Start/stop Problem.

[Barneydoc]

Hi. I'm new here and am currently finding my way around.

 

I have had my C5 diesel auto (2010) for over 3 years now and have had absolutely no problems at all with it until now. I love it and only regret I never owned one before!!!

 

My problem is relatively minor but is having a massive impact on my fuel consumption.

 

I'm finding that the stop/start feature (it's an E-hdi) only seems to work from time to time. Due to the winter temperatures, I thought it might be something to do with the cold. Now the temperatures have risen it seems this is not the case.

 

Is there a fix I can perform to sort this out or is it a visit to the dealer? Thanks in advance for any help in this.

[madmadmax]

if your battrey voltage is low it will have an impact on the start stop, it may be somthing compleatley diffrent tho. so check your battrey and then get it on a lexia and check all is ok

 

things to chek are

battrey voltage when running and switched off

check wiring see if it looks chafed or cut

 

air conditning gas presher (can be done with lexiea)

 

thats about as much as i know about start stop tec but some one will be along to add stuff no doubt

[paul.h]

There is a list of things in the handbook that prevent the stop/start working so the battery does not go flat - have a look and see if any apply such as using lights/heating/air con/maybe it is switched off and not resetting/as noted above a low battery voltage - are you doing short trips ?

[Barneydoc]

Thank you for that. I do take a lot of short trips.

 

I will check those things.

 

Thanks again..

[Barneydoc]

I have checked the voltage on the battery. It's at around 12.5-13 with engine off. When I switch the engine on it doesn't change very much. Does this point to the alternator?

[paul.h]

The engine off voltage seems normal but with the engine running the battery voltage would normally be about 14.2 volts but with a stop/start car I am not sure if it would be different. If your alternator was not working then the battery would likely go flat quickly.

 

So if these are both ok then possibly a sensor is faulty but to check these a dealer visit may be needed.

 

A recent C3 topic on stop/start found there is a second battery under the front passenger seat so you could have a look and check its voltage.