2007 Mark X Zio - heater fan runs with ignition off

[nz_aj]

My Zio heater blower fan runs continuously, even with the ignition off, until the Battery goes flat.

It has climate control and all the controls will run via some sort of computer.

I can't find much online.  This model was made in Japan from 2007-2013.  It will likely have a lot of similarities with Auris / Avensis / Camry of similar years.

What I have seen is that the USA camry fan has a built in controller.  The assembly probably receives +12V directly from the Battery, as well as a control wire with a pulsing square form signal from the climate control.  The on board controller takes this signal and varies the speed of the fan. There is the potential for a fault with the fan or built in controller to cause the fan to run continuously.

Can anyone advise if this is how modern Toyota fans operate, typically what the wiring is like and if this fault is unusual?

[TomdeGuerre]

I can't give you any specific answer about your car but I was surprised to see (Google) this seems to be a problem with other cars too, on some Volvos and an Alfa. Opinions are divided as to whether it’s normal or caused by a faulty fan speed controller, see  http://www.volvoforums.org.uk/archive/index.php/t-76031.html

I don’t have climate control on my Auris but when the rotary fan speed switch is turned to its lowest setting the fan still runs. The only way to stop it is to press the Off button on the other main rotary controller which is for Temperature. I see you have an Off button next to the Auto selector: What happens if you press Off?

 

 

[nz_aj]

Pressing off, turning the fan speed know, changing vents, using auto, adjusting temperature, turning car on/off all have no effect. The fan speed stays on high.

I've checked the wiring to the fan, see photos. These appear to be ground, +12V and a signal wire (small red wire). I couldn't measure anything on the signal wire. I'm not certain how it works so can't be sure it's the problem, i.e. if it is an analog current signal, I wouldn't have picked that up.

Unplugging the fan enables the car to be started and driven normally. It may have been coincidence but when unplugged, the electric release for the rear hatch stopped working.

I've given up on it and booked car in with auto electrician. Known faults:

-heater fan not turning off

-remote window switches on drivers door not working

-cruise control turns on & off and sometimes says radar ready but pops up an error message before actually working

-rear hatch release sometimes not working

[nz_aj]

The problem with the fan turned out to be the controller on the back of the motor, specifically the transister. Refer photos. 

The window switches were fine, the electric windows just needed resetting. YouTube has a couple of videos showing how to reset modern toyota electric windows. Procedure is turn ignition on, lower drivers window and hold 3 seconds, raise & hold, lower, raise, repeat at drivers rear window, then passenger rear, then passenger front.

The cruise control throws up an error code says lost coms with distance module. Signal and power cables all test out OK, so it's probably a bad distance control module/computer, part # 88240-72010. A new replacement is NZ$920 ex Japan, so if anyone knows of a zio with cruise control being wrecked, I'd be interested.