Hi people! 

My 68 plate Ka+ stop/start has given up the ghost, died, not working etc 😁 its not the battery as had that checked at a car battery place as was going to replace it, but they said don't need to.  I've taken the car on a long drive (over 100 miles motorway & main A roads)  & it still didnt kick in when I stopped, so assuming its something else? Is there a sensor or something that needs replacing?  I know a lot of you think these Stop start things are as much use as a chocolate fireguard, so will it harm the engine or anything if I just leave it be & dont have it repaired?? 

Look forward to your opinions!

Thanks in advance

Julez

I say REJOICE!!!!

The stop start demands are high on the battery.  Just because it doesn't need replacing doesn't mean it isn't the reason for stop start not working.  Did the battery test provide you with results of the voltage and the CCA and the SOC?

There isn't a single sensor for stop start, it uses data from many other sensors around the car.  You would need to run a Forscan test to see whether any of those sensors are likely to be faulty.

It won't harm the engine if you don't have it repaired.

There are many things that can prevent the stop/start from working, this is a partial list of things that are required before the stop start will work:

- Vehicle speed is 0 mph.
- Accelerator pedal is released.
- Brake is applied
- Clutch Pedal in full TOP position of travel (Manual Transmission only).
- Brake Booster vacuum is present and a vacuum change does not occur while the vehicle is stopped.
- Gear selector lever in ‘N’ Neutral for Manual Transmissions and ‘D’ Drive for Auto Transmissions.
- Battery temperature is between 5°C (41°F) to 60°C (140°F).
- A/C system is OFF, or there is no change in the A/C system request while the vehicle is stopped.
- Road grade while stopped is less than 15%.
- All doors remain closed and the occupied front seats have the seat belt latched.
- In-car temperature is steady and no change is requested from the heating or A/C system.
- Engine coolant temperature is at the normal operating temperature.
- Max A/C or defrost is not selected.
- Blower fan control is at one speed setting and a speed change request does not occur while the vehicle is stopped.
- Rear defrost is not selected and a rear defrost request does not occur while the vehicle is stopped.
- Battery and charging system voltage is greater than 11.3 volts.
- Electrical load is less than 65 amps and a voltage or amperage load change does not occur while the vehicle is stopped.
- Steering wheel angle is less than 90° from the centre position and a steering input change does not occur while the vehicle is stopped.
- Hill Start Assist is not active.
- Automatic transmission fluid temperature is less than 110°C.
- Fuel Level is greater than 1/8 full and the low fuel warning is not active.

The most common item that usually prevents stop/start from working is a low battery state of charge. Driving the vehicle for hundreds of miles might not bring the battery SOC up to a high enough level, putting the battery on a smart charger for 12 hours might be enough to make stop/start work again if the battery is not too old.

It won't harm the engine if you leave the stop/start not working, in fact it might extend the life of some components.

7 hours ago, jooulez said:

so will it harm the engine or anything if I just leave it be & dont have it repaired?? 

Leave it well alone, it's not broke. As and when it feels like it, one day it will work again.

On the Ford Focus there are approximately 112 individual parameters that have to be "Just Right" before S/S works.

Similarly on the Ford Fiesta I believe there are approximately 108 parameters.

On the Ford Ka+ only the God Krishna would know 🤣

2 hours ago, unofix said:

On the Ford Ka+ only the God Krishna would know 🤣

Appropriate given its origins!😀

Thanks all .. much appreciated!!! 😁😁🤘🤘

Hi, do you also have the yellow warning triangle on the dash when it says stop start is unavailable?

No there's no warning or yellow triangle on the dash, but have found after stalling it does actually start again by itself, so obviously that part of the stop/start does work, just not at traffic lights, or when stopping in general! O well never mind!!! Lol