Dual climate control heater matrix issue

[chambl01]

Hi Everyone, I have a 2003- 75 with a heater matrix issue. I have the dual climate control which all heating and speeds work perfectly. However, if I go to the 3rd bar or speed the fan starts making a flapping sound. If I speed up the fan, it gets louder and faster. If I reduce the speed it slows down. If I go back to two bars it stops completely until I press for more speed. I don't have a clue what it is. Has anyone had this and looked into it before. Everything otherwise works perfectly. Thank you .

[Devilish]

My guess is something stuck to a fan blade, bearing is shot, or the rotor blades are out of balance causing a rattle, whatever it is, you will have to pop the bumper off for a butchers.

[SD1too]

Originally Posted by Devilish

... you will have to pop the bumper off for a butchers.

I think he's talking about the heater blower Steve.

Simon

[chambl01]

Originally Posted by Devilish

My guess is something stuck to a fan blade, bearing is shot, or the rotor blades are out of balance causing a rattle, whatever it is, you will have to pop the bumper off for a butchers.

Thanks buddy but I'm referring to the heater blower fan inside the car.

[Dallas]

I thought you were going to say you had the dreaded blowing cold on passenger side problem for one moment, currently my issue.

Your issue could be leaves in the fan/blower motor, open all vents and go through all positions using the switches, the leaf or leaves generally blow out or get chewed up.

[Devilish]

Originally Posted by SD1too

I think he's talking about the heater blower Steve.

Simon

Meant pop the dash off LOL, (trebor told me to tell him to take the bumper off) and have a butchers in the vents, if lucky it will be a leaf. If it seems distant, lift the ECU out the way, and pop the pollen filter out and have a butchers. Difficult for a leaf to get past the filter, unless it is not seated correctly. If lucky it will not be the motor, don't like the way it matches the fan speed.

Would you say the flapping rate and volume increase is in synch with the fan speed (a bit like a lollipop stick taped to forks on a bicycle,) or is it just random flapping

[COLVERT]

Sounds like a leaf but very difficult to get a leaf in there.

Maybe an information label from the factory build coming unstuck and touching the fan blades.

( Or a mechanics sweet paper. Lol. )

[vitesse]

Changed the pollen filter last week, looking for a grommet to pass a cabin heater cable through. None found but unbolted the filter housing, only two 8mm bolts and noted a large closed flap. Never tried to see if the flap was spring tensioned (like an SD1). Or it might be possible to activate the flap with the ATC (fan speed minimal and see something, or speed up to the 3rd bar and look, just an idea.

Actually when I next change a pollen filter I think I’ll do it the same way, unbolt the housing, remove to the top of the engine, fit filter and refit. Seems easier than fitting in situ.

Regards

[SD1too]

Originally Posted by vitesse

... unbolted the filter housing ... and noted a large closed flap ... Or it might be possible to activate the flap with the ATC ...

It is Mike. Stick your head in the LH footwell, press the recirculation button and you'll see the actuator moving the flap.

Simon

[Devilish]

Originally Posted by vitesse

Changed the pollen filter last week, looking for a grommet to pass a cabin heater cable through.

If you look just under the wiper motor near where the bonnet release cable passes through the bulkhead, there is a blank grommet, always the route I take, unless you already done it.