Heating system

[sib8292]

On Sunday I decided the time had come to start to fix a non essential item that I have done without during my 12 years of ownership; get the heating working properly.

Having removed the engine blower motor without much trouble, I tested it by applying 12v power and found it wasn't working. Strip down showed that someone had tried to repair before and the fan ran out of true. So have decided to buy a new one (any ideas where; they all seem to be about £140).

While I was about it I decided to check if that was all that was wrong. The engine compartment relay works OK; I swopped it for the horn one to check. The fuses in the engine compartment seem OK.

What I can't find is any power getting to the wriing connector to supply the motor. I assume that it is activated by the ignition being switched on; or does it require the starter to be actually operated/engine running?

I think that the console housing the auto control and emergency override lever also contains wiring from the ignition switch, and therefore one or other has to be activated to switch on the blower motor? Is it accessible without taking out one or other of the front seats? The auto control doesn't do anything so maybe there is a power problem there rather than in the engine compartment.

Anyway any ideas gratefuly received!

 

[SJW BASIRE]

Turning the auto control should make the fan start blowing if it is still working and no one has pulled the red lever.I junked my autoheat system and fitted the earlier style twin lever set up.This system is simple, reliable and makes you feel like a Lancaster bomber pilot!The fan starts blowing when I pull up the levers because of a microswitch on them-this is maybe what is faulty on your car as I would expect the principles involved are the same.

 

[sib8292]

Thanks Steve; I'm trying to keep it standard so want to get the auto system working if its not too expensive. I'm going to investigate the box next and as you say the micro switch may be the problem. I'm afraid the red lever has been used by me over the last 10 + years cos I couldn't get the auto control to work..

 

[Guest]

The control box between the seats comes out easily without removing the seats - just 4 bolts to remove, using the thinest of fingers. Removing the connections, and then replacing them, may be all that is needed, as they do corrode.

Lots of odd bits to go wrong, including the thermostats, so a logical check of all the connections etc. should get you there.

 

[sib8292]

Well I have made some progress. First thanks to Jeremy Holmes for reading my first post and selling me a perfectly serviceable engine compartment ("warm air") blower.

BUT I still need to get the power to it. I took out the front sets; easy peasy, and gives me good acccess to the auto control box betwen the seats. Couldn;t see anything obvious but when I reconnected the main 3 pin connector and switched on; hey presto the motor worked and has now ended up at fully on position. After that, nothing.

I've also now got the dial illumination working so have obviously restored a bad connection somehow at least to some extent.

So maybe I need to check the sensors, or maybe I should now put it all back together and see if I have power to the engine compartment blower.

Menatime I'd really appreciate some kind soul looking at the underside of their light switch. I've got a blue/gray wire from the switch with a manufacturers connector on it, not connected to anything. I've also got a yellow wire coming form the loom with a manufacturers conector on it; I could plug them together but I really don't want to do so without knowing what they do. So if your car has these two wires connected together please tell me; and iof not anyonme want to hazard a guess as to what they are for?

 

[Bazgillie]

Sib
There was a good article in 911 and Porsche world magazine a couple of months ago which covered the heating system in good detail. Sometimes worth a look on E-bay but check the proper price first.
Baz