[TR] Master Cylinder help part II - PDWA

[Dave1massey at cs.com]

In a message dated 4/29/2009 9:17:13 PM Central Daylight Time, 
jimmuller at rcn.com writes: 
> Are you sure about what it won't tell you?  Or am I misinterpreting 
> what you said?  I don't have a wiring diagram in front of me at the 
> moment but I'm quite certain I think I remember that on the GT6 if I 
> disconnect the PDWA wire neither the brake nor the oil pressure light 
> come on at all.  I know this because when I bought the car a DPO had 
> done that very thing because the PDWA was stuck.  I re-attached the 
> wire and both lights started working, with the brake light on all the 
> time.  So I took the PDWA apart and freed up the piston.  If your 
> wiring is the same then someone must have made it different, if you 
> know what I mean.
> 
We are talking about a '72 TR6 here, right?  I don't know why a GT6 would 
be different but on a TR6 disconnecting the PDWA switch will not prevent 
either the Brake Warning Light nor the Oil Pressure Failure Light from 
illuminating in response to the oil pressure switch.  What it will do is prevent the 
Brake Warning Light from illuminating at full brightness all the time (when 
the key is ON).  This is exactly the failure discussed in the thread.  Dodgy 
connections at the PDWA switch is the same thing as a disconnected PDWA 
switch.  

The Bulb Check function does just that: check the bulbs.  It does little 
more.

Dave