I have a C4 Grand Picasso Diesel Auto 1.6 2013 and only have done 7700 miles.
Suddenly the Start Stop function has stopped working. The ECO light flashes
three times and nothing happens. The battery is fully charged and noting is
draining the battery. I have already checked all requirements for the function
to work to be ok. I have a Autel Maxidas d708 and it throws error A4D4 Fault:
Rear door sills or boot lighting fault : Short circuit to positive ,
I have checked all connections and lights to be working and nothing appears
to be short circuit. However on further diagnosis I found that in BIS system
one item failed ( Number plate illumination control Actuation failed ), however
the lights are working. The DTC code comes back upon clearing.
I have travelled 100 miles without any electric item switch on, checked the issue
and it still remained.
I have switch on everything electric in car while engine is running, disconnected
and reconnected seat belts, switch off all electric devices, drove on motorway for
20 miles and yet still the Start Stop is not working, the green ECO flashes 3 times.
Every time I checked the ECU, it did had the code " A4D4 Fault:
Rear door sills or boot lighting fault : Short circuit to positive "
Please help. Thanks in advance.