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Found this guide a while ago, thought id smash it up on here.

could be handy for those with digital climate controll problems.





TAKEN FROM: http://www.180sx.co.uk/resources/guides/jd...trol-diagnosis/



NOTE: There are 6 stages of diagnosis.


To enter stage/mode 1, the first point is to turn ignition to ‘on’, and within 5 seconds of doing this, you press and hold the “OFF” button on the heater control unit, for 5 seconds…


1st thing to happen should be that all the LEDS and display segments will illuminate.


If the elements dont light up at this point, the off switch is malfunctioning... if some of the other lights/segments dont light up, then theres a problem with either some of the bulbs, or the fluorescent display tube.


If you then press the 'up' arrowed button (hot), the display should then read '2', which indicates the 2nd stage of the diagnosis.


Pressing the 'down' arrow (cold) button will go from mode 2 - 1, and pressing the up arrow will go from mode 1 - 2.


Now unless the down arrow button isnt working, you should see the number 2.

This is mode/stage 2.

You may then see the number 20 displayed, which means that all external sensors are working correctly.

You may find it reads number 21, 22, 25, or 26... this indicates a malfunctioning or incorrectly wired sensor.


The codes are:

20 = All ok.

21 = Ambient Sensor.

22 = In-Vehicle Sensor.

25 = Sunload Sensor.

26 = PBR (Air-mix Door Position Sensor)


Pressing the 'up' arrow (hot) button again will move to mode 3 = number 3 is displayed.


Mode 3 again, like mode 2, will throw up error codes (if any present) or code 30 = all ok.

Error codes in mode 3 are for checking all the intake door motor and mode door position switches for error/malfunction, these are the possible error codes:


Note: Codes 31-35 refer to 'mode door' motor positions.

Codes 36-39 refer to 'Intake Door' motor positions.


30 = All ok.

31 = Vent.

32 = B/L.

33 = Foot.

34 = Foot/Def.

35 = Def.

36 = Fre.

38 = 20% Fre.

39 = Rec.


So, if your happy its all ok, you can press the "up" arrowed (Hot) button again, and now will be on to mode/stage 4... Phew!



Stage 4 involves the Control Unit going through various test patterns... and TBH I havent a clue what help this actually is, but...

Either the unit will display "41" and perform test pattern 41, then follow on, through patterns 42-46 automatically...

Or the 'Defrost' button is used to cycle through each mode/pattern.

(For this test and mode/stage 5 diagnostics, the engine must be running, for the A/C compressor to operate... unless you dont wish to test it).


Once you are happy with (or cant be bothered anymore with) this modes function... press the 'up' arrowed (hot) button again, to enter final stage of diagnosis... thank f**k!


So... Now the display should read '5' = Stage/Mode 5, which tests the Ambient Temp and In-Vehicle Temp sensors.


Press the 'DEF' button, and the temperature reading from each sensor will be displayed... 'DEF' pressed 1 time = Ambient? then 'DEF' pressed again = In-Car Sensor?... or, the other way around..?!


Now hit the button with the fan displayed on it.


You should then see ‘61′ on the display… this is the “Auxiliery Mechanism - Temperature Setting Trimmer” mode… and im guessing it calibrates the sensors for you.


Then hit either “Auto” button on the Unit, or turn ignition to ‘Off’, and this will END the diagnostics mode! Finally.


So, to confirm… you can use the ‘Hot’ and ‘Cold’ arrowed buttons to scroll through the different modes/stages of diagnosis, and you can select any stage, at any time, when in diagnosis mode.


To ‘Exit’ diagnosis mode at any time, either press the ‘Auto’ button, or turn the ignition to ‘Off’.

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