My heater is not working. Fan is blowing air, but it's cold most of the time. Every once in awhile I'll get warm air for a minute or two. I checked the codes (using the auto/off) buttons and I get a "0". What else could be wrong?
It's an 04 9-5
On the Saab 95 04 the most common issue with the fan blowing cold air all the time is the temp motor behind glove box. Click on the forums link below to add more info or to view additions to this topic.
What I've done so far:
Heat engine up with cabin air blowing. Verify that heater core supply lines are hot at the fire wall. Mine were cold indicating that the hot water isn't making it by the Heater Bypass Valve.
Verify Heater Bypass Valve and the Secondary Air Injection Valve is working (It has electrical connector and 2 vacuum hoses). Bypass the Secondary Air Injection Valve by "replumbing" the vacuum lines. My heat started working. Yipee!!!
The Secondary Air Injection Valve is a solenoid that allows a value to open the Heater Bypass Valve.
I left the vacuum lines bypassed and checked the solenoid. It works....
The solenoid terminals have 35 Ohms resistance either direction. When I connect the terminals to the car battery the soleniod clicks open and the air can move through the valve. It draws 350 milli Amps when active.
Now check the connector. The voltage at the connector to the solenoid is 12 volts when the engine is running. When I connect the solenoid to the connector the voltage drops to zero and it draws 20mA. (That's bad!)
For now I'm leaving the solenoid bypassed and the heating system works fine. My guess is that the AC works better when the bypass is operational.
I can't figure out where the solenoid wires go! Anyone have an idea? I was hoping they'd go to a relay but can't find it.
Thanks in advance...