Code No. C1533: Motor overcurrent
Code No. C1534: Excessively low motor current







caution
  • If the EPS-ECU sets the diagnosis code No. C1533 or C1534, diagnose the CAN bus lines. If there is any fault in the CAN bus lines, an incorrect diagnosis code may be set.
  • Before replacing ECU, ensure that the communication circuit is normal.

DIAGNOSIS CODE SET CONDITIONS



Code No. C1533
  • The motor current detected by the microcomputer exceeds the limit value, and the microcomputer determines that a problem has occurred with the motor current.
Code No. C1534
  • The microcomputer outputs the indicator current exceeding the specified value, the detected motor current is less than the limit value, and the microcomputer determines that a problem has occurred with the motor current.

CRITERIA FOR JUDGING MALFUNCTION


Code No. C1533
  • The microcomputer indicator current exceeds 34 A.
Code No. C1534
  • The motor current measurement value is less than 2 A, and the microcomputer indicator current exceeds 4 A.

PROBABLE CAUSES



  • Defective harness wire(s) or connector(s)
  • Malfunction of the EPS-ECU
  • Motor malfunction

DIAGNOSIS PROCEDURE

STEP 1. Connector check: B-114-1 EPS-ECU connector

Q. Is the check result normal?
Go to Step 2.
Repair the damaged connector.

STEP 2. Measure the resistance at B-114-1 EPS-ECU connector.
(1)Disconnect the connector and measure at the wiring harness side.
(2) Measure the resistance between B-114-1 EPS-ECU connector terminal No. 1 and No. 2.
OK: 2 Ω or less

Q. Is the check result normal?
Go to Step 3.
Repair the wiring harness and connector. Or, replace the steering gear box & linkage assembly.

STEP 3. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1)Turn the electric motor switch to the "LOCK" (OFF) → "ON" position.
(2)With the electric motor unit started, turn the steering wheel to the left and right.
(3)Check if the diagnosis code No. C1533 or C1534 is set as a current trouble.

Q. Is diagnosis code C1533 or C1534 set?
Replace EPS-ECU.
Intermittent malfunction. (Refer to GROUP 00 - How to Cope with Intermittent Malfunction .)