kim0785b
Member Since: 12 Feb 2021
Location: London
Posts: 135
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![2015 Discovery 4 3.0 SDV6 SE Auto Santorini Black 2015 Discovery 4 3.0 SDV6 SE Auto Santorini Black](../images/veh/santorini_black.gif)
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Start-Stop Battery suddenly come alive |
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Start-Stop never really worked on my SDV6, however the other day when driving around in a fair bit of city traffic the Aux battery kicked-in and suddenly the Stop-Start function was restored after a year!
Is there something about driving lots of short distances that seems to replenish the aux battery that has revived it perhaps?
next step would be to switch it off when getting in the car.... Discovery 4
Oct 2015, 2016 build
SDV6 Santorini Black SE
New engine at 42k
Car camper
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21st Nov 2023 4:42 pm |
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Gary_P
Member Since: 03 May 2016
Location: Kent
Posts: 1583
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If the eco stop start warning light was not on, then the issue with your stop/start was most probably down to main battery charge level which has to be well charged in order for stop/start to work. Gary
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Discovery 4 HSE 2016MY
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21st Nov 2023 6:16 pm |
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Sparky791
Member Since: 06 Dec 2023
Location: Northampton
Posts: 1
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The normal issue with Stop/Start is the Cold Crank Voltage (CCV), this is nothing to do with the battery directly but more the calculations done by the Battery Monitoring Sensor (BMS) which is fitted to the negative post of the battery. This calculation is and aways was a problem, the figure started at 7 volt and has been reduced over the years to 1 volt, in the Gateway module software.
The BMS needs to see current (Amps) going into and importantly out of the battery, so a vehicle that is used mainly for long trips will very quickly loose the function or it becomes annoyingly intermittent.
If the system stops functioning due to the battery just get the issue confirmed, but if the vehicle still runs there is likely nothing much wrong with it, a battery test WILL NOT identify the CCV as an issue as the tester cannot see the information from the BMS, unless the battery fails a battery test DO NOT REPLACE IT. You can confirm if this is the issue by simply disconnecting the battery for 5 minutes and re-connect it check if the system starts to work. If it does work its a good indication the CCV is low, you can regenerate this by starting the engine let is stabilize and then turn it off within 20 seconds, repeat this 3 times, once or twice a week (provided you are doing trips over 20 to 30 minutes, provided all the other 200 odd parameters are ok the system will come back on line. Remember the system will not function in cold weather or if the A/C is being used or the fan is at max speed.
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6th Dec 2023 2:57 pm |
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