminals:
―  Keyless control module terminal 3X—BCM terminal 4K—Instrument cluster terminal 2G
•  BCM malfunction
•  Keyless control module malfunction
•  Instrument cluster malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
INSPECT KEYLESS CONTROL MODULE CONNECTOR AND TERMINALS
•  Switch the ignition to off.
•  Disconnect the negative battery cable.
•  Disconnect the keyless control module connector.
•  Inspect the connector and terminals (corrosion, damage, pin disconnection).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
2
INSPECT BCM CONNECTOR AND TERMINALS
•  Disconnect the BCM connector.
•  Inspect the connector and terminals (corrosion, damage, pin disconnection).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
3
INSPECT INSTRUMENT CLUSTER CONNECTOR AND TERMINALS
•  Disconnect the instrument cluster connector.
•  Inspect the connector and terminals (corrosion, damage, pin disconnection).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
4
INSPECT WHEEL UNIT SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Keyless control module, BCM and instrument cluster connectors are disconnected.
•  Inspect for continuity between the following terminal (wiring harness-side) and body ground:
―  Keyless control module terminal 3X
•  Is there continuity?
Yes
Repair or replace the wiring harness for a possible short to ground, then go to Step 9.
No
Go to the next step.
5
INSPECT WHEEL UNIT SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY
•  Keyless control module, BCM and instrument cluster connectors are disconnected.
•  Reconnect the negative battery cable.
•  Switch the ignition to ON.
•  Measure the voltage at the following terminal (wiring harness-side):
―  Keyless control module terminal 3X
•  Is there any voltage?
Yes
Repair or replace the wiring harness for a possible short to power supply, then go to Step 9.
No
Go to the next step.
6
INSPECT WHEEL UNIT SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Keyless control module, BCM and instrument cluster connectors are disconnected.
•  Switch the ignition to off.
•  Disconnect the negative battery cable.
•  Inspect for continuity between following terminals (wiring harness-side):
―  Keyless control module terminal 3X—BCM terminal 4K
―  Keyless control module terminal 3X—Instrument cluster terminal 2G
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to Step 9.
7
INSPECT BCM
•  Reconnect the keyless control module, BCM and instrument cluster connectors.
•  Reconnect the negative battery cable.
•  Retrieve the BCM DTC using the M-MDS.
•  Are any DTCs display?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [BCM].)
No
Go to the next step.
8
INSPECT KEYLESS CONTROL MODULE
•  Measure the voltage at the following terminals (wiring harness-side):
―  Keyless control module terminal 3X
•  Is the voltage normal?
Yes
Go to the next step.
No
Replace the keyless control module, then go to the next step.
(See KEYLESS CONTROL MODULE REMOVAL/INSTALLATION.)
9
VERIFY TROUBLESHOOTING COMPLETED
•  Make sure to reconnect the disconnected connectors.
•  Reconnect the negative battery cable.
•  Clear the DTC from the instrument cluster memory using the M-MDS.
•  Switch the ignition to ON and wait for 30 s or more.
•  Retrieve the TPMS DTC using the M-MDS.
•  Is the same DTC present?
Yes
Replace the instrument cluster, then go to the next step.
(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
No
Go to the next step.
10
VERIFY THAT NO OTHER DTCs ARE PRESENT
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See TIRE PRESSURE MONITORING SYSTEM (TPMS) ON-BOARD DIAGNOSIS.)
No
DTC troubleshooting completed.