Apologies, first post. I have a 2010 Ford Focus Zetec 100 (1596cc) 5 dr manual petrol. Last week (just before MOT) the ABS light came  on and reduced acceleration message on dashboard - but no change in handling etc. Drove home and drove it again about 1 hr later - no problems, no lights etc.... ? dodgy connection. 48 hrs later, attempted pre-MOT checks ( lights, tyres, washers, horn etc ). On inserting key ( may be moved to position two - can't remember ) got scary engine malfunction error. As I had no way of diagnosing fault, switched off and tried to find mobile mechanic to diagnose/fix etc. no joy on mechanic, so resorted to internet, and found on various sites similar / identical scenarios, with solutions to get error codes/clear error codes and possible reasons  - tyre(s) problems, or fluid levels ?. So tried again  - started the engine - no lights nor messages !!!! so checked tyres , no apparent problems, but all low 26psi. all levels (oil,brake,steering) OK. Day of MOT and service - passed with two advisaries - side wall of rear tyre damaged but not fail, and delaminated reg plate. On picking car up informed that ABS light and message had come up x2 ( after MOT ) as part of road test in service. Error code was "communication error" ( hence the P1668 code - guess on my part ). It has come up once more since MOT/Service - but no loss of power etc ( as per first occurrence ). Three final things - (1) cleared itself again on stop/start. (2) while the message was displayed the dashboard display menu showed speed as 18mph, but actual speed 50 mph. (3) It is due cambelt change (over 10 years old and 88,000 miles - used to 100,000 miles/10 years ).

Should I be worried ?

Thanks

 

50 minutes ago, WaltsLookaLike said:

Should I be worried ?

No !

Concerned, Yes.

You need to use a proper diagnosis tool. Use Forscan software and load it on to a laptop (Windows 7 is better, but will run on Windows 10).

https://forscan.org/download.html    It's free.

You will need an ELM327 connection lead, there are many about but not all of them work well. Forscan recommend the lead from Tunnelrat Electronics.

https://tunnelrat-electronics.fwscart.com/USB_Modified_with_switch_ELM327/p4541936_17045457.aspx    £17.95

Then you will be able to find the cause of your ABS & Engine malfunction lights. The most probable cause is a faulty ABS sensor, but don't just guess use Forscan and read all the DTC's stored and it will lead you to the source of the trouble.

It is also very much worth checking the BCM & fuse panel behind the glovebox for signs of water and corrosion of the connector pins.

Many thanks for the very full explanation and checks to do. I will let you now the outcome