Toyota Venza: IG Power Supply Voltage Malfunction (C1551)

Toyota Venza Service Manual / Power Assist Systems / Power Steering System / IG Power Supply Voltage Malfunction (C1551)

DESCRIPTION

The power steering ECU distinguishes the ignition switch status as ON or off through the IG power source circuit.

DTC No.	DTC Detection Condition	Trouble Area
C1551	IG power source circuit malfunction inside ECU	ECU-IG No. 2 fuse IG power source circuit Power steering ECU

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

If the power steering ECU has been replaced with a new one, perform the rotation angle sensor initialization and torque sensor zero point calibration (See page ).

Inspection the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1.	READ VALUE USING TECHSTREAM (IG POWER SUPPLY)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / EMPS / Data List.

(f) Select the items "IG Power Supply" in the Data List and read the value displayed on the Techstream.

EMPS

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
IG Power Supply	ECU power source voltage/ Min.: 0 V Max.: 20.1531 V	11 to 14 V	Ignition switch ON

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

IG Power Supply

ECU power source voltage/

Min.: 0 V

Max.: 20.1531 V

11 to 14 V

Ignition switch ON

OK:

Normal condition value is displayed the Techstream.

REPLACE POWER STEERING ECU

2.	CHECK HARNESS AND CONNECTOR (BATTERY - POWER STEERING ECU)

(a) Disconnect the connectors from the power steering ECU.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
D20-6 (IG) - Body ground	Ignition switch ON	11 to 14 V

Standard Resistance:

Tester Connection	Condition	Specified Condition
D19-2 (PGND) - Body ground	Always	Below 1 Ω

Text in Illustration

*1	Front view of wire harness connector (to Power Steering ECU)

REPLACE POWER STEERING ECU

REPAIR OR REPLACE HARNESS OR CONNECTOR

Assist Map Number Un-Writing (C1581)

DESCRIPTION The power steering ECU stores this DTC when it determines that the assist map is not written in the ECU. HINT: The assist map is data written in the power steering ECU to control the ...

Motor Rotation Angle Sensor Malfunction (C1528)

DESCRIPTION The motor rotation angle sensor detects the motor rotation angle and sends this information to the power steering ECU. DTC No. DTC Detection Condition ...

Other materials about Toyota Venza:

Diagnosis System
DIAGNOSIS SYSTEM 1. ECUS OR SENSORS WHICH COMMUNICATE THROUGH CAN COMMUNICATION SYSTEM (a) CAN No. 1 Bus (1) ECM (2) Main body ECU (Driver side junction block) (3) Combination meter (4) Power steering ECU (5) Air conditioning amplifier*3 (6) Center air ...

Precaution
PRECAUTION 1. PRECAUTION FOR DISCONNECTING THE BATTERY CABLE NOTICE: When disconnecting the cable from the negative (-) battery terminal, initialize the following systems after the terminal is reconnected. System Name See Procedure ...

Removal
REMOVAL PROCEDURE 1. ALIGN FRONT WHEELS FACING STRAIGHT AHEAD 2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL NOTICE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See page ). 3. REMOVE FRONT WHEE ...