Switching to neutral with cruise control engaged

[ManniB]

Hi,

this is to make sure my understanding of the cruise control is correct.

When the cruise control is engaged and the clutch is depressed, a relay interrupts the signal from the control box to the servo until gears are switched and the clutch is engaged again. That is when the operation of the CC resumes automatically. Right?

When I switch to neutral and engage the clutch, the engine revs until red line because the control box has no clue that the transmission is in neutral!?

Is this really how it is designed?

Thanks, Manfred

[cgarr]

It should disengage while you push in the clutch but once you let it out it resumes so if it was in neutral the unit does not know that.

[GH85Carrera]

I only use cruise in 5th gear. Anytime I need to slow down or downshift I turn off cruise manually. I have never trusted the switches with my very expensive engine. Your engine, your risk.

[kodioneill]

I wired the cruise ecu so, when the clutch switch is engaged it shuts down the system similar to pressing on the brake pedal.

[schoward]

cgarr is correct it will resume once clutch is let off, basically assuming that you are going to another forward gear and it should continue to maintain set speed.

Just safer to kill the cruise with the brake pedal before messing with clutch and gears.

And in other words - Don't do that.

[john walker's workshop]

there is a micro-switch in the front tunnel with an arm that rests on the lever that the clutch cable is attached to. be sure the arm is still on the lever and the switch makes and breaks continuity.

[Autoban]

Manfred, I tested on my '86 Carrera and when in 5th gear pushing the clutch the engine goes to idle and when I re-engage the clutch the cruise control resumes the speed setting. Maybe the switch on your clutch pedal doesn't work?

Juergen

[ManniB]

Thanks to all of you to confirm my understanding of how the CC works. The rev-up in neutral is a "feature", or should we call it a design flaw?

Regards, Manfred

[john walker's workshop]

do you push in the clutch when shifting to neutral, or just pop it out of gear?

[ManniB]

Good question??? I think I pressed the clutch. I will verify, but it shouldn't make any significant difference since the CC brain has no indication that it's in neutral.

- Manfred

[kodioneill]

If you engage the clutch the cruise disengages, then you must have put it in neutral and let out the clutch pedal then the cruise reengages with no load.

[ManniB]

Originally Posted by kodioneill

If you engage the clutch the cruise disengages, then you must have put it in neutral and let out the clutch pedal then the cruise reengages with no load.

Yes, that is how I understand that it works and that is how it worked.

Thanks, Manfred