Hot dashboard on a cold day

Hi everyone,
I own a 2005 volvo s40 i5. Recently I noticed that my dashboard gets extremely hot after just couple minutes of driving. Originally I thought this has something to do with the car’s black interior. However, my suspicion changed when I noticed that the dashboard became very hot even on cold rainy days. (Below 60 degrees) This presented couple issues while driving. 1) On cold days, my windshield would fog up very easily. 2) on hot days, the cabin of the car can be intolerably hot. Both of my check engine light and my airbag warning lights are on. However, auto mechanics cannot diagnose the problem because they can’t get a reading through the diagnostic scanner. They said most likely the car has a electrical short somewhere.

What do you think the problem is? Could it be an electrical short that cause excessive heat in the dash? Maybe the engine heat is venting into the dashboard? Fix?

There will have to be a lot of guessing here, especially since you have already taken the car to a mechanic and he has turned you away.

You have several separate problems. The hot dashboard and the fogged windshield clearly indicate a problem with the doors on your heating system that control airflow, or possibly a hole in the airbox in which heat transfer takes place. Or both. You will have to disassemble the dash to learn the exact nature of the problem.

The lit warning lights indicate a (probably) unrelated set of problems. If you cannot even get a diagnostic reading these will be difficult to track down. You will need to see a Volvo specialist, and it wouldn’t surprise me if they were stumped too. Good luck.

I don’t know anything about Volvo’s, but the heater core is behind the dash on many cars. If the heater core was leaking this could cause the windshield to fog easily, would contribute to heat entering the cabin and if the heater core is located near the ECU or air bag diagnostic monitor it could have leaked on them causing the problems with not being able to pull the codes and the air bag light.