Navigation System - Reverse Signal Circuit

Lexus IS250 IS220d GSE20 ALE20 - NAVIGATION

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK BACK-UP LIGHT

CHECK VEHICLE SIGNAL (DISPLAY CHECK MODE)

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

INSPECT MULTI-DISPLAY

INSPECT MULTI-DISPLAY

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

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

NAVIGATION SYSTEM - Reverse Signal Circuit

DESCRIPTION

The navigation ECU receives a reverse signal from the multi-display and information about the GPS antenna, and then adjusts vehicle position.


WIRING DIAGRAM

Navigation System - Reverse Signal Circuit. NAVIGATION. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

1.CHECK BACK-UP LIGHT

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 step 5
OK
3.CHECK HARNESS AND CONNECTOR (NAVIGATION ECU - MULTI-DISPLAY)
Navigation System - Reverse Signal Circuit. NAVIGATION. Lexus IS250 IS220d GSE20 ALE20

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 ConnectionConditionSpecified Condition
    REV2 - REVAlwaysBelow 1 Ω
    REV2 - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
4.INSPECT MULTI-DISPLAY
Navigation System - Reverse Signal Circuit. NAVIGATION. Lexus IS250 IS220d GSE20 ALE20

Reconnect the multi-display connector p1.

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

  • Standard voltage:
  • Tester ConnectionConditionSpecified condition
    REV - Body groundEngine switch is on (IG).
    Shift lever is moved to Reverse position.    		10 to 14 V
    REV - Body groundEngine switch is on (IG).
    Shift lever is moved to any position except Reverse.    		Below 1 V
NG
REPLACE MULTI-DISPLAY
OK
REPLACE NAVIGATION ECU
5.INSPECT MULTI-DISPLAY
Navigation System - Reverse Signal Circuit. NAVIGATION. Lexus IS250 IS220d GSE20 ALE20

Disconnect the multi-display connector J50.

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

  • Standard voltage:
  • Tester ConnectionConditionSpecified condition
    REV - Body groundEngine switch is on (IG).
    Shift lever is moved to Reverse position.    		10 to 14 V
    REV - Body groundEngine switch is on (IG).
    Shift lever is moved to any position except Reverse.    		Below 1 V
OK
REPLACE MULTI-DISPLAY
NG
6.CHECK HARNESS AND CONNECTOR (MULTI-DISPLAY - COWL SIDE J/B LH)
Navigation System - Reverse Signal Circuit. NAVIGATION. Lexus IS250 IS220d GSE20 ALE20

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 ConnectionConditionSpecified Condition
    REV - BackAlwaysBelow 1 Ω
    REV - Body groundAlways10 kΩ or higher
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
7.CHECK HARNESS AND CONNECTOR (JUNCTION CONNECTOR - COWL SIDE J/B LH)
Navigation System - Reverse Signal Circuit. NAVIGATION. Lexus IS250 IS220d GSE20 ALE20

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 ConnectionConditionSpecified condition
    BKUP - Body groundEngine switch is on (IG).
    Shift lever is moved to Reverse position.    		10 to 14 V
    BKUP - Body groundEngine switch is on (IG).
    Shift lever is moved to any position except Reverse.    		Below 1 V
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)