[Bulk] Re: Passat starting - ignition switch again?

[urq]

IME, critical systems like ignition and starting systems are powered
directly from the battery and ignition switch and not the load reduction
relay.  I don't know about the Passat though.  Have you seen a starting
issue that was clearly shown to be due to a problem with the load reduction
relay?  

VW put out a TSB many years ago to add a load reduction relay of sorts to
resolve customer complaints of starting problems when a low voltage was
found at the starter solenoid.  I almost added on to my urq, but I've found
that if the solenoid won't pull in at 10V a replacement starter will resolve
the issue.  If someone is planning to add headlight relays under the hood
the relay box is a perfect location for a starter load reduction relay.
Much like what is done with the headlights, the start line from the ignition
switch would energize a relay coil and the NO contact on the relay would
connect to the starter solenoid.  

Steve Buchholz

-----Original Message-----

Possibly coulc it be the load reduction relay? As
far as the back-up power, a 9 volt battery hooked
through the lighter usually works.

John
---- Original message ----

  >Hello Everyone,
  >
  >Thanks for the replies!
  >
  >I did some more measurements today. I did catch
  the car once when it was not starting. Keeping the
  key in the start (cranking) position the voltage
  was 11.43V. I measured this at the cigarette
  lighter, so it was not at the starter.
  >For reference, I also did measure two of my other
  cars that have no problem starting. Four cylinder
  cars though. One of them was 10.3V, the other
  10.4V.
  >The Passat has less than 20K Km on it, so it
  should not be a worn starter or corroded wires,
  but anything is possible.
  >To take out the battery and clean the poles on
  this car is tricky, it needs back-up power. It
  would forget the throttle positions. The throttle
  adaptation algorithm can only be initiated by a
  VAG-COM type computer.
  >I will continue to investigate. I will measure
  the specific gravity of the electrolyte in the
  battery. I will also probably instrument bits and
  pieces of the starting circuit, to measure voltage
  directly at the solenoid, and at the starter.
  >
  >Thanks, Peter