Hill start assist problems

[J. Hewitt]

I am having trouble with hill start assist on my 5-speed manual 2013 Fiesta - it comes on spontaneously while driving. I am hoping to learn how to disable this feature.
The dealership says they cannot fix it because nothing shows up in diagnostics and it occurs too infrequently for them to pinpoint, and they "cannot" disable it for "safety reasons". I pointed out that it is a huge safety hazard to have it come on spontaneously while traveling, but ... rules are rules.

 

[Handy Andy]

IF you use your Parking Brake often - Read this thread...

https://www.fordfiesta.org/threads/manual-transmission-clutch-problem.7865/post-18121

This began as a "hung-clutch" problem but also morphed into a larger discussion of brakes and clutch and sharing the same reservoir between both and the headaches and possible cross - contamination of the ABS/Trac Control braking system and the Clutch Master Slave lines from debris caught in the lines.

The last post in the thread might help shed light on your condition - as it may reveal a clearance issue more from the tolerances the brake shoe to drum and the Brakes Parking Brake cable used to apply the rear brakes - there may be a clearance condition that seems to be more for the Hill-Assist, but might reveal line contamination and potentially requires a purge and refill of fresh fluid to alleviate the two conditions, one being the "loss of clutch control (Master Slave)" and the Hill-Assist condition causing dragging brakes on a subsystem as well as an adjustment to place more slack in the parking brake cable.

The Rear Brake piston and its adjuster might not have enough slack to release the shoe properly - it may be the main culprit.

 

[J. Hewitt]

Thank you very much.