DTC Troubleshooting: C1421-14
DTC C1421-14: Main Torque Sensor Malfunction
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
DTC
Freeze Frame
C1421-14 Main Torque Sensor Malfunction
    

1.
DTC check:

DTC check
?1.
Turn the vehicle to the ON mode.

?2.
Clear the DTC with the HDS.


?3.
Turn the vehicle to the OFF (LOCK) mode, then start the engine.

?4.
Turn the steering wheel to left and right several times, and keep holding each direction for 10 seconds.

?5.
Check for DTCs with the HDS.
DTC Description
DTC
Freeze Frame
C1421-14 Main Torque Sensor Malfunction
    
C1423-14 Torque Sensor Power Source Circuit Malfunction
    

Is DTC C1421-14 indicated?

     
YES
     
     
     
Go to step 2.
     
YES
     
     
     
If DTC C1423-14 is also indicated, go to DTC C1423-14 troubleshooting.?
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.?
2.
Torque sensor performance check:

Torque sensor performance check
?1.
Turn the steering wheel to the right and left several times.

?2.
Check the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
TORQUE SENSOR MAIN
    

Is there less than about 0.3 V or more than about 4.8 V?

     
YES (Less than about 0.3 V)
     
     
     
Go to step 3.
     
YES (More than about 4.8 V)
     
     
     
Go to step 7.
     
NO
     
     
     
Check for loose terminals and poor connections at the EPS control unit connectors. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good EPS motor/control unit, then recheck. If the symptom/indication goes away with a known-good EPS motor/control unit, replace the original EPS motor/control unit.?
3.
Torque sensor check:

Torque sensor check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Torque sensor 6P connector

?3.
Connect terminals A and B with a jumper wire.
Terminal A
Torque sensor 6P connector (female terminals) No. 5:
Terminal B
Torque sensor 6P connector (female terminals) No. 2:


?4.
Turn the vehicle to the ON mode.

?5.
Check the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
TORQUE SENSOR MAIN
    

Is there about 5 V?

     
YES
     
     
     
     
NO
     
     
     
Go to step 4.
4.
Open wire check (T/S VDD line):

Open wire check (T/S VDD line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
EPS control unit connector C (4P)

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Torque sensor 6P connector: disconnected
 
EPS control unit connector C (4P): disconnected
Test point 1
Torque sensor 6P connector (female terminals) No. 5:
Test point 2
EPS control unit connector C (4P) No. 2


Is there continuity?

     
YES
     
     
     
The T/S VDD wire is OK. Go to step 5.
     
NO
     
     
     
Repair an open in the wire between the EPS control unit and the torque sensor.?
5.
Open wire check (TSM line):

Open wire check (TSM line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Torque sensor 6P connector: disconnected
 
EPS control unit connector C (4P): disconnected
Test point 1
Torque sensor 6P connector (female terminals) No. 2:
Test point 2
EPS control unit connector C (4P) No. 3


Is there continuity?

     
YES
     
     
     
The TSM wire is not open. Go to step 6.
     
NO
     
     
     
Repair an open in the wire between the EPS control unit and the torque sensor.?
6.
Shorted wire check (TSM line):

Shorted wire check (TSM line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Torque sensor 6P connector: disconnected
 
EPS control unit connector C (4P): disconnected
Test point 1
EPS control unit connector C (4P) No. 3
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short to ground in the wire between the EPS control unit and the torque sensor.?
     
NO
     
     
     
The TSM wire is OK. Check for loose terminals and poor connections at the EPS control unit connectors. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good EPS motor/control unit, then recheck. If the symptom/indication goes away with a known-good EPS motor/control unit, replace the original EPS motor/control unit.?
7.
EPS control unit check:

EPS control unit check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
EPS control unit connector C (4P)

?3.
Turn the vehicle to the ON mode.

?4.
Check the parameter(s) below with the HDS.
Signal
Current conditions
Values
Unit
TORQUE SENSOR MAIN
    

Is there about 5 V?

     
YES
     
     
     
Check for loose terminals and poor connections at the EPS control unit connectors. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good EPS motor/control unit, then recheck. If the symptom/indication goes away with a known-good EPS motor/control unit, replace the original EPS motor/control unit.?
     
NO
     
     
     
Go to step 8.
8.
Shorted wire check (TSM line to power):

Shorted wire check (TSM line to power)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Torque sensor 6P connector

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
EPS control unit connector C (4P): disconnected
 
Torque sensor 6P connector: disconnected
Test point 1
EPS control unit connector C (4P) No. 2
Test point 2
EPS control unit connector C (4P) No. 3

Is there continuity?

     
YES
     
     
     
Repair a short in the wire between the EPS control unit and the torque sensor.?
     
NO
     
     
     
Go to step 9.
9.
Open wire check (T/S GND line):

Open wire check (T/S GND line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
EPS control unit connector C (4P): disconnected
 
Torque sensor 6P connector: disconnected
Test point 1
EPS control unit connector C (4P) No. 1
Test point 2
Torque sensor 6P connector (female terminals) No. 3:


Is there continuity?

     
YES
     
     
     
The T/S GND wire is OK. Replace the steering gearbox.?
     
NO
     
     
     
Repair an open in the wire between the EPS control unit and the torque sensor.?