RE: E30 cruise control cut-out SOLVED!

["Fadeev, Alex" <Alex.Fadeev@xxxxxxxxxxxxxx>]

> Alexander Fadeev writes:
> 
> > My cruise control is starting to act up. Everything points towards
> > an intermittent electrical connection (going over bumps resets 
> > the cruise, after a few additional bumps it will come back, etc).

	BIG Thank You to: 
Brett Anderson 
Jim Cash
Jason Lile
	I had just solved the problem over the weekend.

	The answers to my questions were:
1). The cruise control brain on E30's is above the DME in the glove box.
Follow the right hand side glove box strap. It's a small silver box with a
blue connector just like the one for the back of the instrument cluster.

2). The culprit in my case was a heavily oxidized cruise control (CC)
connector at the instrument cluster. The actual green two pin female
connector to the cluster was all snug and well. But in its infinite wisdom
BMW placed a big green intermediate connector between the CC feed and the
cluster (only the CC connector plugs into that thing, although there are 6
or 8 extra male ports). 
	That intermediate green connector has four deep 1/2" pins plugging
into the cluster that were very heavily oxidized. Cleaning them with a
little file and slightly bending them to keep the connector snug inside the
instrument cluster did the trick.

3). Things to check if you have intermittent CC problems (mostly quotes from
Jim Cash and Brett Anderson):
	- check the fuses; check full 12V _to_ the fuses
	- check 12V to the cruise control stalk
	- tighten the ground at the stalk - Phillips screw behind the
steering
	  wheel with a brown wire leading to it. If you have an airbag you
may
	  not be able to remove the steering wheel without professional
help.
	- check the switches behind the brake and clutch pedals. A bad
switch 
	  or a loose pedal hitting the switch will reset cruise control.
	- make sure that the connections are good between:
		- cruise control stalk & the harness clipped to the steering

	 	  wheel column
		- the harness & the back of the instrument cluster 
		  (little green connector -> big green connector ->
instrument cluster)
		- harness & the cruise control brain (blue plug)
	- double check if the speedometer is working. No reliable
speedometer 
	  reading = no mph input into cruise control brain => no cruise
control. 
	  The usual suspect is the rear differential sensor
	- And finally inside the cruise actuator (the control unit under the
	  hood) there is a rheostat that provides feedback to the unit under
the
	  dash. If there is any dirt on the moving rheostat connection, you
	  guessed it - the cruise cuts out.  If you open this unit be
careful -
	  springs have been known to pop out  -and make not of the way the
cable
	  is wound on the wheel before taking it apart (unless you like
puzzles).

	If all of the above fail to help, follow Bentley to check DME
outputs. If that doesn't help, either start swapping parts or see a
mechanic.

have fun,
alex

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