Heater Problem

[PaulV]

I've got an 89 Beretta with 291,000 miles.  Last month the heat went out, (i.e. no fan and no heat).  I took fuse #8 out checked it (not blown) and put it back in.  The heat worked fine then.

Today I had the same problem appear but re-seating the fuse did not fix it.  Any suggestions?

(I noticed that my digital dash is on this fuse also even though the owner's manual doesn't mention it.  Is this correct?)

[Jeff P]

Yeah, the fusebox cover and owner's manual don't mention lots of stuff.  The digital dash gets power from fuse 8 when the ignition is in Run, and also uses fuse 8 for daytime illumination.  As far as the blower problems, remove the fuse, turn your ignition to Run, and use a test light or a meter to check for power at Fuse 8.  If there's power, leave the ignition on, reinstall the fuse, turn the blower to low, and disconnect the purple wire from the blower motor.  Then check for power at that wire.  If there's no power, check for power at the brown wire coming from the A/C blower relay, which is on the back of the relay bracket on the firewall and should be the one closest to the blower motor (wires are orange, red, brown, and purple).  Post what you find here

[PaulV]

There was power all the way to the blower motor.  I cleaned the connection to the motor and now it works!  Flow seems a bit low though, maybe it's just the age of the motor.

[Jeff P]

Good, I'm glad you got it fixed In addition to an old blower motor, the low airflow may be caused by a restricted evaporator core (looks like a mini radiator).  It's in the big black HVAC box inside the dash and you have to remove the heater core to get to it.  You can also get to it from the engine bay by removing the blower motor housing.  Over time the evaporator core gets clogged with leaves, pine needles, dirt, hair, you name it.  It's definitely worth a cleaning if you're not happy with your airflow.