Heater Problems

[chris96]

Blows warm on p/side -cold on d/side ?

[Konrad C]

It sounds at best an air-lock, at worst a blocked heater radiator.

If you can reach the heater pipes in the engine bay, try bleeding the system by squeezing those pipes.

When I last changed the coolant for my Mk1, I squeezed the pipes before turning on the engine whilst topping up. The radiator cap is off. Then I would start the engine and squeeze all water pipes during warm-up. Then when the thermostat opens try and bleed a little more then replace the radiator cap. I top up the reservoir to a fraction over the 'Max' mark, then drive the vehicle.

The next day or when the car has the engine is cold, check and top up the coolant if necessary.

The heater control flaps on manual air-con is unified left and right, but cars with dual zone climate control have split sides. If your car has climate control then something could be wrong with the mechanism.

[Konrad C]

Your dual zone climate control is not working properly if the temperature settings for both sides are the same, and the not in 'dual' mode. If in dual setting then the obviously the passenger will have the higher setting. The 'dual' button should be illuminated when pressed, unless the bulb has blown.

You have started a new thread instead of replying to your existing one:-

http://www.toyotaownersclub.com/forums/topic/170693-2005-t-spirit/

[eastender lee]

I am having the same problem with cold air on drivers side and hot air on passangers side,  both sides set to high and dual mode is off,  it was fine until about 2 weeks ago, i checked the coolant and it was slightly low but still no change, nothing has been done to the car prior to this starting. How do i get the dual zone working properly again? or is there other options i can try?

Thanks in advance

Lee

[Milky Bar Kid 1001]

Same problem with my 2008 D4D. Ok till car gets up to full operating temperature (half way on gauge) then driver's side drops cooler whilst passenger side stays at fixed temperature (say 22°) on the heater controls. Have checked heater pipes on bulk head and they're both hot. Driver's side temperature adjustment motor flickers though so wondering if this maybe a possible cause(??)

[Konrad C]

There is a self test methods that should work. I have copied the instructions as follows - 

 

General information

AC control module incorporates self-diagnosis function.

AC control module trouble codes can be displayed on the control panel.

 

Accessing trouble codes

Ensure ignition switched OFF.

Depress and hold 'AUTO' switch [1].

Depress and hold 'recirculation/fresh air' switch [2].

Switch ignition ON.

AC/heater control panel LED's [3] and LCD [4] should illuminate 4 times.

System is now in diagnostic check mode.

Trouble codes are displayed by AC temperature/outside temperature display.

For example: Trouble code 21 displayed [5].

 

To display trouble codes individually:

Depress front defrost switch [6].

Depress front defrost switch [6] again to move to next trouble code.

Note trouble codes. Compare with trouble code table.

Switch ignition OFF. Rectify faults as necessary.

 

Erasing trouble codes

Ensure system in diagnostic check mode.

Depress and hold front defrost switch [6] and heated rear window switch [7] simultaneously.

Trouble codes erased.

Switch ignition OFF.

The AC control module fault memory can also be erased by removing fuse F10 (15A) from the engine bay fuse box for 20 seconds minimum.

Refit fuse.

 

Trouble code identification:

 

00     No fault found

11     In-car temperature sensor

12     Outside air temperature sensor

13     AC evaporator temperature sensor

14     Engine coolant temperature (ECT) sensor

21     AC sunlight sensor

22     AC compressor clutch lock sensor

23     AC refrigerant triple pressure switch

31     AC/heater air mix flap motor, potentiometer

33     AC/heater air direction motor, potentiometer

41     AC/heater air mix flap motor

43     AC/heater air direction motor

 

[Milky Bar Kid 1001]

Hi, just done the self diagnosis on the climate control unit and it came up with two codes, 21 & 24. What is code 24? Having difficulty in erasing the codes using the Front and Rear Defroster buttons, I'll pull the fuse out and re-run the test. Will the system erase the codes even though there are faults recorded? Now this is a problem if the is a permanent code on say engine etc when use or scanner at work. 

[Konrad C]

I found this - https://share.qclt.com/丰田Toyota RAV4 Repair Manual/Air Conditioning/Air Conditioning System (For Automatic Air Conditioning System)/0420015.pdf

The PDF refers to DTC No. B1424/24 as Solar Sensor Circuit (Driver Side), - Solar sensor - Wire harness between solar sensor and air conditioning amplifier - Air conditioning amplifier. 

Yes I just found this info and there may be more. Just a matter of searching.