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[Craig_R]

I am waiting on a Cruise control unit that sits in the engine bay

After Reading a post by Gary he said his cruise control system only needs a 2 pin brake switch.

I have had a horride thought that the Cruise system I am waitning to be delivered might be one of the ones that only needs a 2 pin brake switch when mine has all the wiring for a 4 pin brake switch.

Will a Cruise control box work with a 2 and 4 pin brake switch or are there different ones for different brake switchs ie 4 Pin ans 2 pin

[colalowe]

I think that the box is the same for all the cruise systems and the difference in switches is due to whether you have a manual, in which case there should be a switch on the clutch and brake or auto which is just the brake, it may need switching on with tech 2 as well?  

Im not sure to be honest and may have just talked a load of crap!!

Im sure someone will clarify soon.

[Paul M]

You'll probably need to swap it for a 4 pin brake switch. That's what I had to do, as well as fit a clutch switch. Alternatively you can solder a relay onto the wires, which will make a 2 pin switch behave like a 4 pin one. Depends on whether you can be bothered with the hassle -- I opted for the easy option!

No need to enable it with Tech2 on 2.0, 2.5 or 3.0 engines.

[jonathanh]

Stop having horrible thoughts and relax!  All cruise modules will need a 4 pin switch to be properly installed.

I had to study the haynes wiring diagram a lot to get my cruise module working, even then my wiring loom is different.  Anyway, here is my take on how things work.

A standard 2 pin brake switch is a press to make switch, a 4 pin switch is a combination of press to make and press to break.  Also, where fitted the clutch switch is press to break.

From a safety point of view it makes lots of sense to operate the disengage switches (brake, clutch and 'O' switch on the cruise stalk) on the press to break principle: if anything at all goes wrong like a dodgy connection, switch failure etc the unit disengages.

Suppose now that the VX built a cruise control system that relied on the 2-pin press to make switch, let's then assume that the brake fuse failed so there was no positive supply at the switch:  result is that the cruise system would not dis-engage.

Here's where the confusion can start:

The cruise module not only takes a feed from its own 'press to break' brake switch but it also senses the normal brake light circuit.  So you CAN use a 2-pin brake switch and it will disengage the cruise module but to get the unit to work in the first place you need to modify the loom to ensure that the unit believe that there is a 4-pin switch fitted (i.e. that there is a +ve feed on the pin that the unit uses to detect the brake pedal is not pressed).  


My view is that I would install a 4 pin switch as the second circuit is there as a safety feature.  

Good luck and keep us posted

[ffcgary1]

Craig, you do not have to have a four pin brake switch to make it work on all models,unless your car has four wires going to the brake switch, which if i remember is so in your case.In that case you do need to change the switch. I have just installed 2 systems into 97 model cars ,ONE auto,ONE man,both had 2pin brake switches and both work as they should.the only additional switch i fitted was to the MAN car and was a 2 pin clutch switch.Dont take too much notice of the haynes book of lies use only as a ref not gospel.Even vx dont know what their cars have fitted to them.If you want a 4 pin switch contact me as i have one avalible.  Gary.

[Paul M]

The cruise module not only takes a feed from its own 'press to break' brake switch but it also senses the normal brake light circuit.  So you CAN use a 2-pin brake switch and it will disengage the cruise module but to get the unit to work in the first place you need to modify the loom to ensure that the unit believe that there is a 4-pin switch fitted (i.e. that there is a +ve feed on the pin that the unit uses to detect the brake pedal is not pressed).  

If it's press to break you can make it work by shorting out the two extra pins. I do not recommend doing this though, just in case there's a failure with the other half of the brake sensing system as mentioned. I done a similar thing with my clutch switch connector when I was waiting for the clutch switch to arrive. So I could test the system I just bridged the pins so the system would thing the clutch pedal was always unpressed. Worked fine, the only risk was if I pressed the clutch while cruise was engaged, it wouldn't disengage so the engine would race to the rev limiter -- in theory at least, I never tried it. I properly installed a clutch switch a few days later and it cuts out as soon as the clutch is pressed, as it should.