Citroen C5 MK3 1.6 THP 2012 Heater Blower not working

[Brian C5]

Any advice would be helpful.

Blower motor not working at any speed. I have checked fuse F11 40 amp and found it to be ok. Also checked wiring and connections/plugs at heater
control motor (resistor) for overheating, found no faults.
I have read various post that the most likely part having failed will be the heater control unit (resistor). I have removed this and wondered if anyone knows how to test this with a multimeter?

The Citroen part number for this is 6441S7 the cost is £147.

I can get a 3rd party one from GSF for £44 but not sure if it is of good quality. Has anyone had any experience with this part from GSF?

Last question can anyone recommend a member that has Lexia in the Glasgow area so I could get a full scan done rather than guessing what the fault could be?

Thanks in advance

Brian

.

[Paul-R]

Have you tried the shunt test as described in many of the threads?

[Brian C5]

What is the shunt test? Do you mean disconecting the battery and resetting the bsi?
If this is the shunt test I have not done this.

[GiveMeABreak]

No, that's a BSI reset:

BSI Reset / Battery Disconnect / Reconnect Procedure

He means bypassing the resistor (temporarily) to provide full power at start for the blower motor, as under normal conditions, these are generally started at a lower speed and increased gradually. If the motor bearings are starting to seize (water / rust), then often the lower power is insufficient to get the motor started. Applying full power from a direct feed can be enough to free it for a while - until the next time.

[Brian C5]

Thanks Marc will need to identify what wires do what.

[Paul-R]

Thanks Marc will need to identify what wires do what.

viewtopic.php?t=62347

[Brian C5]

Hello Marc

Well I ran two wires directly from battery terminals to the two wires coming out of the blower motor (red and green) and the blower motor did not work at all.
My next question is how is do you remove the blower motor?
It is very difficult to see any srews etc but I can feel one plastic lever that I have pulled on but motor still not shifting. Do you twist the motor and if so is it clockwise or anticlock wise?

Any help would be great as it is very difficult to drive the car with the windows steaming up all the time!!!!!

Thanks in advance
Brian

[GiveMeABreak]

This image is for a left hand drive, so ignore the pedals shown (and be glad you actually have a RHD - as it otherwise would involve removing the accelerator pedal assemble and knee airbags!).

Disconnect the air blower (12) connector ( as "e").
Press the tongue ( as "c"); Turn the air blower (12) clockwise to disengage it from its retaining lugs (In the direction of the arrow "d").
Release the soundproofing under the fascia panel and around the air blower (12).
Remove the air blower (12).

[Brian C5]

Many thanks this is a great help.

[Paul-R]

Well I ran two wires directly from battery terminals to the two wires coming out of the blower motor (red and green) and the blower motor did not work at all.

That's not the way to test as the motor is on the "earthy" side of the control unit. Connecting up the wires as you probably did would simply connect the earth of the battery to the earth connection in the plug and the positive to the "hot" side of the motor wire in the plug. You must have connected it like this as if you had tried the other way then there would have been a big spark as you effectively connect the battery positive to earth!

Connecting a link across the two thick wires is the best way to see if the motor works. If you're suspicious of the earth connection in the plug then connect the thick wire that ISN'T green (the red I think you said) directly to an earth point. If you have a suitable multimeter then you could measure the voltage on the red wire while the engine is running to see if it registers 12v - 14v.

Note that the motor won't run anyway unless the engine is running. Simply moving the ignition key to the ignition position isn't enough.

[Brian C5]

Hello Paul-R

Thanks for the info on how to check the motor properly. Today I attempted to remove the motor using the great info provided by Marc. I bent back the plastic locking tab and rotated the motor clockwise then decided to put in back into postion until I tried one more thing
I got a hammer and hit the motor casing with the rubber handle end as not to cause any damage to anything. The idea was to shock the motor which in turn might unstick the possible seized shaft.
I put the key in the ignition and started the engine and the blower motor burst into life!!!!!!
At the moment I have been using car and everything is working as it should but I know this might not last. The car had been standing for two weeks outside in the very wet and damp Scottish weather when this fault showed up on its first start up.
Never had a car before that a heater motor could seize up with only 35k on it.

Thanks for everyone that helped me on this topic and if it happens again (probably will) I now know how to test it properly and remove it if required.

Brian

[Paul-R]

If you go back and read some of the (many!) posts on this subject you'll see that it is theorised that the motor gets difficult to start up due to condensation on the shaft causing the bearings , in turn, to grip tighter on the shaft. This then means that extra current is needed to spin the motor up and the system then shuts down as a preventative measure.

The shunt technique allows full voltage to be applied to the motor which breaks the stiction and then often allows the motor to spin up in a normal soft start without tripping the system again. My car has been like this for several years.

What you have probably done is to shock the motor with your hammer to break this stiction. It's a shame you didn't try the shunt technique first though a this would have saved you the hassle of trying to remove the motor.

[Brian C5]

Thanks Paul will do it your way next time. I tried to find various posts on this subject and others but I don't seem to have much luck with it. Not sure if I am doing it right!!!!
Regards
Brian