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DTC C1514 Torque sensor power supply too low
 
 
 
 
caution
  • If there is any problem in the CAN bus lines, an incorrect DTC may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
  • Whenever ECU is replaced, ensure that the CAN bus lines are normal.
 
 
OPERATION
Power is supplied to the torque sensor from the electric power steering-ECU.
 
 
 
FUNCTION
To output the voltage based on the input torque from the torque sensor to the electric power steering-ECU, the voltage is supplied to the torque sensor.
 
 
 
TROUBLE JUDGMENT
Check Conditions
  • Torque sensor power supply ON
Judgment Criterion
  • The torque sensor power supply monitor voltage does not meet a predetermined voltage stored in the microcomputer, and the microcomputer determines that there is a problem in the torque sensor power supply voltage.
Fail Safe, Back Up Function
  • The electric power steering-ECU stops the motor control and illuminates the electric power steering warning symbol, then sets DTC C1514.
 
 
 
PROBABLE CAUSES
  • Malfunction of CAN bus line
  • Defective torque sensor of the steering column shaft assembly
  • Defective harness wire(s) or connector(s)
    • Short or open circuit between the electric power steering-ECU and the torque sensor or loose connector contact
    • Open circuit between the body ground and the electric power steering-ECU or loose connector contact
  • Malfunction of the electric power steering-ECU
 
 
 
 
DIAGNOSIS
STEP 1. Using scan tool MB991958, diagnose the CAN bus lines.
Use scan tool to diagnose the CAN bus lines.
Is the check result normal?
Go to Step 3.
Repair the CAN bus lines (Refer to GROUP 54C - Diagnosis/CAN Bus Diagnostics Table ). On completion, go to Step 2.
 
STEP 2. DTC recheck after resetting CAN bus lines
(1) Erase the DTC.
(2) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(3) Check if the DTC is set.
Is DTC C1514 set?
Go to Step 3.
This diagnosis is complete.
 
STEP 3. Check the following connector.
Check the connectors below for improper engagement, terminal damage or terminal drawn in the connector case.
  • C-145-1 and C-145 electric power steering-ECU connector
  • Body ground point
  • Torque sensor intermediate connector of the wiring harness for steering column shaft assembly (connection and appearance checks only)
Is the connectors and terminals in good condition?
Go to Step 4.
Repair the defective connector(s) or terminal(s). Then go to Step 9.
 
STEP 4. Wiring harness check
(1) Check the wiring harness between the C-145-1 electric power steering-ECU connector terminals No.21 or No.23 and the torque sensor for damage or other problem.
(2) Check the wiring harness between the C-145 electric power steering-ECU connector terminal No.12 and the body ground point for damage or other problem.
Is the wiring harness in good condition?
Go to Step 5.
Repair the defective wiring harness.Then go to Step 9.
 
STEP 5. Voltage measurement at the electric power steering-ECU connector
(1) The steering is in the neutral position.
(2) Measure the electric power steering-ECU voltage without disconnecting the connector (by backprobing).
(3) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(4) Measure the voltage between the C-145-1 electric power steering-ECU connector terminal No.21 and No.23.
OK: 5 ± 0.2 V
Is the check result normal?
Go to Step 6.
Go to Step 8.
 
STEP 6. Using scan tool MB991958, check the data list
(1) The steering is in the neutral position.
(2) Check the following data list .
  • Item No. 03: Torque sensor(power supply)
Is the check result normal?
Go to Step 9.
Go to Step 7.
 
STEP 7. Check whether the DTC is set again.
(1) Erase the DTC.
(2) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(3) Check if the DTC is set.
Is DTC C1514 set?
Replace the electric power steering-ECU (Refer to ).Then go to Step 8.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).
 
STEP 8. Check whether the DTC is set again.
(1) Erase the DTC.
(2) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(3) Check if the DTC is set.
Is DTC C1514 set?
Replace the steering column shaft assembly (Refer to ). Then go to Step 9.
This diagnosis is complete.
 
STEP 9. Check whether the DTC is set again.
(1) Erase the DTC.
(2) Turn the ignition switch from the "LOCK" (OFF) position to the "ON" position.
(3) Check if the DTC is set.
Is DTC C1514 set?
Return to Step 1.
This diagnosis is complete.