RE: 4000 power locks

[HAREST@allenbrook.iix.com]

I don't have my manual in front of me, so I can't give specifics as to
wiring pin-outs etc.  Most common failures of the central locking system in
the 4k chassis is with the wiring in the driver's door loom.   The power
mirrors, power locks, and LF window wiring all pass through to the driver's
door, and typically break and short out over time.  The Book of Robert may
give a diagnostic procedure, but again, it isn't in front of me.  So here's
one off the top of my head that should be close...

For those who still need a 4k/q Bentley, there is a place advertising in
Euro-car this month that has 4k/q manuals for $77. No affiliation, yada yada
yada. Heck, I would have to go back and look through Euro-car just to
remember their name.  Might be Rapid Parts in NY though...

1) When you activate the switch, do you hear the pump (in the RR of the
trunk, near gas filler pipe, in an insulated/padding box) run?
    If yes, start searching for a vacuum leak in the system.
    If no, keep diagnosing;
2) Do you have power to the switch in the driver's door actuator?
    If no, check for a bad fuse, or bad wiring in the door loom as it passes
from the A-pillar, through the rubber bellows, and into the door.
    If yes, keep diagnosing;
3) Does the pump get power when the switch is actuated?
    If no, check for a wiring break in the driver's door loom. See above.
    If yes, keep diagnosing;
4) Does the pump run when power is applied? Either from the stock wiring, or
by testing it?
    If no, replace pump.
    If yes, keep diagnosing;
5) Does the pump generate vacuum or pressure (does it suck or blow) when
activated?
    If no to either, replace pump.
    If yes to both, go back to step one (ask the Q-list and/or recheck all
components), check for a vacuum leak.

HTH,
-Stott

> -----Original Message-----
> From:	Mark L. Chang [SMTP:mchang@ece.nwu.edu]
> Sent:	Tuesday, May 05, 1998 11:13 AM
> To:	Derick Farfan
> Cc:	quattro list
> Subject:	Re: 4000 power locks
> 
> I believe it is only the driver's side door lock that actuates the whole
> system.
> 
> Be glad, at least yours work!  :)
> 
> PS> Anyone want to tell me where to start to diagnose mine?
> 
> mark
> 87 4kcsq -- no power lockage.
> 
> On Tue, 5 May 1998, Derick Farfan wrote:
> 
> > I was wondering if the power locks in my 85' 4000s (non-quattro) is
> > supposed to work with the passenger's side door lock as well as the
> > drivers, or is it only the drivers.
> > 
> 
>                     [PGP] finger mchang@ece.nwu.edu