Recently, whilst trying to diagnose a DPF issue, I cleared the codes using a mobile phone code reader linked to a bluetooth OBD reader. As soon as I pressed the OK button to reset the DTCs the car made the bing-bong fault noise, the dash displayed a yellow dot on the nose of the car with the message "Front lights malfunction". 

The car had never displayed this fault before, and the lamp level testing has always worked prior to this. It seems to much of a coincidence timing wise that it isn't related to the resetting of the codes, as it was immediately after pressing the reset button.

Could this have been caused by the program I used? Genuine fault or introduced a bug into the system?

I have since downloaded FORscan and plugged it in, and I get the below info;

===HCM DTC C1A05:14-AF===
Code: C1A05 - Left Rear Height Sensor

Additional Fault Symptom (:14):
 - Circuit Short To Ground Or Open

Status (-AF):
 - DTC Present at Time of Request
 - Malfunction Indicator Lamp is On for this DTC

Module: Headlamp Control Module

 Freeze Frame  #1:
-EVENT_TIME: 358351576 s - Event time
-TOTAL_DISTANCE: 153148 km - Total Distance
-MODULE_VOLTAGE: 13.3 V - Control Module Voltage
===END HCM DTC C1A05:14-AF===

 

 

Any joy with this same thing happened to myself

Did you also reset DTC's with some scanner?
All I can say is, if Forscan says "short to ground or open" then it is monitoring official Ford codes so that needs looking into and checking - let us know if that fault is genuine?