C4 Cruise Control Failure

[hertsnminds]

Went to use the cruise control today and it just beeped at me at the word SERVICE came up in orange letters (just under the seat belt warning symbols).

The LIM function was fine, just every time I switched to REG I got a beep and the service light.

Turned the engine off and on again and everything seems to be fine again. I hope it was just a one off failure requiring a reboot, that's the 2nd item for the 1,000 mile checklist. (the 1st was a lack of cover for the left side boot pocket).

Ian
Black 55 VTR+

[wozza]

I had the same service light come up and also the light about pollution or whatever it is.

Only had it once turned engine off and then on never had a problem since.

But did the pollution light come on for you as well?

[hertsnminds]

No pollution light just the service light.

Looks like any system fails and the service light comes on with the light for whatever system has failed.

It was just disconcerting as I had just pulled onto a motorway was doing 70mph and the SERVICE light came on, it went off as soon as I switched from REG to 0 or LIM, came on every time I switched to REG until after I had turned off the igntion and turned it on again.


Ian
Black 55 VTR+

[wozza]

See the pollution thing came up for me turned it off turned back on was fine.

Guess it just likes throwing up random errors. Wont be the only new car that does it.

Only problem with all these electrical systems giving warnings there a great idea but you get so many error messages that turning off and on fix.

[hertsnminds]

Managed to re-create the cruise control failure today. The common series of events was:

 

Fill the petrol tank

Leave the car unused for 24 hours

Drive the car and switch on cruise control

Service light comes on as soon as switch set to REG

 

To fix, just stop the car turn off ignition and turn on again.

 

At first I thought it was the road I was on (as it was the same as the last time) then I realised the car had been through a similar 48 hours prior to the last failure.

 

Ian

Black 55 VTR+

[wozza]

No polution light?

 

Only happened 1 time with me as i said and the polution light came on still same fix although took me a couple restarts.

 

You gonna speak to the dealer about it? Or just ignore it?

 

Probably just an odd sensor glitch.

[hertsnminds]

Probably ignore it for now and see if it gets any worse. If I can be more specific about what makes it happen then I will tell the dealer about it.

 

Ian

Black 55 VTR+

[Guest CE05LDB]

The Cruise Control on my C3 works Brilliantly. They have took the Cruise Control switches off the wheel now and put it on a sepertate stalk which I would find harder to use as I only got 1 hand on the wheel and the other on the Handcontrols.

 

The C4 would have come handy there are alot of controls on the wheel. The stere display screeb etc.

[wozza]

Cruise control is a bad thing really has turned me into a lazy driver the only time i actually drive the car myself now is when im goign for a bit of a more spirited drive. Otherwise i take great pleasure in getting in front of everyone and then sticking cruise control on at 30 quite funny how many people you can piss off sticking at 30 in a 30 zone :D

[ham's c4vts]

hi,

ive just brought a tomtom one and finding it very good at the min on short runs. I have found the the speedo in my c4 vts is spot on to the tomtom one speed reading at all legal speeds( all c4's must be the same), so 30 mph is 30 mph 70 is 70 mph. and i agree it does wind people up lol.

cheers ham

[wozza]

Yeah reading is pretty much perfect compared to my sat nav as well sometimes out by 1mph but nothing really.

 

But yeah some guy gave me a right load of abuse as he passed me today while i had the speed limiter set at 30mph in a 30 zone went flying past me just to then hit the red light and have to slam on his brakes. I bet he felt oh so much better than me for getting to that red light faster.

[hertsnminds]

I have the most fun on a road where there are lots of speed cameras eg A45 to the east of Birmingham. I set the cruise control and stay at a constant speed whilst others overtake and then slow down for a camera (to be passed by me) then they speed up again. Not sure why they bother.

 

Sometimes it does feel like you are speeding up and slowing down even though you are not. It is just when there is a hill and the engine pulls a bit harder (up) or is used to brake (down).

 

My GPS also matches the speedo readings to within about 1MPH

 

 

Ian

Black 55 VTR+

[wozza]

Must just be those digital dials i knew they were more accurate but not that much.

 

Just reminded me of when i went to scotland the other week. There was a section of the motorway with roadworks on 50 limit set my cruise control to 50 then those laser pointer things said slow down so i knocked it down to 48 to be safe. next minute guy goes past me around 100 mph to see 1 camera go off as he slams his breaks on and then goes through another one and triggers it.

 

Just made me think ha.

 

I was quite happy sitting doing my 48mph knowing nothing was gonna happen i didnt need to brake or touch anything except the wheel.

 

I just dont see the point in speeding up to then slam the brakes on. Just eating away at the brakes more when they dont need to be used and your not getting anywhere any faster.

 

When its safe to do so though cant say i dont speed i have had the car flat out once to see what it was capable of. But wouldnt drive like that constantly usually keep to 70 - 90 on the motorway. Althoguh have looked down to see it reading over 100 and i wasnt even aware i was going that fast i was keeping up with the traffic.

