Cabin blower motor stuck on full

[chrisr]

Thanks Puggy,
I will try that and let you know.
Cheers.

[chrisr]

Hi,
the blower worked last night so couldn't try the key wiggle.
The blower worked again this morning but on a short journey this afternoon it didn't start.I wiggled the key but no joy.
The blower worked again on the return short journey and worked again on the way home from work.
Any thoughts any one?

[jasper5]

When your motor is actually working, is it still only working on full speed?

If it is only working on full speed, no matter how intermittent, the fault can only be the control module, because the control module is the only thing that controls the speed of the motor.

If when you have the motor working, all speeds are available, then the fault could be due to anything related to connection, wiring issues or a faulty motor.

There is a very simple test to check the module is working or not...when the motor is not working...get a test lamp, start the engine, switch on the blower, place the test lamp across the thick red and black wire terminals at the module connections, If the module is working properly, the light will light up, check both sets of red and black wires.If the module is faulty, you will have zero power to your test lamp at the red and black wires that go to the motor.If you have power to the motor wires out of the module, then the fault lies in the motor, or wiring to the motor.

Remember these checks should be done when the motor is NOT working.

If you want to test the motor itself before testing the module, remove the motor from its housing....only 3 screws hold it on...then being very careful not to touch the fan itself, place a wire to each connection direct to a battery, be very careful, if the fan works there will be a lot of force produced from the fan.

The module is located behind the centre console right at the back behind the black tray which fits below the glove box.

[chrisr]

Thanks jasper5,
a lot of info there.
The blower works normally and all speeds are selectable when it is working.
I will run the checks that you have described.
Many thanks.

[madbaggie28]

i had the problem not so long ago motor stuck on full and would not switch off mine is a 2002 lx in the haynes manual it says the blower control module is part of the motor assembly but not on mine it aint it is to the right hand side of the motor it has two green plugs going into it i got one from a breakers and put it on and it worked only cost £10 insted of the £55 the stealer wanted it is really easy to change too only takes five mins to do hope this helps

[frankmassey]

I am a newbie to this site with a 3.0 V6 Auto 1998 the blower sometimes worked and sometimes did'nt now it don't work at all. having looked at your replies you seem to have had lots of experience and wondered if you could advise on how I go about checking the control switch/module/blower, many thanks.

Now let me see.....how may of these have I changed? Oh! sod it, too many to count.

too many 406 modules to count?

Now lets see, in the past 12 months I've had to fix a burnt out motor wire on all three 406s I've had my hands on, and in the last 2 years I bet there's been about another 10+ on this forum.

[jasper5]

Basically, the best thing to do is, firstly, get a test lamp of some sort, start the engine....the heater motor only works with the engine running...put your test lamp to the motor wires, if the lamp lights, the problem is either the motor or as mjb says, the burnt wire.

If the test lamp doesn't light, the fault should lie in the module or the wiring going to the module, Connect the test lamp to the module wires, power going in but nothing out, means the module is faulty.No power going in, means there is a fault in the wiring to the module, ignition switch etc.

[mjb]

nah I can tell you exactly what it is - it's the high current power connection to the blower burnt out.

The easy fix is to just hop on ebay and buy a new blower fan. When it comes, pull the soundproofing from under the passenger footwell, unplug the blower multi-plug (this will be incredibly stiff), unclip the wires from around the blower, then it's 3 philips screws to pull it out. Just put the new one and reverse everything you've done. You'll notice the old blower will have a thick red wire going into it, and if you look at the spade connector you'll see it's burnt

If you're competent with a soldering iron, it's possible to simply file down the spade back to the metal then put a new connector on and solder it up well, but you should be able to pick up a new blower for about £25

Nearly all D8s go wrong in this way, especially round xmas. I'm shocked we've only had the two this year - there were about 8 on here last year

[jasper5]

You never test anything before you buy a replacement part?

[mjb]

OK fair enough. Quick test then:

stick the ignition on
put the fan on manual onto a medium setting
get under the passenger footwell
remove the soundproofing or tape it out of the way
locate the big thick red wire on its own going into the blower
hold it away from the connector and wiggle
if it sparks or has any effect on the fan, it's as I described earlier.

[chrisr]

Success!
I have not had my blower working for most of Christmas and the new year and also the past week of sub zero temperatures going to work and back.
Not the best!
I have just got mine working.
I checked the thick red wire and spade as suggested but this was in perfect condition.
I unplugged the big block connector at the front with the ignition on and fan selected on and it started working when I unplugged it.
I plugged it in again and it is now working fine.
I will keep my now warm fingers crossed and hope that it continues working.
Many thanks for all the posts :