
FULL-AUTOMATIC AIR CONDITIONER –
Troubleshooting
55-47
Inspection procedure 9
Blower air amount cannot be changed.
Probable cause
If the blower does not operate in any mode other than HI setting, the cause is
probably a malfunction of the power transistor system.
D
Malfunction of power transistor
D
Malfunction of connector or harness
D
Malfunction of A/C-ECU
Measure at the power transistor connector B-37.
D
Blower switch position: LO
D
Connect the connector.
(1) Continuity between terminal (1) and body earth
OK: Continuity
(2) Voltage between terminal (2) and body earth (Ignition
switch: ON)
OK: System voltage – 2 V
(3) Voltage between terminal (4) and body earth (Ignition
switch: ON)
OK: Approx. 1.3 V
OK
Check the following connector:
B-37
NG
Repair
OK
Check the trouble symptom.
(1) NG
Check the harness between the power transistor and the body
earth, and repair if necessary.
(2) NG
Check the harness between the power transistor and the blower
motor, and repair if necessary.
(3) NG
Measure at the A/C-ECU connector B-04.
D
Blower switch position: LO
D
Connect the connector.
(1) Voltage between terminal (1) and body earth (Ignition
switch: ON)
OK: Approx. 7 V
(2) Voltage between terminal (2) and body earth (Ignition
switch: ON)
OK: Approx. 1.3 V
NG
Check the following connector:
B-04
NG
Repair
OK
Check the trouble symptom.
OK
Check the harness between the power transistor and the A/C-ECU.
NG
Repair
OK
Replace the power transistor.
NG
Replace the power transistor.
NG
Replace the A/C-ECU.
Inspection procedure 10
Air outlet port cannot be changed.
Probable cause
The cause is probably a malfunction of the air outlet port changeover signal
input system or output system. The MUT-
II
can be used to check the
diagnosis codes in order to check the cause of the problem for each separate
system.
D
Malfunction of air outlet changeover damper
potentiometer
D
Malfunction of air outlet changeover damper
motor
D
Malfunction of air outlet changeover damper
D
Malfunction of connector or harness
D
Malfunction of A/C-ECU
Can an operating sound be heard when the air outlet port
changeover switch is operated?
NO
Inspection procedure 15 (Refer to P.55-52.)
YES
MUT-
II
Self-Diag code
Is either code 32 or code 42 output?
YES
INSPECTION CHART FOR DIAGNOSIS CODES (Refer to
P.55-34.)
NO
Air outlet changeover damper check
NG
Repair
OK
Replace the A/C-ECU.