[ham's c4vts]

my mates MG 105 bhp (the little 214 rover) speed reads 76mph at 70mph on his tom tom one and thats got normal speedo

[wozza]

A lot fo the normal style speeds typically are around 10% out. My clio was the same.

 

The C4 matches the gps almost perfectly though.

[hertsnminds]

Interesting topic in the C5 technical section of this forum. WIth this link

www.psa-peugeot-citroen.com/en/psa_group/technological_files_b3.php

as to how the anti pollution system works in the Citreon/Pug diesel engine. The interesting point for me was the fact that after a fill up the system injects some catalyst into the fuel. I wonder if this cycle is what is causing the cruise control to fail. Maybe the cruise control will not work until after the cycle is complete and I am not driving far enough after the fill up for it to finish.

 

Just a thought and a reason why it would only happen to a diesel car.

 

Ian

Black 55 VTR+

[pork_pie]

The additive (not catalyst) is applied to the fuel to ensure all soot is burnt off.

 

(This was the next stage in emissions control after the introduction of Exhaust Gas Recirculation which served to reduce Nitrogen Oxide emissions).

 

This additive is called Eolys fluid which is held in a separate tank and blended with the fuel at a controlled rate. This lowers the boiling point of the soot there burns quicker An extra shot of fuel is applied to heat the cat enough to burn the soot off even more effeciantly.

 

The problem with diesel engines compared to pertol ones is that the combustive components are cooler (500c compared to around 900c so theres more solid/liquid compents to deal with.

 

Diesel oxidation catalysts are more rigidly built as theres an acid component of diesel emissions as well in addition to soot and other particulates.

 

The addition of filters reduce paticulates emissions to zero (but this adds cost and lowers MPG).

 

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Id put it down to a faulty sensor/switch somewhere thats confusing the ECU causing the engine to stall.

 

Check behind the pedals first.

[hertsnminds]

Id put it down to a faulty sensor/switch somewhere thats confusing the ECU causing the engine to stall.

Check behind the pedals first.

I don't have an engine stall problem, just the SERVICE light comes on when I turn on the REG, cruise control, after I fill up with fuel sometimes. Is cured by turning off the engin and turning it on again.

 

Ian

Black 55 VTR+

[hertsnminds]

Tried only filling to the fuel tank to the first cut off today and no problem with the cruise control.

 

So the fault must be to do with overfilling the tank and the diesel additive (eloys) cycle not being able to complete. Can't think of anything else as it only seems to happen to diesels and only after a fuel fill up.

 

 

Ian

Black 55 VTR+

[hertsnminds]

Can now discount the overfilling the tank theory as the failure is now occuring at least once per tank of fuel. Last time at about a 1/2 a tank and the time before at 1/4 of a tank. Also noticed the failure message which comes up on the radio display:

 

SPEED REGULATOR SYSTEM FAILURE

 

Have to say that you don't really notice the error message as your eye is drawn to the orange SERVICE light not down to the radio display and the message goes off after a couple of seconds.

 

The fault is still cured by turning off the engine and turning it on again.

 

Ian

Black 55 VTR+

[Stuey]

thats sounds like a trip to citroen to me mate...have you tried running the diognostic check that you access in the vehicle settings menu on the radio?? that might give you more info...

 

-S-

[wozza]

My diagnostic button is on the top of the dash next to the speedo.

 

But usually it only says if the cars got auto lights etc on.

 

Does it actually do something useful?

[hertsnminds]

The problem with taking it to a dealer is that the fault cannot be repeated on demand. I had thought the issue was to do with overfilling the fuel tank but now the fault has happened twice with a half empty or less tank. The other problem is even when the fault happens as soon as you turn the engine off and on again the fualt is cleared.

 

I still think is has to do with a sensor in the fuel system but don't want the car taken to pieces just to cure it. I will mention the problem at the 12,500 mile service and see what is said.

 

And I agree that the CHECK button just tells you stuff you already knew, auto wipers/light on/off etc nothing particularly useful.

 

 

Ian

Black 55 VTR+

[lee_marshuk]

@hertsnminds

 

I've been meaning to post this for a while.

 

I too have been having the intermittent failure - exactly the same as you, but it isn't anything to do with overfilling the tank/filling etc.

 

I took it to Citroen and explained it - took the line of "I don't care if I can't replicate it its happened at this time this time and this time and when I've spent this much money on a car you can give me a courtesy car until you fix mine" - it worked! They plugged my car into the diagnostics machine and went through the event logs. Problem with mine was a dodge clutch sensor (as you know, in cruise control mode pressing the clutch pedal de-activates it). Straightforward replacement apparently.........

[hertsnminds]

Thanks Lee that's brilliant, I have to admit it was starting to get annoying. Now I can tell the dealer exactly what to check for and don't have to take any BS as I know there is at least 1 other owner who had the same problem.

 

Thanks again

 

 

Ian

Black 55 VTR+