Hi Guys,

90% of the time the stop start is displaying "Charging Battery" (i.e. sometime works for a short time). This improves after 400+ mile runs so I suspect the battery is on it's way out. BTW our company make chargers for batteries used in life safety equipment which we manufacture so we know quite a bit about charging them (we always replace batteries after 5 years as their performance will have deteriated). Unsurprisingly the local Ford dealer has told me it's all very complicated and the system has to be recalibrated etc., which it doesn't, unless of course Ford have designed it to be deliberately awkward to simply swap the battery for a new one of the correct type, which is entirely possible. They want to charge £240.00 to replace the battery (I can get the correct type of battery for around £100.00).

So my question is, has anyone had any experience of changing a battery, my guess is that the old battery will need to be disconnected and the car left without battery power for 30 minutes or so. When the new battery is then fitted the Battery Management System should detect that and everything should work OK, unless as I said Ford have deliberately made it uneccessarily complicated.

Thanks in advance.

Charles

take old battery out, put new in , and reset battery monitoring either through ford diagnostics, or diy sequence yourself.

The warranty on 'stop-start' batteries does tend to be lower, and the price higher, so, even with the improved construction of the batteries, the increased depth of discharge does tend to wear the batteries faster.

I've not played with the stop-start batteries in any meaningful way (although, just at the minute, I have a stop-start vehicle on my drive) but I don't see any reason to need to re-calibrate the system on fitting a new battery. AFAIR, the Varta recommendation is for any battery to be charged to at least 12.5 volts before being fitted to the vehicle.