Lexus NX: PIG Power Supply Voltage (C1552,C1554)

DESCRIPTION

When a problem occurs in the power steering system, the power source relay circuit is shut off to stop the power assist.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

Warning Indicate

Return-to-normal Condition

Note

C1552

PIG Power Supply Voltage

PIG power source circuit malfunction inside ECU

  • EPS fuse
  • PIG power source circuit
  • ECU wire sub-assembly
  • Power steering ECU assembly

On

Power switch on (IG) again

-

C1554

Power Supply Relay Failure

Power source relay circuit malfunction

  • EPS fuse
  • PIG power source circuit
  • ECU wire sub-assembly
  • Power steering ECU assembly

On

Power switch on (IG) again

-

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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

Click here

HINT:

  • When DTC C1551 is detected together with DTCs C1552 and C1554, inspect and repair the trouble areas indicated by DTC C1551 first.
  • Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.

CHECK CONNECTOR CONNECTION CONDITION AND GROUND WIRE

(a) Check the connection condition of the ECU wire sub-assembly and power steering ECU assembly connectors.

OK:

The ECU wire sub-assembly and power steering ECU assembly connectors are securely connected.

(b) Check that the ground wire is securely installed with the bolt.

Click here

OK:

The ground wire is securely installed with the bolt.

NG

CONNECT CONNECTOR OR INSTALL GROUND WIRE

OK

2.

READ VALUE USING TECHSTREAM (PIG POWER SUPPLY)

(a) Turn the power switch off.

(b) Connect the Techstream to the DLC3.

(c) Turn the power switch on (IG).

(d) Turn the Techstream on.

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

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

Chassis > EMPS > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

PIG Power Supply

Power source voltage to active motor

Min.: 0.0000 V

Max.: 20.1531 V

Always: 9 to 16 V

-

Chassis > EMPS > Data List

Tester Display

PIG Power Supply

OK:

The normal condition value is displayed on the Techstream.

OK

CHECK INTERMITTENT PROBLEMS

NG

3.

CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - ECU WIRE SUB-ASSEMBLY)

(a) Disconnect the An1 ECU wire sub-assembly connector.

*a

Front view of wire harness connector

(to ECU Wire Sub-assembly)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

An1-1 (PIG) - Body ground

Always

9 to 16 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.

CHECK ECU WIRE SUB-ASSEMBLY

(a) Connect the An1 connector to the ECU wire sub-assembly.

*a

Front view of wire harness connector

(to Power Steering ECU Assembly)

(b) Disconnect the n1 power steering ECU assembly connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

n1-1 (PIG) - Body ground

Always

9 to 16 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

n1-2 (PGND) - Body ground

Always

Below 1 Ω

OK

REPLACE POWER STEERING ECU ASSEMBLY

NG

REPAIR OR REPLACE ECU WIRE SUB-ASSEMBLY

READ NEXT:

 Error in Matching of ECUs (C1567)

DESCRIPTION Based on the ECM signal, the power steering ECU assembly determines if the correct type of ECM is installed. DTC No. Detection Item DTC Detection Condition Trouble Area Warning

 Assist Map Number Un-Writing (C1581)

DESCRIPTION This DTC will be stored if the power steering ECU assembly determines that the assist map is not written in the ECU. DTC No. Detection Item DTC Detection Condition Trouble Area

 Assist Map Number Mismatch (C1582)

DESCRIPTION When an incorrect hybrid vehicle control ECU, incorrect skid control ECU or incorrect main body ECU is installed after the assist map has been written in the power steering ECU assembly, D

SEE MORE:

 Key-off Operation Function Operates even if Operating Conditions are not Satisfied

DESCRIPTION When the front doors are closed, each power window regulator motor assembly can control its power window operation for approximately 43 seconds after the power switch is turned from on (IG) to off by receiving operation permission signals from the main body ECU (multiplex network body

 Installation

INSTALLATION PROCEDURE 1. INSPECT COMPRESSOR OIL (a) When replacing the compressor assembly with motor with a new one, gradually discharge the inert gas from the service valve, and drain the following amount of oil from the new compressor assembly with motor before installation. Standard: (Oil c

© 2016-2024 Copyright www.lexunx.com