Heater controls/bowden cables

[The Milkman 10]

After some help please

 

Finally got the bowden cables off of the heater control and managed to get the control unit out. Of the three cables, two seem to move okay and one is really hard to move so I assume I need to replace it, where's the best place to get a new cable please?

 

Two of the cables work off one toothed wheel on the back of the heater control, it's the lower one of the two, attatches to the arm that is under the toothed wheel. Where does the other end of the cable disappear to?

 

On the rear of the control unit again, the thin metal strip (that sits between two of the wheels and gives you your clicks)had been forced under one of the wheels. I've managed to get it out but the strip won't stay in place now and the toothed wheel with the two arms does not touch the toothed wheel behind the control knob, so the knob spins and does nothing!

 

Considering the price of second hand ones on eBay, am I better off biting the bullet and buying a new control unit? If so, there are two part numbers on the underside:-

 

358 819 045

 

and

 

358 820 045

 

Which would I use to order the correct replacement?

[The Milkman 10]

Right, just managed to get Photobucket working

 

 

You can see that the two toothed wheels on the right aren't touching and both the arms are flapping about. The bottom toothed pulley doesn't feel like it's sitting where it should and it all generally feels a bit 'wafty'

[bmwcompact 10]

I see you have now bought a second hand set on this forum. Be careful when you reattach your Bowden cables as its easy to break the plastic chassis: the clips require force to fit. You may also want to remove the thin metal V shaped spring altogether. Its purpose is to give a positive location to the position of the control knob, without it the knob just turns smoothly thru its whole range. These springs often come loose, slide under the wheel and jam everything: the user forces the knob breaking the wheel. If you dismantle your broken unit you will probably find the wavy tracks on the underside of the wheel are broken and since you say the lower wheel no longer meshes with the vert upper wheel, youll find the boss (rotation point for the wheel)has broken off the chassis.

[The Milkman 10]

I see you have now bought a second hand set on this forum. Be careful when you reattach your Bowden cables as its easy to break the plastic chassis: the clips require force to fit. You may also want to remove the thin metal V shaped spring altogether. Its purpose is to give a positive location to the position of the control knob, without it the knob just turns smoothly thru its whole range. These springs often come loose, slide under the wheel and jam everything: the user forces the knob breaking the wheel. If you dismantle your broken unit you will probably find the wavy tracks on the underside of the wheel are broken and since you say the lower wheel no longer meshes with the vert upper wheel, youll find the boss (rotation point for the wheel)has broken off the chassis.

 

Cool, cheers mate.

 

Do you know where the other end of the cable atatches too?

[bmwcompact 10]

It was last year that I had my control unit apart. From memory 2 of the cables operate flaps on the passenger side and the third is on the drivers side low down close to the transmission tunnel. I dont remember the respective/function of these: one is the main flap which accesses heat from the matrix, one directs this between face and footwell and one is just for the demist (I think thats the one from the lever underneath the broken wheel). I didnt replace my cables so am not sure how difficult it is to replace them. I did remove shelves/trim under the dash to see where the cables went and verify they functioned. There are many threads on replacing the heater matrix/heater controls if you can find them. I am also aware that sometimes the foam surround on the flaps comes adrift and makes the operation of the flaps difficult. So the problem may not be your cable. I am not sure that the Bowden cables are still available. I find the google search better than the forum search in finding corrado problems/solutions: google takes you to the appropriate forum threads!

Edited August 3, 2013 by bmwcompact

[The Milkman 10]

Cheers again. I'll get all the bits together and then pull the underneath of the dash off and have a go.

 

I can find loads of info about the control unit and matrix but not a lot on the cables, I'll keep hunting

[tony_ack 0]

It's a while since I've looked at the standard setup, but IIRC one cable operates the flap inside the ducting in front of the matrix (temp control), one operates the big flap at the front (to the dash vent ducting), and one operates the flap up to the windscreen ducting.

 

I remember that one of the cables is a complete sod to change at the ducting end

[The Milkman 10]

Cheers mate.

 

Too out the under dash covers, started on the drivers side as that is the way the cables lead from behind the heater control

 

 

Only to find they go round the back to the passenger side

 

 

Edited August 13, 2013 by The Milkman

[The Milkman 10]

Two of the cables move nicely and you get a good 'thunk' noise at each end of their travel, but one is a bit 'stickier'. It moves but needs a lot more effort. It doesn't appear to be the cable but I'm not sure where else to start looking.

 

This one

 

 

 

Any ideas please?

[davidwort 0]

check the blue cable, the one that goes in between the distribution unit and does the dash/windscreen to feet flap, it takes quite a bend and the slightest wear or kink in the cable can make it quite stiff. try operating it with the cable straight. The flap sometimes jams, I had one actually break the lever off the flap (well a former owner did) which meant changing the whole distribution unit as it's moulded in place IIRC

 

edit: no, sorry, not the blue one, but the black one next to it that DOESN'T terminate underneath the distribution unit but up behind it

[lard44 0]

Do you have the part nos for the Bowden cables? Just replaced my heater controls only to find that the control unit was sound...but the upper black cable is kinked...

[davidwort 0]

bowdens:[ATTACH=CONFIG]75295[/ATTACH]

[tony_ack 0]

I had one actually break the lever off the flap (well a former owner did) which meant changing the whole distribution unit as it's moulded in place IIRC

 

Don't be too harsh on the former owner - it's incredibly easy to do as it's not particularly strong and you need a fair bit of force to get the old cable off.

 

On the plus side, when I did the same it was a good excuse to put in the climatronic and do away with the cables and brittle dials!

[Sean_Jaymo 0]

Exactly why I fitted my climate too!

 

Oh and whinge moment here: Call me pedantic if you will, but these cables are technically teleflex cables. Despite what wikipedia says, bowden cables are pull only and rely on a spring (normally) to return the cable to it's original position - like on a push bike or throttle cable. Teleflex cables are push/pull and have rigid steel cables instead of flexible cables. I fix aircraft for a living and things being called the wrong thing get on my wick! Bit like their, there and they're mistakes to me!

 

End of rant! Return to normal service!

Edited August 13, 2013 by Sean_Jaymo

[The Milkman 10]

check the blue cable, the one that goes in between the distribution unit and does the dash/windscreen to feet flap, it takes quite a bend and the slightest wear or kink in the cable can make it quite stiff. try operating it with the cable straight. The flap sometimes jams, I had one actually break the lever off the flap (well a former owner did) which meant changing the whole distribution unit as it's moulded in place IIRC

 

edit: no, sorry, not the blue one, but the black one next to it that DOESN'T terminate underneath the distribution unit but up behind it

 

It's the black cable going to the arm with teeth on it (in the last picture) that is stiff