Honda Acura NSX 1991, Service Manual

Page: 900 / 1420

Troubleshouting
Self -diagnosis Circuit Check
The Automatic Climate Control System has a built-in self-diagnosis feature. To run it, turn the ignition switch ON and
turn the FAN switch to AUTO position. Wait for at least one minute on each TEMP display
Then, push both the AUTO and OFF buttons on the control unit at the same time. Any problems in circuits “A” through
listed below will be indicated by the respective indicator coming on.
The climate control unit does not memorize which self-diagnosis indicator lights comes on. If you turn the ignition switch
OFF, the indicator light memory will be lost.
B
A
C
I I F
I D E H
INDICATOR
COMPONENT WITH PROBLEM
POSSIBLE CAUSE Refer to PAGE
A M O D E
IN-CAR TEMPERATURE SENSOR
Open or short circuit
22-l 6
B
TEMPERATURE SENSOR Open or short circuit 22-l 8
C
SUNLIGHT SENSOR
Open or short circuit
22-20
D COOLANT TEMPERATURE SENSOR Open or short circuit 22-22
E
EVAPORATOR TEMPERATURE
SENSOR
Open or short circuit
22-24
F AIR MIX CONTROL MOTOR
Open or short circuit
Air mix door stuck
22-26
G O N
MODE CONTROL MOTOR
Open position signal circuit
Mode door stuck
22-30
H OFF (A/C)
RECIRCULATION CONTROL MOTOR Open position signal circuit 22-32
LED on
I
defroster
VENT DOOR CONTROL MOTOR
Open or short circuit
Vent door stuck
22-34
button
22-l 2
e