Technical No cruise control

[XB23]

Hi all

Ok so I've just had a new clutch fitted however I've just noticed that now my cruise control light won't come on even if the switch is on

Light comes on when car starts but goes off but won't come on when the cruise control is activated

Any ideas?

 

[Davren]

Possibly whoever fitted the clutch has disturbed the D4 connector under the engine fuse box when removing the gearbox.
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[XB23]

Possibly whoever fitted the clutch has disturbed the D4 connector under the engine fuse box when removing the gearbox.
.

Is that something I can easily solve myself?

 

[Davren]

There's a guide to cleaning the D4 connector here: https://www.fiatforum.com/stilo-guides/99828-d4-connector.html

Check that all the connections through it are secure and making good contact. There's also another similar connector in the same area.
.

 

[XB23]

There's a guide to cleaning the D4 connector here: https://www.fiatforum.com/stilo-guides/99828-d4-connector.html

Check that all the connections through it are secure and making good contact. There's also another similar connector in the same area.
.

Tried cleaning d4 but still no luck

The green light comes on when first switching on ignition but won't come on after that, also noticed the radio has stopped switching off when ignition is turned off

Any ideas? By the way my clutch problem is sorted now so that's good lol

I'm sure a min ago it did activate for about 2 secs then came off again it's annoying!

 

[XB23]

Tried cleaning d4 but still no luck

The green light comes on when first switching on ignition but won't come on after that, also noticed the radio has stopped switching off when ignition is turned off

Any ideas? By the way my clutch problem is sorted now so that's good lol

I'm sure a min ago it did activate for about 2 secs then came off again it's annoying!

Update : radio issue now fixed just wish I could enable bloody cruise control lol

 

[Davren]

Check fuse F35 (7.5 Amp) in the dashboard fuse box.
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[XB23]

Check fuse F35 (7.5 Amp) in the dashboard fuse box.
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Yep fuse is all good any other ideas?

 

[rugbymike7]

I don't know how similar stilo is to a alfa but on my 147 cruise control didn't work because of a switch on the clutch pedal. There is one on the clutch and one on the brake. If either aren't making full contact cc won't work. They cost about a tenner and are a 5 min job to fit.

 

[XB23]

I don't know how similar stilo is to a alfa but on my 147 cruise control didn't work because of a switch on the clutch pedal. There is one on the clutch and one on the brake. If either aren't making full contact cc won't work. They cost about a tenner and are a 5 min job to fit.

All fixed I hooked it upto multiecuscan and some faults about breaking light and clutch switches shown up so cleared them and like magic it's working now!

 

[XB23]

Brake light switch

Hi all

My stilo keeps disabling the cruise control because of a brake light switch fatal error according to the ECU

Weird thing is my brake lights are working perfectly but this fault keeps coming back on the ECU

If it's the switch how are the lights still working? Will replacing the switch fix it?

 

[rugbymike7]

Re: Brake light switch

Yeah it will. On alfas the brake lights will still work as normal but cause cc to not work and Vdc errors changing the switch usually cures it. You could try removing yours a pulling it out and in a few times to see if you can free it.

 

[richydraper]

Re: Brake light switch

im pretty sure if the brake and accelerator pedal are depressed simultaniously it throws a 'fatal error' fault for the brake light switch.

its a scenario which the ECU is programmed to think should never happen. if you accidentally press both pedals it throws a fault. it can be simply due to a maladjusted brake light switch. if its not that and it turns out to be your switch at fault then you can buy a switch for around £10 iirc from fiat.

there are 2 individual circuits on the brake light switch, one for a direct feed to the upper brake light and one to the BC which controls your lower brake lights (the BC feed is also the feed that triggers the fault as you've mentioned and tells the engine ECU to deactivate the 'cruise' signal)

 

[XB23]

Hmm but wouldnt that mean the lower brake lights wouldn't work if this was the case? or am i misunderstanding?

 

[richydraper]

everything would still work... the ECU won't stop the brake lights working, what you will probably find is that as soon as you touch the pedal the lights come on, there should be slight travel in the brake pedal before the lights illuminate, what can happen is your brake lights are staying on after you release the pedal when driving. as you press the accelerator pedal again the ECU throws and stores the fault but it will still allow your lights to work.

to adjust the brake switch push the brake pedal down as far as you can (turn the engine on to get the vacuum assist to help you out ) and pull the switch piston down firmly, you might want to use some long nose pliers. you will hear it repeatedly click, this is normal as the ratchet mechanism resets. once fully pulled down just let the brake lever go, it auto adjusts so there is no need for any further adjustment... EASY right? check brake light operation again there should be around 10-15mm of pedal travel before the lights come on, if after adjustment it still comes on as soon as you breath on the pedal then its probably time for a new switch. whilst i think about it don't pull the pedal up at any point as this throws the switch adjustment out and you'll have to start again, sometimes you can accidentally hook your shoe under the pedal and lift it, if you notice you've done it then reset the switch.

ive never heard of the fault turning off the CC system, so that there is no light on the dash, but you say without the faults in the ECU it works normally. so we all learn something new everyday :lol:

 

[XB23]

Interesting thanks for the info..

Dont know if makes a differnce, but on multiecuscan you can watch certain functions of the car working.

eg, Clutch pedal switch, Brake light switch.

When the clutch is pressed, its says 'Pressed' and then when let go 'Released'

The brake pedal one never changes always says 'Released'

the error says Fatal - Invalid Signal?

 

[richydraper]

new switch it is! sounds like the internals have failed... iirc the replacement switch is on a 'supersession' number from fiat. i.e. they found a fault with the original design and modified it. probably the internals failing

 

[paullawton2007]

hhmm i think im having the same problem with c/control. brake switch circuit b. is this the same problem you are having?

 

[XB23]

nope the fault im getting is definatley brake pedal switch not circuit

maybe its switch related as well? i guess the switch is part of the cicruit

 

[paullawton2007]

dont know if this will help. check your Black D4 (Next to the brown d4) under the battery fuse box. check if A02 is connected. some need a perm 12v.

im gonna try this ina bit to see. just a thought? or was it working and its stopped

Paul