Opel Frontera UBS. Manual - part 1874

AIR CONDITIONING  1B–97

TROUBLESHOOTING WITH SELF-DIAGNOSIS FUNCTION

1. Overview of Self-Diagnosis Function

The self-diagnosis is implemented in 3 steps for each target. For detail of check procedure contained in
each step, refer to the relevant section of "Check Procedure by Failed Location" listed in the Self-
Diagnosis Operation Procedure.
For turning on the self-diagnosis function and switching of the check step, refer to the flow chart given
below. You can reset the self-diagnosis function by turning the ignition switch off or turning the DEF
switch on for 3 seconds.

2. Self-Diagnosis Operation Procedure

While holding both the Auto switch and the DEF switch on the
automatic heater/air conditioner panel, turn the IG off and then
on.

<Current trouble diagnosing function is turned on>

Does the A/C LED flash every 0.5 second interval?

Press the A/C switch once.

(The past trouble
diagnosing function will
be turned on.)

<Past trouble diagnosing function is turned on>

Does the A/C LED flashes every 0.5 seconds?

<Check of output equipment>

Does each output equipment functions normally according to

operation of the temperature setting lever?

Press the DEF switch for 3
seconds consecutively or turn on
and off the IG.

Failure on the

output equipment

or the harness.

Preparations
(1) Set the IG to the OFF mode.
(2) Apply 60W bulb light to the sun sensor.
(3) Set the temperature setting lever on the automatic heater/air

conditioner panel to the center position (25C).

(4) Set the fan switch on the same panel to the Auto position.

End of the self-diagnosis.

(The current trouble diagnosing function will be turned on
approximately in 10 seconds.)

YES

NO

YES

NO

NO

YES

Refer to *1.

Refer to *2.

1B–98 AIR CONDITIONING

*1. Displaying the Current Trouble Diagnosing Table

Start the engine while holding down both the Auto switch and the DEF switch on the control panel, and
the table will appear in approximately 10 seconds to the indicator lamp (LED) of the air conditioning
switch. Result of the diagnosis along the following 9 items will be shown one by one in 0.5 second
interval irrespective of presence or absence of a trouble for a given item. When the display 9 items is
completed, it is repeated with 3 seconds of interval in between. A failed item is indicated by flashing of
the LED that is repeated 3 times within 0.5 seconds. If a trouble is indicated, you can locate the failed
section by knowing when in the total sequence it has been displayed.

Items for Current Trouble Diagnosis

As shown above, display of result along nine items is repeated with 3-second interval in between.
Note 1: When checking the solar radiation sensor, apply sufficient light using a 60W bulb.

Otherwise, it can be diagnosed as failed.

Note 2: If the temperature setting lever is set on both ends (one set to 18°C, blue scale = Full cool and

the other to 31°C, red scale = Full hot), they can be diagnosed as failed.

Note 3: Likewise, the fan switch can be diagnosed as failed if set on both ends.

LED on

LED off

Indication for presence
of a trouble

Indication for normal state

0.5

0.5

0.5

3 seconds interval

ON

OFF

Display pattern

Failed part

Normal pattern

In car sensor

Ambient sensor

Sun sensor (Note 1)

Duct sensor

Temperature control lever (Note 2)

Fan switch (Note 3)

Mix actuator

Mode (blow port) control

Intake (fresh air/interior air switching) control

F01RX010

F01RY00008

AIR CONDITIONING  1B–99

*2. Displaying the Past Trouble Diagnosing Table

The past trouble diagnosis displays only the items on which trouble has recurred 16 times in the past.
If you press the air conditioning switch once while the current trouble diagnosis is taking place, display
of the past trouble diagnosis will appear on the indicator lamp (LED) of the air conditioning switch.
Results of the diagnosis along the following five items are displayed one by one in 0.5 second interval
irrespective of presence or absence of a trouble. A failed item is indicated by flashing of the LED that is
repeated 3 times within 0.5 seconds. You can locate the failed section by counting in what sequence it
has been displayed.

Items for Past Trouble Diagnosis

LED on

LED off

Indication for presence of a trouble

Indication for normal state

0.5

0.5

0.5

3 second interval

Display pattern

ON

OFF

Normal pattern

In car sensor

Ambient sensor

Sun sensor

Duct sensor

Mix actuator

Failed part

F01RX011

F01RY00007

*3. Check of Output Equipment

FAN

MIX

MODE
DOOR

INTAKE

DOOR

SET UP

TEMPERATURE

100

(%)

33.5

F/H

VENT

B/L

FOOT

D/F

DEF

REC

MIX

FRE

F/C

20

21

22

23

24

25

26

27

28

29

30

F/H

(%)

F/C

F01RY00001

1B–100 AIR CONDITIONING

Independent check of sensors

Replace the control unit.

Sensors

Allowable range

Check method

In car sensor

Ambient sensor

Sun sensor

Refer to the sensor resistance curve.

Refer to the sensor resistance curve.

100 ohms maximum in forward and 0.02 mA

minimum when exposed to 60W incandescent lamp.

Chart 1

Chart 2

Chart 3

Replace the harness and

connector.

Replace the sensors.

Check the related harness and

connector

Normal ?

Normal ?

NO

NO

YES

YES

INSPECTION BY FAILED LOCATION

Inspection of the Sensors

When the self-diagnosis function has determined that trouble is present on the sensors, check them
according to the following flow chart.

F01RY00005