I changed the passenger side drive shaft oil seal. Job wet reasonably well. Kept the brakes and hub on the suspension leg. Removed the drive shaft from the hub then gear box. Changed the seal and rebuilt it. 
since doing this the brake warning light comes on after I drive a 3-400 meters/ yards. Pads are fine, fluid level is fine. Disconnect the hand brake switch no change. Bypassed the fluid level sensor no change. Changed the ABS sensor on the side I worked on and reset it by removing the negative battery connector for over half an hour, no change. There is no pad level sensor on this car. Don’t really know what to do next, any suggestions?

30 minutes ago, S woods said:

Disconnect the hand brake switch no change. Bypassed the fluid level sensor no change. Changed the ABS sensor on the side I worked on and reset it by removing the negative battery connector for over half an hour, no change.

Wow !!

That was a lot of guess work.

You need to use FORScan and read the Ford specific DTC, which will tell why the ABS light is on. Logically it will likely be to do with the work that you recently did but proper diagnosis is required with Ford specific software.

On 4/7/2024 at 8:59 PM, unofix said:

FORScan (for use with Windows Laptop) : https://forscan.org/download.html

It's what many Ford owners use including some Ford technicians.

• vLinker FS, cable for laptop: https://www.amazon.co.uk/Vgate-vLinker-Adapter-FORScan-MS-CAN/dp/B0952P4MLP

OR

• OBDLINK EX, cable for laptop: https://www.amazon.co.uk/OBDLINK-EX-FORScan-OBD-Adapter/dp/B081VQVD3F/ref=sr_1_5

For diagnostic use only:

• vLinker FD, for android phone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H82WC8L
• vLinker FD+, for iPhone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H8JHWP2

 

Thanks. It’s not an ABS light . It’s the red brake light that goes off when you release the hand brake. Only mine decides it wants to come back on after around 300 yards ( when you in second or just into third).  Can’t really think of anything else other then putting it a garage at this point.

So it's the handbrake warning light meaning there's a wiring or (more likely) switch issue (or less likely BCM/GEM module)?
BUT  there's a lot of coincidence here i.e. you have done work on the brakes and now have a brake warning light
BUT BUT you worked on the front and it's handbrake/rear unless some wiring has been damaged.
Still a mystery needing either Forscan live data on handbrake switch or close wiring inspection, or taking it apart??

The garage won't be able to do anything that you couldn't do yourself with Forscan.

Red brake light without ABS warning is weird though I do think it will be an ABS wiring fault.  The only other brake wiring is for handbrake switch and level sensor and you've ruled both of those out.

5 hours ago, S woods said:

Kept the brakes and hub on the suspension leg.

You really need to deal with the fault urgently, "As a matter of life or death"

The time for randomly trying things has long passed, and proper investigation needs to be undertaken. Use FORScan and find out why the brake circuit failure lamp is illuminated.

My thoughts would be: Kinked or twisted flexi front brake hose, or even a nipped or crushed metal brake pipe. Carry out a very detailed inspection of all brake lines and hoses on and near the area where work was carried out.

Sorry, always wise to RTFM...So do we know what faults this warning light actually indicates please as it now looks very serious - where does it get it's signal from?

1 hour ago, Shearers said:

what faults this warning light actually indicates

We have to go back to the 1970's for a brief understanding of this warning light and how it has become thought of as 'just the handbrake warning light'.

When it was first introduced the warning light was only for low brake fluid level. Back in ~1975 I had a Mk2 Escort and it had a rocker switch which had the warning light. Pressing the rocker switch illuminated the warning light simply as a means of testing that the bulb worked. It was not at the time connected or associated to the handbrake. By the end of the 1970's the function of the warning light became both a 'brake failure' and a handbrake warning. This was had the benefit of testing that the bulb still worked every time the handbrake was applied. Over time many drivers have come to think of it as simply the handbrake warning. This is very much not the case. It's primary function is to warn the driver that one of the diagonally split brake circuits has failed and that the car should be brought to a stop gently and carefully.

7 hours ago, unofix said:

one of the diagonally split brake circuits has failed

You learn something new every day!

Our manual says this which isn't quite the same as Fiesta above:

I recall that there was perhaps a switch contact in the master cylinder which could indicate one of the brake circuits had collapsed and/or there used to be a float in the fluid reservoir to indicate a low level BUT I'm still wondering where the signalling information on this critical but nebulous fault comes from?
I can see no electrical connections to master cylinder or reservoir so the only possible way is from the ABS system by some method I can't visualise and why wouldn't it also put that warning on as well to emphasise the problem?

I would like to understand this and also find a resolution to @S woods issue?