Reverse Signal Circuit: Wiring Diagram

WARNING: This page is about a different car, the 2006 Lexus IS 350 and 2006 Lexus IS 250. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Reverse Signal Circuit - Wiring Diagram

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

CHECK BACK-UP LIGHT
1. Move the shift lever to the R position and check if the back-up lights come on.
  OK: The back-up lights come on.
NG: GO TO LIGHTING SYSTEM

OK: Go to next step.

CHECK VEHICLE SIGNAL (DISPLAY CHECK MODE)

Enter the "Display Check" mode (Vehicle Signal Check Mode) (See DISPLAY CHECK MODE ).

Check that the display changes between ON and OFF according to the shift lever operation (P and R).

SHIFT LEVER POSITION DISPLAY

Shift Lever Position	Display
Reverse	ON
Except Reverse	OFF

HINT:

This display is updated once per seconds. As a result, it is normal for the display to lag behind the actual change in the switch.

Fig 2: Checking Vehicle Signal (Display Check Mode)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: GO TO STEP 5

OK: Go to next step.

CHECK HARNESS AND CONNECTOR (NAVIGATION ECU - MULTI-DISPLAY)

Disconnect multi-display connector p1 and navigation ECU connector p2.

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

STANDARD RESISTANCE

Tester connection	Condition	Specified condition
REV2 - REV	Always	Below 1 Ω
REV2 - Body ground	Always	10 kΩ or higher

Fig 3: Identifying Multi-Display Connector p1 And Navigation ECU Connector p2

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step.

INSPECT NAVIGATION ECU

Reconnect the multi-display connector p1.

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

STANDARD VOLTAGE

Tester connection	Condition	Specified condition
REV - Body ground	Engine switch is on (IG).	10 to 14 V
REV - Body ground	Shift lever is moved to Reverse position.	10 to 14 V
REV - Body ground	Engine switch is on (IG).	Below 1 V
REV - Body ground	Shift lever is moved to any position except Reverse.	Below 1 V

Fig 4: Reconnecting Multi-Display Connector p1

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE MULTI-DISPLAY

OK: REPLACE NAVIGATION ECU

INSPECT MULTI-DISPLAY

Disconnect the multi-display connector J50.

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

STANDARD VOLTAGE

Tester connection	Condition	Specified condition
REV - Body ground	Engine switch is on (IG).	10 to 14 V
REV - Body ground	Shift lever is moved to Reverse position.	10 to 14 V
REV - Body ground	Engine switch is on (IG).	Below 1 V
REV - Body ground	Shift lever is moved to any position except Reverse.	Below 1 V

Fig 5: Identifying Multi-Display Connector J50

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: REPLACE MULTI-DISPLAY

NG: Go to next step.

CHECK HARNESS AND CONNECTOR (MULTI-DISPLAY - COWL SIDE J/B LH)

Disconnect the multi-display connector J50 and cowl side J/B LH connector Q2.

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

STANDARD RESISTANCE

Tester connection	Condition	Specified condition
REV - Back	Always	Below 1 Ω
REV - Body ground	Always	10kΩ or higher

Fig 6: Identifying Multi-Display Connector J50 And Cowl Side J/B LH Connector Q2

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: Go to next step.

CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR - COWL SIDE J/B LH)

Disconnect the main body ECU LH (cowl side J/B LH) connector LJ.

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

STANDARD VOLTAGE

Tester connection	Condition	Specified condition
REV - Body ground	Engine switch is on (IG).	10 to 14 V
REV - Body ground	Shift lever is moved to Reverse position.	10 to 14 V
REV - Body ground	Engine switch is on (IG).	Below 1 V
REV - Body ground	Shift lever is moved to any position except Reverse.	Below 1 V

Fig 7: Identifying Terminal Of Main Body ECU LH (Cowl Side J/B LH) Connector LJ

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR

OK: REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)