If your blower does NOT blow in the HIGH position and, as you say, you
blower motor is OK, chances are excellent that the relay is the sourc
of your problem. This assumes that you checked the FUSE and that's O
too.
When the resistor block fails, it doesn't usually entirely fail... onl
one or all of the slower speeds fail. Still, you should locate an
inspect the resistor block because after 15 years, it COULD hav
entirely failed.
Since the AC/Heater Blower circuit is a high-power circuit, a rela
(not a switch) is used to handle the juice. Sometimes, this rela
becomes so pitted and burned with normal use (normal after 15 years
for sure), it simply will not close with good contact to provide powe
to the motor.
Sometimes the relay will remain closed after the vehicle is turned off
leaving the blower running after the relay literally welds itself in th
closed position.
In both cases, a new $13 relay will fix the problem. If your resisto
block is rusty or just looks bad, you might replace it anyway...
replacement resistor block only costs around $15. Save yourself
future headache
--
HeadlessHorseman
Larry Violette - 21 Jan 2006 05:09 GMT
> If your blower does NOT blow in the HIGH position and, as you say,
> your blower motor is OK, chances are excellent that the relay is the
[quoted text clipped - 15 lines]
> off, leaving the blower running after the relay literally welds itself
> in the closed position.
> I've had 2 or 3 with bad resistor blocks that had to be replaced
> because of blower was not functioning.
Resistor block is usually on plenum on passenger side of firewall.
Just unplug remove block and replace.
About a 3 minute job.
larry