Radiator Fan relay sticking - '86 4kq

[Dave Conner]

Ti,
I went out and looked again at the relay panel, etc. and confirmed there is
no evidence at all of any corrosion or overheating, etc.  And you are
correct there is no fuse for this fan... at least not AFAIK.  The used
relay(s) I've swapped >look< new and came from sockets where they would
have lived an easy life... the horn circuit for example.  This is the
common Bosch 40 amp relay.  Maybe I should buy a new one and try it to try
and rule out this possibility.

I hate to replace things like the fan without direct evidence of
malfunction.  But my teenage daughter is the primary driver of this car now
and we can't afford for her to be getting stranded.  
Dave C.  


>Dave Conner writes:
>> I read suggestions in the archives that the old/original fan may have
>> increased electrical resistance to the point where it draws higher current
>> that welds the relay contacts together.  
>> Is there a way to test the electrical resistance of the fan?
>> Should I just assume this is the case and replace the fan? 

>At 10:22 AM 12/27/2000 -0800, Ti Kan wrote:
>Does the relay socket and the relay itself show any signs of overheating?
>Also what about the condition of the contacts in the relay socket?
>
>It's also possible that the relay fan itself is on its way out, increasing
>current draw.  I don't have a '87 4kq wiring diagram handy to look at,
>but some Audis' radiator fans are not fused, and if the fan seizes one
>day you could have a burnt wiring harness at the least, or even a fire.
>
>-Ti