E30 Cruise control

[wnw65]

Howdy enthusiasts,
I converted my E30 325i from Auto to 5 speed manual. Now my cruise control does not function. I do know that cruise control works on manual cars because I owned a 320i decades ago that had it.
So now the question is, why does it not work after the convertion?
Cheers

 

[Big Daddy]

Clutch connection? There is some special wiring that a manual with cc uses.

 

[jrt67ss350]

What did you do with the neutral safety switch wiring? The neutral safety switch in an auto car will kill the cruise control if you shift into neutral. Likewise, manual cars have a switch on the clutch pedal that will kill the cruise control if you press the clutch pedal and close the switch.

 

[Big Daddy]

Thanks Justin, that is what I was getting at.

 

[echothreezero]

WNW65, I would be interested to hear of a solution if you find out elsewhere. I have a newly purchased SA e30 325i with Cruise. It is auto, but not for long as I can't stand auto bimmers, and after a few of these conversions I have it down to a fine art. However, this will be my first with cruise control...

Cheers

 

[jrt67ss350]

This article is making reference to the wiring at the neutral safety switch (this is where your problem is most likely at):

http://www.bmwe30.net/cgi-bin/datacgi/database.cgi?file=articles&report=view&ID=00174&Section=11

 

[wnw65]

What did you do with the neutral safety switch wiring? The neutral safety switch in an auto car will kill the cruise control if you shift into neutral. Likewise, manual cars have a switch on the clutch pedal that will kill the cruise control if you press the clutch pedal and close the switch.

The neutral safety switch wires are shorted together (green wires as I recall).
You are right in saying that the clutch pedal needs a switch do disengage the cruise control.
I had a look at another E30 manual car (factory standard) last night. It has the switch/sensor on the pedal. I am going to source this equipment and give it a bash.
Else if all else fails I am ripping the cruise control eqiupment out of the car.

 

[echothreezero]

From reading the linked article I surmise the following:

When shorting the neutral circuit, the ecu still believes the car is in neutral after it is started and deactivats cruise control - you will probably have to jumper the auto circuit in the ecu connector instead of just the neutral switch.

then install the clutch microswitch.

I will be doing this myself in the upcoming months so if you can wait till then without cruise control I'll do a writeup once I have it sorted.

 

[jrt67ss350]

The cruise control is operated by a computer that is separate from the engine ECU. You probably need to just trace out the wiring from the cruise control computer to where it taps into the neutral safety switch wiring.

The engine ECU isn't involved in the cruise control setup.

 

[echothreezero]

Cheers for that - may save me some time. I havn't had a chance to look thru the Bentley. Will post back once i have done it - not on my high priority list as it car has a few other urgent repairs required first before I manual it.