Page 1933 of 2395
3 CHECK IN-VEHICLE SENSOR
Refer to HA-135.
OK or NG
OK©1. Replace auto amp.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
NG©1. Replace in-vehicle sensor.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
4 CHECK IN-VEHICLE SENSOR CIRCUIT BETWEEN AMBIENT SENSOR AND AUTO AMP. (LCU)
1. Disconnect auto amp. (LCU) harness connector.
2. Check circuit continuity between in-vehicle sensor harness terminal No. 1 and auto amp. (LCU) harness terminal No. 3.
RHA832H
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©1. Replace auto amp. (LCU).
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
NG©Repair harness or connector.
TROUBLE DIAGNOSES
In-vehicle Sensor Circuit (Cont'd)
HA-134
Page 1935 of 2395
obstructing the sunlight does not cause any change in the ATC
system operation. On the other hand, shortly after entering a long
tunnel, the system will recognize the change in sunload, and the
system will react accordingly.
SHA301FA
DIAGNOSTIC PROCEDURENBHA0048SYMPTOM: Sunload sensor circuit is open or shorted. (or
þ
is indicated on the display as a result of conducting Self-
diagnosis STEP 2.)
1 CHECK SUNLOAD SENSOR CIRCUIT BETWEEN SUNLOAD SENSOR AND BODY GROUND
Disconnect sunload sensor harness connector.
Do approx. 5 volts exist between sunload sensor harness terminal No. 1 and body ground?
RHA062G
YesorNo
Ye s©GO TO 2.
No©GO TO 4.
TROUBLE DIAGNOSES
Sunload Sensor Circuit (Cont'd)
HA-136
Page 1936 of 2395
2 CHECK SUNLOAD SENSOR CIRCUIT BETWEEN SUNLOAD SENSOR AND AUTO AMP. (LCU)
1. Disconnect auto amp. (LCU) harness connector.
2. Check circuit continuity between sunload sensor harness terminal No. 2 and auto amp. (LCU) harness terminal No. 11
or 9.
RHA833H
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 3.
NG©Repair harness or connector.
3 CHECK SUNLOAD SENSOR.
Refer to HA-138.
OK or NG
OK©1. Replace auto amp. (LCU).
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
NG©1. Replace sunload sensor.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
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TROUBLE DIAGNOSES
Sunload Sensor Circuit (Cont'd)
HA-137
Page 1937 of 2395
4 CHECK SUNLOAD SENSOR CIRCUIT BETWEEN SUNLOAD SENSOR AND AUTO AMP. (LCU)
1. Disconnect auto amp. (LCU) harness connector.
2. Check circuit continuity between sunload sensor harness terminal No. 1 and auto amp. (LCU) harness terminal No. 12
or 10.
RHA834H
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©1. Replace auto amp.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
NG©Repair harness or connector.
RHA835H
COMPONENT INSPECTIONNBHA0049Sunload SensorNBHA0049S01Measure voltage between auto amp. terminal 12 (10) and body
ground.
If NG, replace sunload sensor.
IWhen checking sunload sensor, select a place where sun
shines directly on it.
TROUBLE DIAGNOSES
Sunload Sensor Circuit (Cont'd)
HA-138
Page 1939 of 2395
RHA056GI
DIAGNOSTIC PROCEDURENBHA0106SYMPTOM: Intake sensor circuit is open or shorted. (or
þ
is indicated on the display as a result of conducting
Self-diagnosis STEP 2.)
1 CHECK INTAKE SENSOR CIRCUIT BETWEEN INTAKE SENSOR AND BODY GROUND
Disconnect intake sensor harness connector.
Do approx. 5 volts exist between intake sensor harness terminal No. 2 and body ground?
RHA495G
YesorNo
Ye s©GO TO 2.
No©GO TO 4.
2 CHECK INTAKE SENSOR CIRCUIT BETWEEN INTAKE SENSOR AND AUTO AMP. (LCU)
1. Disconnect auto amp. (LCU) harness connector.
2. Check circuit continuity between intake sensor harness terminal No. 2 and auto amp. (LCU) harness terminal No. 11 or
9.
RHA836H
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 3.
NG©Repair harness or connector.
TROUBLE DIAGNOSES
Intake Sensor Circuit (Cont'd)
HA-140
Page 1940 of 2395

3 CHECK INTAKE SENSOR
Refer to HA-139.
OK or NG
OK©1. Replace auto amp.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
NG©1. Replace intake sensor.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
4 CHECK INTAKE SENSOR CIRCUIT BETWEEN AMBIENT SENSOR AND AUTO AMP. (LCU)
1. Disconnect auto amp. (LCU) harness connector.
2. Check circuit continuity between intake sensor harness terminal No. 1 and auto amp. (LCU) harness terminal No. 1.
RHA837H
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©1. Replace auto amp.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
2.
Confirm that code No. 20 is displayed.
NG©Repair harness or connector.
Air Mix Door Motor PBR Circuit
DIAGNOSTIC PROCEDURENBHA0050For description of mode door motor and air mix door motor circuit,
refer to HA-84.
SYMPTOM: If PBR circuit is open or shorted. (þ
oris
indicated on the display as a result of conducting Self-diag-
nosis STEP 2.)
Perform diagnostic procedure for mode door motor and air
mix door motor. Refer to HA-78.
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TROUBLE DIAGNOSES
Intake Sensor Circuit (Cont'd)
HA-141
Page 1941 of 2395
RHA888H
Multiplex Communication Circuit
DIAGNOSTIC PROCEDURENBHA0118SYMPTOM:
IA/C system does not come on.
IA/C system can not controlled.
1 CHECK CIRCUIT CONTINUITY BETWEEN DISPLAY & NAVI CONTROL UNIT AND AUTO AMP.
Check circuit continuity between each terminal on Display & Navigation control unit and on auto amp.
RHA889H
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 2.
NG©1. Repair harness or connector.
2. Go to ªOPERATIONAL CHECKº, HA-66.
Confirm that A/C system is in good order.
2 CHECK MULTI-PLEX COMMUNICATION SIGNAL
Do approx. 3.5 volts exist between Display & NAVI control unit harness terminal Nos. 37, 38 and body ground?
RHA890H
YesorNo
Ye s©GO TO 3.
No©1. Replace auto amp.
2. Go to ªOPERATIONAL CHECKº, HA-66.
Confirm that A/C system is in good order.
TROUBLE DIAGNOSES
Multiplex Communication Circuit
HA-142
Page 1942 of 2395
3 CHECK MULTIPLEX COMMUNICATION SIGNAL
Do approx. 3.5 volts exist between auto amp. harness terminal No. 40 and body ground?
RHA891H
YesorNo
Ye s©INSPECTION END.
No©1. Replace Display & NAVI control unit.
2. Go to ªOPERATIONAL CHECKº, HA-66.
Confirm that A/C system is in good order.
GI
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LC
EC
FE
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PD
AX
SU
BR
ST
RS
BT
SC
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IDX
TROUBLE DIAGNOSES
Multiplex Communication Circuit (Cont'd)
HA-143