Airconditioning Diagnostic's

Hey i had the same problem and this helped me so give it a go it'll tell ya whats wrong with ur aircon it's puts ur
airconditiong into self-test diagnostic mode..

It is a six step process, although step six is not used for trouble diagnoses.
Step 1. Self-diagnostic test.
To enter diagnostic mode press the OFF button for more than five seconds within ten seconds of turning ignition
from ON to OFF.
Step 2. Sensor check.
Step 2 is selected by pressing HOT switch (the red triangle) while in diagnostic mode. The microcomputer detects whether
each sensor input signal is within correct parameters. The results are displayed on the screen.
If normal, a "20" is displayed.
If abnormal the failed sensor number is displayed. The sensor numbers are as follows:
20 - all is normal
21 - outside air sensor
22 - Inside air sensor
23 - Water temperature sensor
24 - Intake temperature sensor
25 - Sunload sensor
26 - PBR
27 - Refrigerant temperature sensor
This should tell you if any of your sensors are faulty.
Step 3. Mode door position check.
(This is probably not the cause of your problems but it is a nifty self check to play with). While in step 2, depress the
HOT button again. This will operate the the mode door actuator, and checks the wether the position detection switch is
operating. Again the results are displayed on the display.

If normal, a "30" is displayed.
If abnormal the number of the faulty mode is displayed as follows:

30: Normal
31: VENT
32: B/L (Bi level)
34: FOOT
Step 4: Actuator operation check.
By pressing the HOT button while in Step 3, you can actually send a signal to check the operation of the actuator manually.
It's a bit tricky and will take all day to write up how it works, so we will skip it!

Step 5: Sensor recognition check.
Press the HOT switch again and a "5" will be indicated in the display section. If you press the "AMB" button in this status,
the display will show the temperature sensed by each sensor. This will give you an indication also of which (if any) are
faulty. Temperatures will be displayed in the following order:

5 -> Outside air temp -> Inside air temp -> Suction temp -> Refrigerant temp

Obviously if any of these temps seem excessively different from actual temperatures you have a problem!

Step 6: Calibration
If you depress the fan switch during Step 5, you will go to Step 6 in which you can set the difference between
the indicated temperature and sensed temperature. I found this very useful because when I got my car I found
I had to set the inside temp to around 22 to feel comfortable even though I knew it was probably more like 20.
While in Step 6 press the HOT or COLD buttons to change the display by plus or minus 3 degrees in .5 degree increments.

This should get you back (click here)

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