Interior heating sensor

[nervy]

Hi. The interior heating sensor in my SC Targa is misbehaving. In hot weather in the summertime, it turns on full heat and when it's cold or I need to clear some condensation, it doesn't open. I have taken it out and cleaned the connection, and it has worked perfectly for a while, but then goes back to its old tricks.
So I phoned Lancasters in Colchester and asked about getting a new one.
Porsche no longer have them listed and there were none at any other dealers.
Does anyone have any ideas as to what can be done to remedy this problem?

Cheers.

 

[bones]

The operation of this system in a Targa is never brilliant but it should work something like this. On a cold day if you turn the dial to the even the first position it will probably open the heater flaps fully, on a hot day hardly at all, however once on the move due to the fact that the Targa is not wind tight it will fluctuate constantly. There are two sensors one in the car and one outside by the heater flaps.

 

[nervy]

Thanks Bones.

The sensor is definitely at fault, because just touching the casing makes the lever yo-yo up and down.

Is there an alternative to the sensor as they are no longer available from Porsche.

Cheers

 

[bones]

You can remove the auto-heating control and backdate to a manual system with two levers one for each heater flapper valve. However you have to also fit a the backdated handbrake fixing too.

 

[Gary.H]

Hi Nervy,

The heating sensor in my '82 SC coupe is actually missing and I had no luck in locating one either :-(

Not sure if the operation is different in a targa, but the following worked for me.

I had the sensor wiring disconnected and the lever altered to manual ( I think there's a link you need to remove ) at the central console heater control and I now just use the heater lever manually to control the hot air.

The only thing to remember is that you need to turn the rotary heat setting control ( in your centre console ), which now won't be controlling the thermostat (!) to (IIRC) about 3 to activate the engine blower. You can feel the strength of the hot air increase once the engine blower is on.

I intend to switch back to thermostat control once I locate an internal thermostat sensor, so if you find a source let me know

Cheers - Gary

 

[bones]

According to my parts pdf. the interior sensor is part no. E911 659 105 01 but check with the Porsche parts department before ordering to see if it is right for your year, I bet they are all the same.