Lexus RX300 (MCU15). Manual - part 378

I18203

Display 
check screen switch

Horizontal line 
check screen switch

DI–742

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DIAGNOSTICS

LEXUS NAVIGATION SYSTEM

LEXUS RX300   (RM785E)

(c)

TOUCH SWITCH CHECK MODE SCREEN

(1)

Operating condition is checked line by line in the Touch Switch Check Mode screen.

(2)

Check Line:
Lines are displayed by using infrared beams in this screen.
Once a beam is blocked off by touching the screen with a fingertip, the blocked part of the line
is deleted.

(3)

Horizontal Line Check Screen Switch:
Pressing this switch activates a screen in which beams of horizontal lines are checked.

(4)

Display Check Mode Switch
Pressing this switch activates the Display Check Mode screen.

I15462

Display
check screen switch

Press point

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DIAGNOSTICS

LEXUS NAVIGATION SYSTEM

DI–743

LEXUS RX300   (RM785E)

(d)

TOUCH POINT CHECK MODE SCREEN

(1)

In this screen, the position detected by the pressure sensing touch switch is checked.

(2)

Press point:
The detected point is indicated by a cross–hair cursor.

(3)

Display Check Screen Switch
Pressing this switch activates the Display Check Mode screen.

I15461

Display 
check screen switch

DI–744

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DIAGNOSTICS

LEXUS NAVIGATION SYSTEM

LEXUS RX300   (RM785E)

(e)

VEHICLE SIGNAL CHECK MODE SCREEN

(1)

Status of the Vehicle Signal which has been loaded into the display is checked in this screen.

(2)

Signal             Description
Battery: Displays battery voltage in V.
IG: Displays ON or OFF of the ignition switch.
PKB: Displays ON (applied) or OFF (released) of the parking brake.
SPEED: Displays the vehicle speed in km/h.
TAIL: Displays ON or OFF of the tail light switch.

(3)

Display Check Screen Switch
Pressing this switch activates the Display Check Mode screen.

DI27Z–06

Physical address

Logical address

Meaning

Three–digit code (shown in hexadecimal) which is given to each component comprising the 
AVC – LAN
Corresponding to the function, individual symbols are specified..

Two–digit code (shown in hexadecimal) which is given to each function comprising the inner system
of the AVC – LAN.

Physical address: 110 Multi display

Diagnosis item

Panel Switch 
Error

Touch Switch 
Error

Diagnosis content

Countermeasure and
inspected parts

Error in panel switch input part is de-
tected. 
(Error in switch control part, or inter-
nal communication error with switch
control part is detected.)

Error in touch switch sensor is de-
tected. 

D Inspect all switches on touch
switch test screen in display check
mode. If any of lines and point does
not react, replace multi–display as-
sembly.
D If all switches function without
problem, observe them for a while.

D Inspect all touch switches on
touch switch test screen in display
check mode. If any of lines does
not react, replace multi–display as-
sembly.
D If all of vertical and horizontal
lines react normally, observe them
for a while.

Logical address

21 *1
(Switch)

Replace multi–display assembly.

21
(Switch)

34
(Front passenger 
monitor)

DTC

11

10

Error in power supply system for
picture circuit (abnormal voltage) is
detected.

Error in Picture 
Circuit

10

Decline in power output from in-
verter circuit for backlight.

Backlight Error 
(No current)

Replace multi–display assembly.

34
(Front passenger 
monitor)

11

Excess power output from inverter
circuit for backlight.

Replace multi–display assembly.

34
(Front passenger 
monitor)

12

Backlight Error 
(Excess 
current)

Abnormal condition of ROM is de-
tected.

Replace multi–display assembly.

01
(Communication 
control)

21

ROM Error

Abnormal condition of RAM is de-
tected.

Replace multi–display assembly.

01
(Communication 
control)

22

RAM Error

Terms

*1: Check if the operation in Touch Point Check or Touch Switch Check screen is normal. If it operates without any
problem, see how things go for a while. 
Although this code is defined as Panel Switch Error, there are touch switches only on the display. If the internal com-
munication is erroneous, however, this code is stored.

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DIAGNOSTICS

LEXUS NAVIGATION SYSTEM

DI–745

LEXUS RX300   (RM785E)

DIAGNOSTIC TROUBLE CODE CHART