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DI-58
REAR SONAR SYSTEM
Revision: October 20052005 QX56
REAR SONAR SYSTEMPFP:28532
Component Parts and Harness Connector LocationEKS00BD2
1. Back-up lamp relay E45 2. Battery 3. Sonar buzzer M117
4. Rear sonar system OFF switch M116 5. Sonar control unit B56 6. Rear sonar sensor LH outer C102
7. Rear sonar sensor LH inner C103 8. Rear sonar sensor RH inner C104 9. Rear sonar sensor RH outer C105
10. A/T assembly F9
LKIA0693E
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REAR SONAR SYSTEM
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System DescriptionEKS00BD3
FUNCTION
With the ignition switch in the ON or START position, power is supplied
through 10A fuse [No. 12 , located in the fuse block (J/B)]
to sonar control unit terminal 8, and
through 10A fuse (No. 51, located in the IPDM E/R)
to back-up lamp relay terminals 1 and 3.
Ground is supplied
to sonar control unit terminal 6
through body grounds B7 and B19.
With the ignition switch in the ON or START position, and the transmission gear selector lever in the R posi-
tion, power is supplied
to sonar control unit terminal 5
from back-up lamp relay terminal 5.
With power and ground supplied, transmission gear selector lever in R position, and the rear sonar system
OFF switch ON, the rear sonar system will detect obstacles within 1.8 m (5.9 ft.) of the rear sonar sensors.
The vehicle operator is notified of obstacles by varied rate of tone from the sonar buzzer depending on dis-
tance of obstacle being sensed.
REAR SONAR SYSTEM OFF SWITCH
With power and ground supplied to the sonar control unit, transmission gear selector lever in R position, the
sonar system can be disabled and the sonar buzzer silenced by momentarily pressing the rear sonar system
OFF switch. The rear sonar system OFF indicator lamp will be illuminated in the rear sonar system OFF
switch.
To disable the rear sonar system, ground is supplied
to sonar control unit terminal 13
through rear sonar system OFF switch terminal 1
through rear sonar system OFF switch terminal 2
from body grounds M57, M61, and M79.
To light the rear sonar system OFF indicator, power is supplied
from sonar control unit terminal 4
to the rear sonar system OFF switch terminal 5.
Ground is supplied
to the rear sonar system OFF switch terminal 6
from body grounds M57, M61, and M79.
The rear sonar system and buzzer will be disabled and the rear sonar system OFF indicator will be illuminated
until the ignition switch is turned OFF. When the ignition switch is turned ON, the rear sonar system will be
enabled. Depressing the rear sonar system OFF switch momentarily will enable the rear sonar system also.
Enabling the rear sonar system will cause the rear sonar system OFF indicator to go out.
SONAR BUZZER
With power supplied to the sonar control unit and the transmission gear selector lever in R position, a station-
ary object that is at least 7.0 cm (2.8 in.) wide and 1.0 m (39.0 in.) tall and that is closer than 1.8 meters (5.9 ft.)
will be detected by the rear sonar sensors, causing the sonar buzzer to sound a tone. As the vehicle moves
closer to the object, the rate of the tone will increase. When the object is less than 25.0 cm (10 in.) from the
rear bumper, the tone will sound continuously.
Power is supplied
to sonar buzzer terminal +
from sonar control unit terminal 7.
Ground is supplied
to sonar buzzer terminal -
from sonar control unit terminal 3.
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DI-60
REAR SONAR SYSTEM
Revision: October 20052005 QX56
REAR SONAR SENSOR
With power and ground supplied to the rear sonar sensors, the sonar sensors transmit a 38.4 kHz ultrasonic
signal. This signal is reflected back to the sensor by objects large enough and close enough to be detected.
The rear sonar sensors measure the time from the transmitted signal to the time the signal is reflected back
and sends this information to the sonar control unit.
Power is supplied
to each rear sonar sensor terminal 1
from sonar control unit terminal 16.
Ground is supplied
to each rear sonar sensor terminal 3
from sonar control unit terminal 15.
Signal is supplied
to sonar control unit terminals 9, 10, 11 and 12.
from each rear sonar sensor terminal 2
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REAR SONAR SYSTEM
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Wiring Diagram — SONAR —EKS00BD4
WKWA2373E
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DI-62
REAR SONAR SYSTEM
Revision: October 20052005 QX56
WKWA1177E
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REAR SONAR SYSTEM
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Terminals And Reference Value For Sonar Control UnitEKS00BD5
How to Proceed With Trouble DiagnosisEKS00BD6
1. Confirm the symptom or customer complaint.
2. Understand operation description and function description. Refer to DI-59, "
System Description" .
3. Perform pre-diagnosis inspection. Refer to DI-64, "
Pre-diagnosis Inspection" .
4. Perform self-diagnosis. Refer to DI-64, "
Self-diagnosis Function" .
5. Perform the preliminary check. Refer to DI-66, "
Preliminary Check" .
6. Check symptom and repair or replace the cause of malfunction. Refer to DI-67, "
Symptom Chart" .
7. Does the rear sonar system operate properly? If so, go to 8. If not, go to 3.
8. Clear fault codes. Refer to DI-65, "
IDLING OR CLEARING FAULT CODES MODE" .
