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My cruise control has never worked and has niggled me for ages, so I decided to investigate and I am feeling quite smug as I have managed to fix the problem.

The switch on the clutch that operates cruise was not contacting the clutch pedal - when the clutch pedal is up the switch should be depressed. I was told I'd need a new switch, so thought there would be no harm in taking it out for a look - after all, if it didn't work I could hardly break it more.

First I stuck myself upside down in the footwell with a torch for a good look. The switch is located right at the top of the pedal in a square bracket. I got hold of it and turned 90 degrees clockwise (lucky try in the correct direction first) and it popped out. Then I disconnected the wires at the non-clutch end and the switch was free!

I carefully prised the two halves of the switch apart with a small flat screwdriver. Inside the clutch-side half there is a plunger with a spring over the top of it. The end of the plunger sticks out the end of the switch and is supposed to be depressed by the clutch pedal. My plunger didn't stick out far enough, but when I looked closer I saw there is a circlip holding the plunger in. I removed the circlip, out came the plunger and to my surprise it had threads in the middle. The threads allow you to alter the amount the plunger sticks out by, so I replaced the plunger, sticking out by a couple of threads more, put the circlip back in, put the switch back together and put it back in the car. Now my plunger contacted the clutch... so far so good, took it for a quick test drive and tah daahh! Working cruise control.

I hope this helps someone else!

Now I have to change my sidelight bulb (which has a broken holder) and stop my driver's door leak, but one thing at a time...

Cat
 

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Had my 147 a year but never bothered with the Cruise Control - following reading your post I tried selecting it - However nothing - no warning lights or anything - Is this the same that you had?

I will check out your fix thanks - Once the damm rain stops that is :thumbs:
 
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Had my 147 a year but never bothered with the Cruise Control - following reading your post I tried selecting it - However nothing - no warning lights or anything - Is this the same that you had?

I will check out your fix thanks - Once the damm rain stops that is :thumbs:
If cruise doesn't work, the pedal switches are the most common cause of failure, the brake light switch is the most common of the two as well.

FES can tell you why the system isn't working, on mine it was the brake switch which gave implausible signals according to FES.

The brake switch is £15 from Alfa. The clutch switch is £60.
 

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Many Thanks AndyMac

Recently I had the codes read due to a faulty Crank sensor - also logged was brake pedal switch fault - so that may be the reason for the faulty Cruise Control ;)
 
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Does the brake pedal switch have a duel purpose as my brake lights operate ok?
Yep. The brake pedal switch has a multi connector. On mine, the brake lights worked fine, but the cruise didn't work. Swapped in the new switch and it started to work fine. No idea what was going on inside the switch because it seems to be a very simple thing, like a big plunger in a tube. It's a simple fit to, the old one needs turning 90 degrees and pulling out upwards, the new one goes in the hole and twist to lock. Mine was really stiff, I borrowed an old bath tap fitting spanner to fit it.

As an aside, my last 3 cars with cruise all needed new brake switches to get the cruise working, so it's a common fault of various brands. Mine were Audi A4, Fiat Stilo and Alfa 156.
 
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May find that cars that have had the clutch master cylinder replaced at some point also don't have working cruise control as the switch hasn't been reset.

I found this out after doing the master cylinder and wondering why my cruise stopped working. Although I didn't take it apart, I just pulled the piston out with a pair of pliers as it's on a ratchet :lol:
 

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Discussion Starter #10
Had my 147 a year but never bothered with the Cruise Control - following reading your post I tried selecting it - However nothing - no warning lights or anything - Is this the same that you had?

I will check out your fix thanks - Once the damm rain stops that is :thumbs:
Good luck with it Lesmott.
My dash light for cruise would sometimes appear and sometimes not, so initially I thought it was the usual dodgy Alfa wiring.

Initially when I pulled the switch off I tested it by hooking it up to a lightbulb and a battery, and it didn't work, (the bulb should have switched off when the plunger was depressed) so when I disassembled it I had a look at the contacts, and there is a little metal plate inside the switch which gets pressed down by the plastic plunger to break the contacts. The plate was bent so I straightened it out and reassembled it and tested it again, this time it worked so I assume that was the problem. Then of course I had to disassemble it again to change the plunger position.

It's all still working nicely so I assume that reassembling the switch fixed the issue with the dash light too...!

I am glad I bothered to fix it as AndyMac says above they are £60 from Alfa - that's £60 I would rather have in my pocket, thanks!

Hope the fix works for you with the brake light switch.
Cat
 

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Thanks all - I will take a look at the weekend - marlon my master cylinder has been replaced so I will give it a go as you suggest. Never had Cruise Control before but I do a 60 mile a day mainly motorway so worth using

Thanks all :)
 

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Just took my clutch switch out using your advise. My plunger also doesn't stick out far enough. Could you elaborate on how you adjusted it using the treads??
 

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The plunger/pin can be adjusted without removing the switch, simply hold the clutch pedal down and pull the pin out with pliers, it's what it's designed to do, the pin will self-adjust its position when the clutch pedal is released.

The problem arises when/if the split pin that connects the clutch pedal to the rod of the master cylinder lets go, the clutch pedal is now free to travel higher than intended pushing the pin too far in.

All the best

Pub
 

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The plunger/pin can be adjusted without removing the switch, simply hold the clutch pedal down and pull the pin out with pliers, it's what it's designed to do, the pin will self-adjust its position when the clutch pedal is released
+2

You've got to give it a solid tug, which feels a bit too much for it, but it'll pop back out into the right position and start working instantly.

ROCK ON
R~R
 

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I've not had a chance to test it yet but thanks for the tip, I adjusted the switch on my clutch as per guide above and it not reaches the pedal so fingers crossed will work, much appreciated.
 

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I've just done as Fastestcat explained and now I have no more ASR/ABS/VDC errors and now my Cruise works! :D
 

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The plunger/pin can be adjusted without removing the switch, simply hold the clutch pedal down and pull the pin out with pliers, it's what it's designed to do, the pin will self-adjust its position when the clutch pedal is released.

The problem arises when/if the split pin that connects the clutch pedal to the rod of the master cylinder lets go, the clutch pedal is now free to travel higher than intended pushing the pin too far in.

All the best

Pub
Absolutely spot on - my split pin let go - easy fix [keep one of those very large paperclips in the car as an emergency get you home fix - exactly right diameter and soft enough to twist & break as required] - properly fixed with a split pin once washer retrieved from behind foot rest. Cruise stopped working and needed its plunger withdrawn. Tried the "depress the clutch pedal & withdraw the plunger with pliers" - worked for me - let the clutch pedal go slowly to avoid whacking the plunger too deeply into the switch.

IB:thumbs::thumbs:
 
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