ABS Master Cylinder / Pump Assembly

[DPDISXR4Ti]

I'm only just reading this thread for the first time today. I'm pretty sure the ABS function has never worked on this car. I've also noticed that the car pulls a bit to the right if you jump on the brakes. And most recently I've noticed some chattering/clicking when I first apply the brakes - I think I can even feel that through the pedal. Sounds like I should first try swapping in some relays.

Longer term, I'm somewhat inclined to just ditch the ABS stuff, which is what Noah's plate does, yes? I'm pretty sure that the power-boost function is retained when doing so. Noah? I'm also thinking you free up some real estate in the intake manifold neighborhood for when/if I ever get around to doing a MZR/Duratec swap.

[DPDISXR4Ti]

Regarding that mod...
Correct me if I'm wrong but is it not the case that when ABS fails (or this mod) you are left with just basic, non-power assisted brakes?

I was just talking to Noah about this and I believe you are incorrect in your assumption Dean. There is nothing electronically removed when installing the blanking plate. You still have the motor in place which is what provides the power-boost.

[brokencase]

OK, so the plate just removes the individual control to the brakes. It looks like his plate has holes on the side. Are there anymore detailed pics of the plate?

[Ed Lijewski]

"When ABS fails..." is too broad a description. If the pump and accumulator and pressure switch are functional but the ABS dash light is illuminated there is still power-assisted braking.

YMMV

[Ed Lijewski]

Re Noah's plate mod, TMK it hasn't been road tested or long-term proofed yet.

YMMV

[DPDISXR4Ti]

OK, so the plate just removes the individual control to the brakes.

I believe so, yes. Looking under the hood tonight, I think did mis-speak when I said nothing electrical is removed. The component that is removed, the Solenoid Control Valve Body, has that 7-pin connector going to it.

[my8950]

Re Noah's plate mod, TMK it hasn't been road tested or long-term proofed yet.

YMMV

There are a handful out and about being used. I will also put on in my other car at some point in the near future I hope.

The purpose of this is to just eliminate the ABS solenoids/mount. It does gain some room, but that is just a default.

[DPDISXR4Ti]

Question - does anyone know why Ford did not follow the standard DIN pin out architecture for the relays under the passenger side dash pad? The relay socket are easily 'modified' latter on to allow the use of standard replays. Note; the picture below is from my 1988, I believe the relay colour coding may have changed for 1989.

Ford often seemed to have their own format for relays; I suppose just because they could.

Just ran out and looked at my '89 parts car and the IAC diode and WOT relay are not there at all. The schematic indicates the IAC diode as connector C1902, but neither the '88 or '89 EVTM indicates location. Maybe they are in the fuse box on the later cars?

As you can see the locations are a little different. The circuit design is different. The orange ABS Electronic Control Relay no longer exists on the later cars. The green and one of the purple relays are the same function. I'm not sure what function is supported by that second purple relay on the '89 - I'm thinking it's unrelated to the ABS.

Scorpio1989Relays.jpg (413.98 KiB) Viewed 8546 times

[zxr250cc]

Hi all,

Were these same parts used on Euro Granada? Perhaps source parts from Germany or UK?

If this idea is really dumb, sorry.

Cheers

[brokencase]

Brad, I think the diodes are in the harness somewhere. Maybe you could do a check with the DMM to see if the diode is working (even though you can't physically locate it.

[Ed Lijewski]

'89 EVTM:

20230128_191002.jpg (1.94 MiB) Viewed 8509 times

YMMV

[DPDISXR4Ti]

Brad, I think the diodes are in the harness somewhere. Maybe you could do a check with the DMM to see if the diode is working (even though you can't physically locate it.

That was indeed my initial assumption - that the diode was in the harness near the IAC, just like it is with the XR4Ti harness. But now that Ed's image above has me looking in both the '88 & '89 EVTM, I see that the removable diode (same form factor as a fuse), should be in the same place next to the ABS relays regardless of the model year. I don't know what happened on my parts car - the whole C1172 blue block is missing entirely!

[DPDISXR4Ti]

I want to run a simple test and see what happens if I take the ABS function out of the equation but leave the hydraulic pump operational. I want to see if the random clicking and pulsing of the brake pedal goes away.

To do so I'm planning to leave Fuse 33 in place but remove Fuse 34 (Fuse 32 on 1989 cars).

Anyone see any issues with this? I think this is basically how people run this setup on a XR.

[Ed Lijewski]

I don't think relay clicking indicates ABS mode is activating on/off. More likely the accumulator isn't holding minimum spec psi or the pump seals are leaking or both.

I would put the pump assembly from your 89 parts car in your Blue Swimmer (assuming the parts car unit is there , and mileage on it isn't excessive).

FWIW I experienced pedal pulsing on brake application after installing two new front sensor cables. Haven't found out why yet. Even reinstalled original sensor cable(s) but the system still acted confused. (I stepped away from it for now.)

YMMV

[my8950]

I don't think relay clicking indicates ABS mode is activating on/off. More likely the accumulator isn't holding minimum spec psi or the pump seals are leaking or both.

I would put the pump assembly from your 89 parts car in your Blue Swimmer (assuming the parts car unit is there , and mileage on it isn't excessive).

FWIW I experienced pedal pulsing on brake application after installing two new front sensor cables. Haven't found out why yet. Even reinstalled original sensor cable(s) but the system still acted confused. (I stepped away from it for now.)

YMMV

But the brakes work properly? At least as much as you know...???