Hi i am new to saturns me and my wife just bought a 1996 Saturn s series sedan and we found that if you turn the heater on the speedometer stops working but once you turn it off it starts working again. So i was wondering if anyone has had a similar problem and if so whats wrong with it and how'd you fix it? Thanks.

 

wow -- never seen that before... this should be interesting.....
Anything else acting funny/not working on the dash/instrument cluster?
Is it only the heat? Does it behave equally weirdly when you turn on the A/C?
Any other performance problems?

 

And nope everything still works when that stops and it still works when the AC is on too only when the heater is on is when it messes up.

 

alright i have been able to make up some more info that may help solve the problem. We have figured out that the speedometer does not work when it is cold out till the car is warmed up we thought it had something to do with the heater at first cause it was cold so we would turn it on so we thought it had something to do with that till today when we started it up and it didn't work and the heater wasn't on. any ideas why the cold is interfering with it?

 

needle sticking....

 

gonna check that today when i get a chance.

 

Load test Alternator
Load test Battery
Check both battery cables.
The positive cable could be corroded inside the wrap at the battery end

Low voltage or amps can cause all sorts of problems

If you see any sign of a past battery leak pull the battery, pull the battery tray and start cleaning and checking the wires under the battery tray.