Code No. C1531: Abnormal motor terminal voltage

caution

If the EPS-ECU sets the diagnosis code No. C1531, 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.

The motor terminal voltage does not meet a predetermined voltage stored in the microcomputer, and the microcomputer determines that there is a problem in the motor terminal voltage.

Criteria for judging malfunction

The terminal voltage in the motor left and right is less than 0.2 V or more than 8.5 V.

DIAGNOSIS PROCEDURE

	Go to Step 2.

	Repair the damaged 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. 2 and the body earth.
OK: Continuity exists. (300 Ω or more)

(3)Measure the resistance between B-114-1 EPS-ECU connector terminal No. 1 and the body earth.
OK: Continuity exists. (300 Ω or more)

	Go to Step 3.

	Replace the steering gear & linkage assembly..

Recheck if the diagnosis code is set.

(1)Turn the electric motor switch to the "LOCK" (OFF) → "ON" position.

(2)Start the electric motor unit.

(3)Check if the diagnosis code No. C1531 is set as a current trouble.

	Replace EPS-ECU.

	Intermittent malfunction. (Refer to GROUP 00 - How to Cope with Intermittent Malfunction .)