Blower motor not running on 2001 1.9 TDi SE PD with Climatronic

[mephistophles]

Hi,
Recently bought this and drove it home in the evening, the screen wasn't clearing so I assumed that it was because I was unfamiliar with the controls and hadn't got them set right. I only had about 5 miles to go through town so I just opened the driver’s window instead.
In the cold light of day, once I'd read the destruction manual and turned stuff on properly, I discovered that the blower motor wasn't running at all
Read a variety of posts about this and tried a few things to figure it out, but to be honest I'm still no wiser as to what my problem is.
Here's what I have tried so far...
Checked fuse 25 in the fuse box on the driver’s side - OK.
Removed the fuse and checked the voltage there - 11.76v.
Removed the glove box and disconnected the blower fan, checked voltage - 11.76v (this voltage remains constant no matter what fan speed I select on the Climatronic?)
Removed blower fan and connected directly across the battery - runs fine.

Reconnected the blower fan then ran checked the codes on the Climatronic by turning ignition on then holding recirculate and ECON for two seconds – gave me error codes 511, 510, 313, 25b, 31d, 4f7, 4f8, 4f9, 4fa, 332, 538 & 318 (the head unit HAD been removed prior to this) and I reset them.

Did a self-diagnostic on the Climatronic system by holding recirculate and ECON, then turn ignition on, hold for two seconds more - heard all sorts of clicks and whirrs and after about 30s, it gave me two error codes - 4f9 & 4fa

Help!!! Which bit do I need to buy to get it working properly again or do you need more diags/information?
Thanks guys
Andy

[Flash2]

Hi Andy, welcome to the forum.

4F9 = fresh air blower
4FA = recirculation flap motor

The blower motor on the climatronic system has an electronic speed controller built in and it's common for the speed controller to fail even although the motor itself operates OK.

Removed the glove box and disconnected the blower fan, checked voltage - 11.76v

Mind you, when your doing voltage test on things like blower motors, it's best to measure the voltage when the component is plugged in and switched on. If you had a high resistance anywhere in the circuit it wont show up unless the circuit is under load. You need current flow to create voltage drop.

Jim.

[mephistophles]

Hi Jim
Thanks for the quick reply, so forgive me for being dense but do I need to buy a new blower motor, or the resistor that the link you've included leads me to?
OR
Do you need me to (try to (lol)) measure voltage with the motor plugged in, ignition on/engine running and the Climatronic fan speed at various settings? (I'm no electrician or mechanic - it's just what I remember from school....more years ago than I care to remember, lol)
I’m happy to do either.
I bought this car as my new job means I have to travel 80 miles a day just to get there and back and my old Rover is a proper petrol guzzler and costing me a fortune! I still have some juice in the Rover that I want use up but I hope to switch over my insurance and start using the Passat towards the end of theweek. I’d much rather do it with an efficient way of clearing the screen :-D
Thanks
Andy

[Flash2]

Hello again, Andy.
I didn't provide the link. The forum software does that.

Your system doesn't use a resistor. The blower speed is electronically controlled. AFAIK, the electronic speed controller is part of the blower motor, so you'd need a new motor.
Before you replace the motor though, I'd suggest redoing your voltage test with the motor connected, ignition on and blower speed set to full. Connect the voltmeter directly across the motor power supply and earth wires (black/blue - supply & brown - earth). Make sure you still have 12ish Volts. If not, you have a wiring fault.

If you do get 12V on the voltage test, there's still the possibility that the fault could be with the climatronic control unit. You would need diagnostic kit to check it further but on the few cars I've checked with your fault it has been the speed controller that has been faulty and not the control unit.

Jim.

[mephistophles]

Hi again

Ah, well THAT's annoying (Forum software adding links that is) lol. I'll give it a go tonight as I'm currently the aforementioned 40 miles away at work. Fingers crossed.

I'll let you know later so that the results are available for other users. Thanks for your help so far :-)

Cheers
Andy

[mephistophles]

Hi,

OK, on the 20VDC scale measuring across the terminals I read 0.01 with the motor connected, ignition on and full blower speed :-/ What's my next course of action?

Andy

Edit: it just struck me, should I be doing this test in series with the motor instead of across it ?

[caldirun]

Hi again

Ah, well THAT's annoying (Forum software adding links that is) lol. I'll give it a go tonight as I'm currently the aforementioned 40 miles away at work. Fingers crossed.

I'll let you know later so that the results are available for other users. Thanks for your help so far :-)

Cheers
Andy

If the fan runs with a direct supply it is ok, not sure if there is a relay between the climatronic and the motor,
there is not a speed controller in the motor, just brushes that are a very common problem.
Could be the brushes are contacting at times and not at other times (when you tried the direct supply)

[Flash2]

Hi,

OK, on the 20VDC scale measuring across the terminals I read 0.01 with the motor connected, ignition on and full blower speed :-/ What's my next course of action?

Andy

Edit: it just struck me, should I be doing this test in series with the motor instead of across it ?

Andy, voltage measurements are always taken across the component, not in series with it.

That voltage is very low. From that it looks like one of the wires is completely open circuit (or your meter wasn't connected properly). Since you had 12V when the motor was disconnected, that would suggest the fault is on the earth.
You can confirm that by carrying out these next measurements :

So you want to do basically the same test again (motor connected, ign on, full speed) only this time connect the red meter lead to the brown wire at the motor and the black meter lead to a clean part of the vehicle body.
If you get 12V now then the fault lies on the motor earth wire.

If the above test still shows no voltage then connect the black meter lead to the blue/black at the motor and connect the red meter lead to Battery + terminal.
If you get 12V now the fault is somewhere on the supply side of the motor.

Jim.

[Flash2]

there is not a speed controller in the motor, just brushes that are a very common problem.

I don't have Andy's car in front of me so can't be 100% sure, but does the the blower motor on a climatronic system not have a built in speed controller?
The normal blower that uses a resistor to control the speed has a 2 pin connector and the climatronic blower has a 6 pin connector ( and a built in speed controller)?

[mephistophles]

Hi guys,

Sorry this is taking a while but I have limited time when I get home. Just done both tests (for completeness)

motor connected, ign on, full speed, red meter lead to the brown wire at the motor and the black meter lead to a clean part of the vehicle body - Result = 11.8v (had to use a different meter with longer leads to be able to reach a clean bolt under the bonnet)

motor connected, ign on, full speed, black meter lead to the blue/black at the motor and connect the red meter lead to Battery + terminal - Result = 0v

So from what you say, it's the earth side of the motor?

Could it just be that part of the motor is duff which is causing that result?

BTW, not sure if you mean the connectors directly into the motor or something under the casing but I only have two wires into it a brown/yellow and a blue/black, also when I wired the motor straight across the battery, (about three times) I always held it "on its back" with the spindle running vertically and the fan bit at the top, worked straight away every time (and pretty powerful too)

Anwyay, what's next please?

Cheers
Andy