Saabscene Saab Forum - Saab Technical Information Resource banner
1 - 7 of 7 Posts

·
Registered
Joined
·
224 Posts
Discussion Starter · #1 ·
Hi all. I wanted to ask if the external temp sensor is only there for the driver's information or does it play a part in the climate control system. I am asking because the temp I am getting is usually 10 degrees © lower than the actual temp. Can I just disconnect it, or the climate control doesn't work without it?

Thanks

Harry
 

·
Registered
Joined
·
102 Posts
My 300zx has a similar climate control and when the external temp sensor broke (went open circuit) the entire AC stopped working.

The computer thought it was always -40degC outside so it never bothered turning the AC compressor on.

I guess you may find the same if you disconnect it.

I also suspect that the engine management uses the same sensor for outside temperature
 

·
Registered
Joined
·
354 Posts
Yes
External sensor is part of the acc system. This is why if you are sitting in traffic the sensor under the front bumper (i.e too near the engine) gets hot and the acc blows colder and colder thinking the weather's getting hotter!

Julian
 

·
Registered
Joined
·
8,948 Posts
The Acc uses:

The exterior air temp sensor
The Dash top sunlight sensor
The interior air temp sensor/fan
An internal air mix temp sensor
and something else (possibly a water temp?)

From this it tries to work out the bast setting for vents etc.

Is your external temp sensor over exposed? and getting wind chill?

Andrew
 

·
Registered
Joined
·
8,948 Posts
Possibly it will think the external temp is

139deg F (the max) and always run in recirc mode (causing massive misting in winter - how do I know that.....)
or

bloody cold def F and do the windsceeen demist thing all the time.

Andrew
 

·
Registered
Joined
·
300 Posts
On ACC 2 there is one ext temp sensor under front bumper that is used by the EDU. The EDU then converts this to a digital signal and sends it to the ACC. It is not however a primary source for the ACC as is for example the int temp sensor.
The rise that occurs sitting in traffic will therefore not have a dramatic effect.
 
1 - 7 of 7 Posts
Top