Fannying around

Today’s drive to work was humid. Too humid for a car with climate control.

As the screen got foggier, I had to resort to old-fashioned window opening, in pouring rain, on the M5. This didn’t seem good. The aircon was on, but no lovely cold dehumidified air poured forth.

The blower fan wasn’t running, despite the controls saying it should be.

These days, nothing as low-tech as check the fuse. On goes VCDS, and sure enough:


Address 08: Auto HVAC Labels: 1K0-907-044.lbl
Part No: 1P0 907 044
Component: ClimatronicPQ35 001 0302
Shop #: WSC 00000 000 00000
VCID: E9D34898C025335016B

1 Fault Found:
01273 - Fresh Air Blower (V2)
014 - Defective

A bit of googling and an email to the friendly people at Midland VW confirms this is a common failure for Leon, Golf, A3, Altea etc and the replacement unit is an eye-watering (cue laughter from Andy) £240 or so (non-climate control ones have less electronics and weigh in at just over a ton).

OK then: out with the screwdrivers and multimeter. Getting it out is easy when you know how. This cover in the passenger footwell unscrews (3 torx T20 and 2 handscrews).

The cover in the passenger footwell.



Then a tab on the motor (with an arrow on, and hard to photograph) lifts a little, and the motor rotates and drops out.

The motor is, I’m sad to say, not one of VAGs (or rather Bosch or Valeo’s) better components. The fault was simple: the motor sits on the dirty side of the cabin filter, by the looks of it, and hence gets filthy and the (crap, unprotected, like a cheap PC fan) sleeve bearings seize. The electronics sense this and fail the component (which is good, as it stops it frying the cotroller). A prod with a meter confirmed 12V at the fan, the other connections being either direct speed control or CANbus (I’m not dumb enough to blindly trust the diagnostics…)

The cruddy motor after a spray

A spray with a well-known lubricant, and it’s freed up and working again, at least for a while.

[edit]

Not for long, so a new fan got ordered. This means I have the opportunity to show how the fan comes out, and a bit od dissasembly, which provides an insight into the complexities of the modern car parts supply chain.

First of all, removal. Remove the panel (above), uplug the motor cable and unhook it from the retainer on the motor. Just visible in the RH top corner of this photo is the tab, and arrows showing what to to. Rotate the tab that way, and the motor drops out.

The fan motor in situ. Grab the tab with the arrow, and move it in the direction of the other arrow (top right).

Fitting the new one is easy, line it up, push into place, and rotate in the opposite direction. Refit the cable and the panel below. If you have VCDS, clear the fault code in the Auto HVAC controller.

Investigation

Just for the lulz, I thought I’d take the old fan motor apart.

The motor itself unplugs from the control unit, and a rubber grommet pulls out. You can then lever the motor out, together with a plastic sleeve and three rubber wedges. As you can see, it’s manky, but it’s worth noting it span about as freely as the new one, which means my previous diagnosis of seized bearings may be wrong. Perhaps a brush was stuck: the commutator looked well scored.

Motor and sleeve removed.

The plastic sleve can be removed by looking down through the fan and releasing the latch that holds it:

The latch that holds the sleeve. (to the right and above centre)

Fetching that off reveals the motor itself, but beyond that it’s not really possible to dissasemble further.

What’s interesting is that the motor is a Bosch part:

Bob Bosch’s finest…..

But the complete assembly is a Valeo part (and came in a Valeo box): I am led to belive Valeo are OEM:

…assembled into a Valeo part.

But the control electronics are also Bosch, but can be supplied by Denso, Valeo, or Bosch, according to the OE label on the old unit.

I’d guess the control electronics are still OK on the old one, so I’ll hang on to them. They can be purchased seperately, it seems. The other question is if the non-climate fan motor (£100ish) can be swapped into a housinng for a climate-equipped car (complete price for the climate fan is £215-300, depending where you go).

2 Responses to “Fannying around”

  1. Keith Povall (@soxer99) Says:

    Aren’t you the clever one ? Extra bit of curry for you I think

  2. Willenhall Lad Says:

    Lol! I wondered what was the matter with the Focus’ air-con on Saturday night but I found that turning the heat up stopped the problem. The Skoda’s air-con probably had stopped working years ago but who cares now!


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