9. Inspection End.
TERMINAL
(COLOR)ITEMCONDITION
Reference value (V)
(Approx.) IGNITION
SWITCHOPERATION
3 (R) Sonar buzzer return ON — 0 - 12 (variable)
4 (BR/Y)Rear sonar system
OFF indicator outputONRear sonar system OFF
switch ON 0
OFF 12
5 (G/W) Reverse signal ONTransmission gear
selector leverR position 12
Transmission gear
selector leverNot R position 0
6 (B)Sonar control unit
ground —— 0
7 (L) Sonar buzzer drive
signalON — 12
8 (G/R)Sonar control unit
powerON — 12
9 (GR)Rear sonar sensor
signal - RH outerON
Rear sonar system OFF switch ON
Transmission gear selector lever in R
position
No obstacles12
10 (P)Rear sonar sensor
signal - LH outerON
Rear sonar system OFF switch ON
Transmission gear selector lever in R
position
No obstacles12
11 ( O )Rear sonar sensor
signal - LH innerON
Rear sonar system OFF switch ON
Transmission gear selector lever in R
position
Distance obstacles12
12 (LG)Rear sonar sensor
signal - RH innerON
Rear sonar system OFF switch ON
Transmission gear selector lever in R
position
Distance obstacles12
13 (LG)Rear sonar system
OFF switch signalONRear sonar system OFF
switchON 0
OFF 12
15 (Y)Rear sonar sensor
groundON — 0
16 (LG/B)Rear sonar sensor
powerON Ignition switch ON 12
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DI-64
REAR SONAR SYSTEM
Revision: October 20052005 QX56
Pre-diagnosis InspectionEKS00BD7
SENSOR STATUS CHECK
Check that the rear sonar sensor is properly aligned (bumper is not misaligned, no deformation in sensor
mounting area.
Check that snow, mud, or other foreign objects are not adhering to the rear sonar sensor.
Check that there is no deformation, scratches, or other damage to the rear sonar sensor.
Check that water has not accumulated in the rear sonar sensor.
CAUTION:
Use water, cotton swab, or other soft material for cleaning the sensor.
1. Check that there are no obstacles within each rear sonar sensor's detection range.
2. Check that there are no nearby ultrasound sources (such as the sounds of vehicle horns, motorcycle
engines, or truck air brakes).
3. Check that the vehicle is on a level surface.
Self-diagnosis FunctionEKS00BD8
There are four modes of self-diagnosis; entering diagnostics, requesting number of fault codes, requesting
fault codes, and idling or clearing fault codes. These steps must be followed in order. Self-diagnosis can be
manually exited by turning the ignition switch OFF, or selecting reverse gear. Self-diagnosis will exit unless a
fault code request occurs before a message is repeated five times without acknowledgement.
ENTERING DIAGNOSTICS MODE
1. Turn ignition switch ON. Rear sonar system OFF switch indica-
tor lamp illuminates for three seconds and then turns off.
2. Immediately push rear sonar system OFF switch ten times
within five seconds.
3. The sonar buzzer will sound once and the rear sonar system
OFF indicator will flash once.
REQUESTING NUMBER OF FAULT CODES MODE
1. While in diagnostic mode, push rear sonar system OFF switch
once.
2. The sonar buzzer will sound once.
3. Rear sonar system OFF indicator will flash once and sonar
buzzer will sound once for each fault code detected.
4. There will be a four second pause.
5. The number of fault codes will repeat five times then pause.
NOTE:
Self-diagnosis will exit unless requesting fault codes occurs
before five repeats ends.
Detection range
Rear sonar sensors Approx. 1.8 m (5.9 ft.) maximum
LKIA0389E
LKIA0388E
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REAR SONAR SYSTEM
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REQUESTING FAULT CODES MODE
1. While in "requesting number of fault codes" mode, push rear
sonar system OFF switch once.
2. The sonar buzzer will sound once.
3. Rear sonar system OFF indicator will flash and sonar buzzer will
sound the first digit of the fault code followed by a one second
pause.
4. Rear sonar system OFF indicator will flash and sonar buzzer will
sound the second digit of the fault code followed by a four sec-
ond pause.
5. The fault codes will repeat five times then pause.
NOTE:
Requesting fault codes will exit unless the fault code is acknowledged before five repeats ends.
The fault code is acknowledged by pushing the rear sonar system OFF switch once (the sonar buzzer
may sound). When all fault codes have been indicated, idle mode will be entered. See the following table
for fault code identification.
IDLING OR CLEARING FAULT CODES MODE
NOTE:
While in idle mode, self-diagnosis will automatically exit if no activity occurs for thirty seconds.
1. Push and hold rear sonar system OFF switch for three seconds
to reset time-out counter.
2. Push and hold rear sonar system OFF switch for three seconds
to clear codes.
Fault Code Malfunction Page Reference
1 1Rear sonar sensor LH
outer
Check harness for open
or short. If NG repair or
replace harness. If OK
replace sensor. Refer to
DI-68, "
REAR SONAR
SENSORS" . 1 2Rear sonar sensor LH
inner
1 3Rear sonar sensor RH
inner
1 4Rear sonar sensor RH
outer
2 1 Sonar buzzerDI-68, "
SONAR BUZZER"
2 2Rear sonar system OFF
indicatorDI-68, "
REAR SONAR
SYSTEM OFF INDICA-
TOR"
2 3Rear sonar system OFF
switchDI-68, "REAR SONAR
SYSTEM OFF SWITCH"
2 4 Sonar control unitReplace sonar control
unit. Refer to DI-68, "SONAR CONTROL
UNIT"
LKIA0390E
LKIA0391E