Interior fans run all the time on high speed

[andy335touring]

After getting a flat Battery i jump started it off a lorry and got the wrong terminals on the lorry Battery meaning i gave my 2009 2.2 sr 24v by mistake.

This has fried some thing on the interior fans, they now only work on high speed and stay running even with the keys not in.

It was late/dark/raining when i got back so i've not had chance to have a look yet but would welcome any help for things to check or try when i have a look at it tomorrow.

Firstly i'll check the fuses then is there a fan relay that i can check ? If so where is it and how do i check it ?

Is there an ECU for the fan/aircon ?  

Thanks

[eygo]

find the relay and swap it out for another one of the same rating or greater they are rated in Amps

so you will see markings of 20a, 30a, 40a on the casing.

hope you haven't fried any ecu's i.e. alarm ,immobiliser engine major cost to replace them

if the relay doesn't stop the fan remove the switch.

[Mooly]

If you have aircon then the fan will be controlled electronically in order that it can run at many different speeds... and which isn't good from a failure point of view. I would suspect fried electronics although it would be worth disconnecting and reconnecting the Battery to reset everything as a first step. Leave it disconnected for a couple of minutes before reconnecting.

[Cjohnston1982]

Yes unplug the Battery. What I’ve done in the past is to turn on the ignition (do not start engine), unplug the Battery, turn the ignition key off then reconnect the Battery. Remember to leave the driver door open during the operation just in case.....

I found this to be the most effective way to reset an ECU in my previous cars.

[Konrad C]

You are lucky not to fry the electronics which could have been worse if you had reversed the polarity! I am surprised the fuses and fusible links did not blow.

If the reset method does not work, you need to locate the appropriate fuse, and pull that to stop the fan. I was going to say the heater switch, but if the fan is running with the key removed, then something seriously has melted causing a short. I would look at the ignition switch!   

You may need an auto electrician to confirm what may have gone wrong.
I never knew you could jump start from a lorry, or that the lorry may have 12v output. I have learnt a couple of new things.  

[furtula]

This should be helpful in locating the above said components, good luck.

http://www.autocats.ws/manual/toyota/auris_corolla_zze-zr-nde-ade/rm04f0e/index2.html

[andy335touring]

Thanks very much, very helpful suggestions ! 

I've had the Battery off over night charging so hopefully that will be enough time with out power to reset any ECU's ?

Touch wood it's just the fan that's gone wrong, i haven't noticed any thing else playing up.

 

 

[andy335touring]

As said earlier i charged the Battery over night, it was floating at 12.5-12.8v when i started looking at the car. 

I pulled every fuse in the engine bay fuse box and tested them with a multi-meter, all OK. The big multi fuse thing with the clear plastic top all i could do was remove the top and shine a torch down it and they all seemed OK.

Connected the Battery an the interior fan came on, bugger !

I pulled each fuse and relay in the engine bay and the fans kept running ?

Removed the glove box and pulled the plug on the fan. Tried to start it and it wouldn't, even with the charger on boost setting.

When you put the ignition on it pulls the Battery volts down to 9.5v.

So fan not running now so there's got to be another big drain/short ?

I'm going to try to get a new battery tomorrow just in case it's that, a bit hard as i only have the Auris.

The RAC struggled to get it going yesterday, it took him a booster pack and some jump leads from the van to get it going.

 

[andy335touring]

Battery coming tomorrow, RAC premium 5yr guarantee made by Varta, a bit pricey i'm in tough spot

 

[Mooly]

Things should be going pop (fusible links, fuses etc) if you can pull a healthy  Battery down to 9.5v across its terminals. Always worth turning headlights on (or pull the full beam stick) and see if the Battery holds up.

 

 

 

[andy335touring]

RAC fitted the Battery and it starts on its own now !

The other RAC bloke who came out to the brake down said he couldn't test the Battery but this bloke did and it had only got 16 amps cranking power out of the 700 ish amps it's supposed to have. This bloke said i'd most probably fried a body control ECU, aside from what i did to it he said Japanese cars are known for being sensitive to surges/sparks damaging ECU's when being jumped.

He recommended an auto electrician, the chap said it's not some thing they've come across before and to try the dealers. Spoke to a chap in the garage and he also drew a blank on the problem so now i've got the car booked in for a week today. My wallet is going to take a serous bashing but it's my fault so i've just got to get it done.

Many thanks for helping a newbie out, i'll keep this thread updated just for future reference when i know more.

[Mooly]

So the original Battery was totally shot. Its impossible to second guess the nature of a man made failure like this and the main dealer approach (as would any repair service) will be to swap  out the most likely suspects on a module basis. It will be interesting to know what the outcome is.

 

[mrpj]

23 hours ago, Mooly said:

the main dealer approach (as would any repair service) will be to swap  out the most likely suspects on a module basis.

I disagree, a proper diagnosis should be carried out before loading up the parts cannon in the hope that will fix the issue. That's what a proper garage, not any repair sevice, should do.

I agree that would be a main dealer approach though.

 

[andy335touring]

Just to update what happened, the dealer found that there's a fan speed controller built into the fan motor housing which was faulty.

The controller isn't available on it's own so i ended up replacing the fan motor.

At least it wasn't some £1000 plus VAT Ecu that i fried ! 

Thanks

[Cjohnston1982]

That’s good to hear. Could have been much worse. Hopefully your car will be back on the road soon 🚙 

[Mooly]

Yes, that is good news. Hope all is running well now :)