On 5 Apr 2005 at 8:47, Dave1massey@cs.com wrote:
> As such, as Andy said, as long as it doesn't leak, it has no effect on
> the hydraulic system. It is just a sensor.
True enough, but it can also introduce one slightly sneaky, very
different problem on some cars. (Let me see if I can remember this
without looking at a wiring diagram.)
On some cars with no oil pressure guage, the wiring of the PDWDAPDWA
light was entangled with the Low Oil Pressure Warning (LOPW?)
indicator light. If a DPO had a problem with the PDWADAWA being
tripped and was too unskilled or lazy to fix it properly, he/she (or
you, though you are neither D nor P) might have been tempted to
simply remove the bulb from the PWDWAPDA circuit. The unfortunate
side effect is that the LOPW bulb will no longer glow either, but you
may not notice the effect. Few drivers turn on the ignition and then
study the guages and lights before engaging the starter. In other
words, you would be running with no oil pressure indicator, and
probably unaware of that fact. After all, ignorance is bliss. If
because of time or tool constraints you must take the lazy approach,
unplug the wire to the DAPWDA itself rather than remove the bulb.
One must wonder why They wired it that way. Was it cost or did They
perhaps figure that in the event of a loss of oil pressure a driver
might notice the big red light faster than the little green one
hidden by the steering column?
One must also wonder why They invented such a ponderous abbreviation
as PDWA, or PWDA, or DPWA, or whatever. (You are in a maze of
twisty, little passages, all different.)
--
Jim Muller
jimmuller@rcn.com
'80 Spitfire, '70 GT6+
|