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Re: after-run timed-ness

Luis Marques wrote:
> Yes, the 4kq after run relay (separate from the rad. fan relay) does
> have a timer buit-in.  It works off a parallel RC (resistor-capacitor)
> circuit.  The capacitor is charged off the ignition (terminal 15) and
> discharges through a resistor.  When the capacitor is charged, the
> temperature switch on the valve cover controls the fan.  After the
> capacitor is discharged, the relay quits working regardless of the valve
> cover switch.  This prevents the battery from being drained by the
> radiator fan.  The ignition needs to be turned on to reset the timer.

Hmmm. Mine, and others I've seen, must be broken. Mine's run up to three
times. (perhaps it has something to do with driving "style?" ;-)

'87 4kq
'89 200q