355 timing actuator (air direction motor) removal

[HardtopManual]

I've been attending to a broken HVAC system on my 355 and it seems that everything that could have gone wrong, has gone wrong - faulty control unit (now repaired), faulty water valve (now replaced, hoping to find a replacement for the knackered DC motor in the old one so I can have a spare) and faulty redcirc flap motor (3D printed a new gear in polycarbonate). The "timing actuator" (blower direction motor) is also not working, but I can't for the life of me get access to the screws holding it to the HVAC unit. I've contorted myself in the footwell, removed the central air vents and the instrument binnacle, but cannot get to those screws. It looks like I might have to remove the entire HVAC unit, which I really don't want to do.

Has anyone here done it (on a RHD), and if so, how?!

[HardtopManual]

Ha, I just set it to manual mode and did a battery reset, lo and behold, some whirring emanated from behind the dash and my air direction motor has now joined the party, thanks Drew! My HVAC system now appears to be working properly, for the first time in years.

[HardtopManual]

btw if anyone needs a repair on their HVAC control unit (p/n 64324800 for future Googlers), I can recommend https://crashdata.co.uk - they charged £200 to supply and replace all the op-amp chips plus a few other components and had the board back to me in a matter of days.

[HardtopManual]

Cactussed said:

Excellent result, and also thanks for the heads up on the fixing guys.
Presumably any other ECU / boards would also be within scope

Assuming components are still available, I don't see why not.

[HardtopManual]

355spider said:

My heater only works on manual also, Im not entirely sure why but a previous owner has wired up a fused tripped circuit breaker in the luggage compartment instead of the 30amp fuse popping, I’m not sure why, although it’s not trippped for a few years now so haven’t bothered looking.

Will that place be able to repair the cat ECU’s? I’m
Getting error codes for all 3 and apparently there prone to going wrong again, not bad for £1200!

Cat ECUs probably not worth the faff, being very heavily potted. The cheap solution is to take the bulb out of the dash, the more expensive one is to replace with improved aftermarket units, see https://technistrada.com/catalytic-temperature-con...

[HardtopManual]

Turn off the battery isolator under the access panel in the front boot. Leave a few seconds. Switch back on.

I doubt that will get your heater valve working though, so you'll need to remove the carpet in the front boot and have a look at the valve. Either:

1) The valve itself is seized but the motor still works. This can be replaced with a lightly modified VW part 171-819-809/E

2) The motor is knackered. Depending on the failure mode, this may be repairable. The brushes had perished on mine. I replaced just the DC motor with one taken from a generic Bosch part fitted to various Saabs and Alfas - Bosch 390 721 005 or similar. It all comes apart with a screwdriver.

3) The HVAC ECU is knackered. This can be repaired by a company called Crash Data in the UK - https://crashdata.co.uk - IIRC I paid £200 for them to replace all the op amps and some other failed components. I then fitted heatsinks to them to try to avoid them burning out in future.

[HardtopManual]

I should add - if your motor is irreparably damaged, you can replace the whole thing with a standard 5-wire heater valve. I did this temporarily while I had the original part on the bench. Vintage Air part 461170 but you'll have to fab a bracket and sort out the wiring. As far as I can see, this is what Ferrari supply when you order supercession 63306400A from them.