Climate control system

[ursus Junior Member Find all posts View Profile Close ursus]

Hi, guys,

I have a 2016 Prado Kakadu. The climate control system started misbehaving a couple of months ago. When I start the car, it doesn't come on automatically, as it used to be, and the display is only showing the time. Then, after some time, the directional indicator appears (that's the one that shows where the air is blowing), then I have to press the Auto button to start the system going. Even then, the fan has to be adjusted manually. Aircon is not cold enough when it's hot outside and vice versa, heating is not hot enough in cold weather.

I took the car to the Toyota dealer, and they said that the heating box needs to be replaced (pricey). Not that I don't trust them, but I just wanted to check if someone had experience with something like this. I like the car and want to keep it for at lest a few more years. My worry is not to get suckered into the endless repairs. Heat box now, then - oh, sorry, another thing also needs to be replaced and so on.

Any input would be greatly appreciated.

[Linedropper Lurker Find all posts View Profile Close Linedropper]

I have same model and and had a similar issue (climate control wouldn't start automatically after engine start) but my problem was no cold air out of the passenger (left side) air vents. You can view fault codes on the climate control display - videos on youtube for that part.

I identified which servo motor was faulty which for me was the upper motor on the side of the heater box, I got the numbers off it and ordered a motor from Fuhao Auto Parts on Ali Express after they confirmed correct motor. I then started dismantling the glove box assembly, other trim parts and some stuff deeper in behind the glovebox to get to the motor and it's screws and replaced it. Took about 1.5 hours for me from start to finish and I remember thinking I was lucky I didn't break anything. Main worry was removing the faulty motor from the side of the heater box as I had no idea how the motor shaft was fitted to the gears in there.

[ptommo59 Senior Member Find all posts View Profile Close ptommo59]

As Linedropper said most likely yours has a fault so is stopping part way through its normal start up process.

You can access the A/C DTCs to workout potential cause via the A/C control panel this way:

* Turn off the ignition

* Press Start Button once to ACC position and wait at least 5 seconds.

* Press Start Button again to IG ON position while holding down the "AUTO" and "Recirculation/Fresh" switches on the A/C control panel.

Continue holding down the switches until the display check screen appears (All A/C panel lights will illuminate and turn off consecutively 4 times at 1-second intervals).

When the indicator check is complete, the system will automatically enter DTC mode and display any detected fault codes on the display as a two digit number (00 is no faults)

If the DTCs are difficult to read because they change automatically, push the driver side "TEMP (UP)" switch to display the DTCs one at a time (press again to get the next on the list).

Write the DTC/s down so you can look up meaning via this link :Toyota-Club.Net - DTC - Climate control

The two digits shown on the display are the ones after the / above i.e. 46 would be B1446/46 Air Mix Damper Control Servo Motor Circuit (Driver Side) in the list. All codes without the / cannot be shown on the display so will need access to a Scantool to read.

Edit: your symptoms seem to link to the air mix servo flap on affected side/s not moving so potentially jammed/disconnected or servo failed. (So like code 41 and/or 46). These control how much air going through the cooler evaporator is redirected through the heater core to mix to required air temp e.g. max cool = 0, max hot = all, so if not moving temp will stay same).

[ursus Junior Member Find all posts View Profile Close ursus]

Thanks for the replies. Frankly, the technical detail here is way over my head. However, it confirmed my initial suspicion, that Toyota dealership cannot fix problems that are outside a basic service. I took the car to the local auto electrician in Randwick, and he diagnosed pretty much the same problem you guys are describing. Namely, servo motor on the driver's side was faulty. Plus, the battery was failing and the secondary battery was faulty. All was fixed in two days, for half the price, and I couldn't be happier with the result.

Thanks again for the advice.