e-HDi eco mode battery voltage

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onix45
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e-HDi eco mode battery voltage

Post by onix45 »

Hello,

Does anyone know at what battery voltage the start-stop function stop working because the battery is considered too low?
For some reason i think it was 12,5V but i am not certain.

Or is it related to the battery charge percentage? I do recall the threshold being 75% cahrge, but surely there has to be an equivalent voltage for 75%?
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GiveMeABreak
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Re: e-HDi eco mode battery voltage

Post by GiveMeABreak »

I think it's a little more involved than that to be honest. For example, when operational, the system will automatically restart the engine in the following conditions:
  • Inadequate vacuum reserve
  • Vehicle speed above 8 km/h for a vehicle fitted with a piloted manual gearbox
  • Vehicle speed above 25 km/h for a vehicle fitted with a manual gearbox
  • Lowering of the temperature of the Lambda sensors
  • Thermal protection of the alternator
  • Thermal protection of the battery
  • Thermal protection of the voltage retaining device ECU
  • Battery charge status below 73%
  • Battery charge status becomes non-nominal
  • Battery voltage below 11,8 V for 1 seconds
  • Power accumulator voltage below 4,7 V
  • Engine requirement (*)
  • Power steering system downgrade mode
If the following are true then the engine will not start automatically.
  • Traction chain closed
  • Power accumulator charge status inadequate
  • Low battery charge status
The Stop Start will not stop the engine if the battery charge status is below 75%, you have undertaken 6 stops in the previous minute or a host of other factors.
If you have a fault or warning light there will be a fault code you can read with Lexia - that will help us with diagnosis.
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onix45
Posts: 45
Joined: 06 May 2017, 11:52
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My Cars: C4 2013 eHdi 1.6
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Re: e-HDi eco mode battery voltage

Post by onix45 »

Nah, its fine, it just wont stop the engine. because the battery is pretty old. I drive most of the time in the city, but it used to be that after driving out of town somewhere the start-stop would start to engage again for a day or two. But now this is not the case anymore, even after a long journey. So i am just wondering if it is time to change the battery. The car starts fine and there are no other signs of a weak battery, but i will see what happens when winter comes and i'll have to start it in the morning.
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GiveMeABreak
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Re: e-HDi eco mode battery voltage

Post by GiveMeABreak »

Ok, these are the conditions that have to be met for the engine to stop when using the system - there are USER conditions and SYSTEM conditions:
User conditions allowing the engine to be stopped:System conditions allowing the engine to be stopped:
  • Stop and start function activated
  • Cabin temperature corresponding to the driver’s requirement
  • Brake pedal applied or changing into neutral position with a vehicle speed below 6 km/h (Piloted manual gearbox)
  • Gear lever in neutral, clutch pedal released and vehicle speed below 20 km/h (Manual gearbox)
  • Driver’s belt fastened
  • Driver’s door closed
  • No pressing of the accelerator pedal
  • No deicing/demisting of the windscreen
  • Electrical power sufficient to permit restarting of the engine
  • Vehicle speed has exceeded 10 km/h since the initial starting
  • There has been an interval of at least 4 seconds between 2 engine stops
  • There has been an interval of at least 2 seconds since the previous restart
  • Adequate vacuum reserve
  • Fuel temperature below 60°C
  • Alternator temperature below 130°C
  • Battery temperature between -5°C and 60°C
  • Power accumulator temperature below 55°C
  • Voltage retaining device ECU temperature below 90°C
  • Battery charge status above 75%
  • Fewer than 6 restarts per minute
  • No regeneration of the particle emission filter in progress
  • Power accumulator voltage insufficient(4,7 V)
  • Internal resistance of the battery below 5,6 mΩ
  • No regulation by the dynamic stability control system
  • Exceed 10 km/h after application of the electric parking brake
  • No power steering system downgrade mode
  • Altitude below 1700 metres for vehicles fitted with the DV6C engine and a piloted manual gearbox
  • Absence of engine requirements (*)
Please Don't PM Me For Technical Help

Marc
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