Lexus NX manuals

Lexus NX: On-vehicle Inspection

Lexus NX Service Manual / Vehicle Exterior / Lighting (ext) / Stop Light Control Relay / On-vehicle Inspection

ON-VEHICLE INSPECTION

PROCEDURE

1. INSPECT STOP LIGHT CONTROL ECU ASSEMBLY

(a) Disconnect the stop light control ECU assembly connector.

*a

Front view of wire harness connector

(to Stop Light Control ECU Assembly)

(b) Measure the voltage and resistance on the wire harness side connector according to the value (s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

A3-4 (ESS1) - A3-8 (GND)

Power switch on (IG)

11 to 14 V

A3-6 (+B) - A3-8 (GND)

Power switch off

11 to 14 V

A3-9 (ACC) - A3-8 (GND)

Power switch on (IG)

11 to 14 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

A3-8 (GND) - Body ground

Always

Below 1 Ω

If the result is not as specified, repair or replace the wire harness or connector.

(c) Reconnect the stop light control ECU assembly connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

A3-1 (OUT) - A3-8 (GND)

Brake pedal not depressed → pressed

Below 0 to 1.5 V → 7.5 to 14 V

A3-5 (STP) - A3-8 (GND)

Brake pedal not depressed → pressed

Below 0 to 1.5 V → 7.5 to 14 V

If the result is not as specified, replace the stop light control ECU assembly.

*a

Component with harness connected

(Stop Light Control ECU Assembly)

READ NEXT:

 Removal

REMOVAL PROCEDURE 1. REMOVE DOOR SCUFF PLATE ASSEMBLY LH Click here 2. REMOVE COWL SIDE TRIM BOARD LH Click here 3. REMOVE INSTRUMENT SIDE PANEL LH Click here 4. REMOVE NO. 1 INSTRUMENT

 Installation

INSTALLATION PROCEDURE 1. INSTALL STOP LIGHT CONTROL ECU ASSEMBLY (a) Attach the clamp to install the stop light control ECU assembly. (b) Connect the connector. 2. INSTALL LOWER NO. 1 INSTRUMENT PANE

 Stop Light Switch

SEE MORE:

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DESCRIPTION There may be an open circuit in one of the CAN main bus wire and/or a central gateway ECU (network gateway ECU) branch wire when the resistance between terminals 18 (CA4H) and 17 (CA4L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher. Symptom Trouble Area Res

 Data List / Active Test

DATA LIST / ACTIVE TEST DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be dis

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