electrical problems

[jtparr]

hi, just bought my first porsche, a 1982 black targa, fantastic fun and used every day

2 tiny problems that I have, firstly the interior light under the targa bar does not work, (fuses seem ok) and secondly the thermostatic heater control between the seats seems to have only "very hot" as a heat selector whether I choose any of the dial up choices
previous owner only did 10K in 5 years and only in dry weather so never really used lights or heater

any help would be much appreciated
thanks

 

[bones]

Hi welcome JT , good choice of wheels. is the light working in any position if not then most likely solution is to change the lihjt unit. If you can use a meter hook that up and look for a current.
To be honest in all my years of owning a 911 the heating has never been it's best point . If you have full heat and no heat on the between the seat control box I would forget that control and learn to use the vents and centre dash unit to regulate the temp'. If you really want to get busy with checking out the heating make sure your heat exchangers are in good condition and that the hoses to and from them are properly fixed and in good repair. Make sure that the hard to get to heater control flaps are opening and shutting properly as the control box dial is turned. You also have an interiot temp' sensor situated near to the rear view mirror and apparently and outside temperature sensor but nobody seems to know where it is. You might want to check if the engine mounted aux' heating motor/fan is working although it's no great loss if it isn't. Good Luck

 

[jtparr]

bones

thanks for the advice, only managed to find time to look at the car whilst cleaning this weekend, (also interesting to read up on the other prolems with other heaters)

The previous owner has had the rear view mirror moved to be stuck onto the glass and consequently there isn't a ribbed rubber heater sensor thing at all near the mounting point for the mirror, just a hole !, do you know if these things are easily available (next problem will be to wire it up as can't see any wires in the hole !) The car has stainless exhaust and heat exchangers and the pipes I can see from a quick look underneath look new and well connected, but I have not had time to inspect control flaps (where are they by the way !)

My other problem of the light fixture is no clearer, the casing looks fine, and all the fuses under the front bonet are fine, but then I noticed that the interior light in this area does not work and there are 3 wires that are severed

Being a novice to car maintenance I think I might be better to find an auto electrician, I live close to Woking/West Byfleet, do you know of any in this area

thanks
Jonathan

 

[Guest]

but I have not had time to inspect control flaps (where are they by the way !)

They are in the firewall, near the top, and there is one each side. They consist of circular 'valves', which open/close by rotating, and work by diverting the hot air into the car, or back into the engine compartment.

So, if you lie under the engine, and look forward and up, then ......

In my experience, they are a b**gg*r to get at !

 

[bones]

It's normal for the mirror to be stuck to the glass on an SC. If you have no knowledge of wiring prob's I suggest you find a an auto electrician who is a recommended specialist in Porsche systems, any old auto electrician won't do.
The interior sensor located behind the rear view mirror is available directly from any Porsche GB parts dept. I'll check on my wiring diagrams to see if the bonnet light is on the same circuit as the int' light , it would make sense if it was.

 

[bones]

Pull the interior light out, (carefully prize out with a small flat blade electrical screwdriver) and check the condition of the internals , even replace the bulb , they are pence. The interior light is on the same circuit but I can only see two wires going to the luggage light.

 

[jtparr]

bones

success, well at least some !

thanks for the advice about the fixing of the rear view mirror, after an hour or so in the cold this afternoon some success, managed to retreive a single white coloured wire with a simple small circular looking plug (like a mobile phone charger type connector) from the hole where the old sensor was, hopefully this will help

also managed to connect all of the wires in the front luggage space, so now have a working interior light, but it only works when switched on, as opposed to activating when the door opens, still better than none at all !

front luggage area was a bit of a mystery as I could not locate a corresponding brown wire to conect to the one that leads from the light unit. Looking in the Haynes manual (page 299 in my copy) the brown wire is said to lead to a "rear lid switch", which has taken me a few hours before I realised that the bonnet is the switch, and I am missing the tiny type of switch such as you have on the doors to activate the interior lights, hopefully these are also available, will ring around tommorrow

not bad for a novice

jonathan

 

[bones]

Good stuff the interior light should be off in the middle position (flat) on all the time when depressed at the front and on only with the doors open when pressed in the rear position. The door switches are prone to failure, before removing grasp the black central plunger and hold steady whilst you undo the retaining nut with a ring spanner. If you don't do this you stand a good chance of twisting off the single brown wire and losing it in the A pillar.

 

[jtparr]

bones
apologies for the delay in replying, spending the last few weeks extending the garage for the porsche has meant not much work on the car itself, but at least I managed to purchase a new temperature sensor from Jasmine which thankfully sorted out the monster heat production, so now I can drive without melting my legs

thanks again for the advice, will sort out the other issues in my roomy garage as time permits.........

jonathan