POWER ASSIST SYSTEMS  POWER STEERING SYSTEM  C1551  IG Power Supply Voltage  


DESCRIPTION

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

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Return-to-normal Condition Note
C1551 IG Power Supply Voltage Open or short in IG power source circuit with ignition switch ON
·

ECU-IG NO. 5 fuse

·

IG power source circuit

·

Power steering ECU assembly


EPS warning light: Comes on After normal confirmation -

WIRING DIAGRAM

C113532
0.396,1.021 1.896,1.323 1.5,0.302 10 false from IG1 NO. 3 Relay 2.76,1.198 3.958,1.5 1.198,0.302 10 false ECU-IG NO. 5 4.458,1.031 4.885,1.333 0.427,0.302 10 false E40 4.531,0.833 4.958,1.135 0.427,0.302 10 false 1 4.823,1.042 5.25,1.344 0.427,0.302 10 false IG 4.813,2.135 5.24,2.438 0.427,0.302 10 false PGND 4.458,2.135 4.885,2.438 0.427,0.302 10 false A25 4.552,1.938 4.979,2.24 0.427,0.302 10 false 2 4.688,3 6.74,3.281 2.052,0.281 10 false Power Steering ECU Assembly

CAUTION / NOTICE / HINT

NOTICE:
·

If the power steering ECU assembly has been replaced, perform assist map writing and torque sensor zero point calibration.

Click hereSteering>POWER ASSIST SYSTEMS>POWER STEERING SYSTEM>CALIBRATION

·

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



PROCEDURE

1.READ VALUE USING GTS
a.

Turn the ignition switch off.


b.

Connect the GTS to the DLC3.


c.

Turn the ignition switch to ON.


d.

Turn the GTS on.


e.

Enter the following menus: Chassis / EMPS / Data List.


f.

Select the item "IG Power Supply" in the Data List and read the value displayed on the GTS.

Chassis > EMPS > Data List
Tester Display Measurement Item Range Normal Condition Diagnostic Note
IG Power Supply IG power source voltage Min.: 0.0000 V
Max.: 20.1531 V 		8 to 16 V Ignition switch ON
Chassis > EMPS > Data List
Tester Display
IG Power Supply
50003 142 11
OK:

The normal condition value is displayed on the GTS.



Result:
Proceed to
OK
NG



OK

REPLACE POWER STEERING ECU ASSEMBLY

Click hereSteering>POWER ASSIST SYSTEMS>POWER STEERING ECU>REMOVAL


NG

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

Disconnect the E40 and A25 power steering ECU assembly connectors.

C268777
1.146,1.302 1.448,1.542 0.302,0.24 4.188,1.5 4.5,1.708 0.313,0.208 1.698,2.063 1.958,1.854 false 6.063,2.427 5.802,1.958 false 1.177,1.333 1.49,1.531 0.313,0.198 10 false E40 0.26,0.198 0.573,0.396 0.313,0.198 10 false *a 1.521,2.031 1.833,2.229 0.313,0.198 10 false IG 4.229,1.521 4.688,1.719 0.458,0.198 10 false A25 5.938,2.479 6.552,2.677 0.615,0.198 10 false PGND
*a Front view of wire harness connector
(to Power Steering ECU Assembly) 		- -



b.

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

Standard Voltage:
Tester Connection Condition Specified Condition
E40-1 (IG) - Body ground Ignition switch ON 8 to 16 V



c.

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

Standard Resistance:
Tester Connection Condition Specified Condition
A25-2 (PGND) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

REPLACE POWER STEERING ECU ASSEMBLY

Click hereSteering>POWER ASSIST SYSTEMS>POWER STEERING ECU>REMOVAL


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR