Brake warning problem.

[Pug957]

Hi guys.

Got an issue with my van. Basically the brake pad wear warning is permanently on.

The wiring was damaged a few years ago and the local Ford repair was simply to short the wires out conning the system into thinking that pad was always ok.

Fast forward to today, the van is out of warranty and it has started acting up because the wire itself is corroded giving enough resistance that the computers think the pad has gone too low. I would cut the wires back further but that would mean running the risk of damaging the abs sensor wiring now as there's only about an inch of individual wire, that's corroded, exposed after their bodge.

So the question, does anyone have a wiring diagram or know the pinout and which module controls the warning so I can do a better bodge than Ford?

Thanks in advance.

[TallPaul]

Is the problem between the connector and the pad, if so just buy another sensor and stick it on. Assuming you’ve thought of that and its further upstream, I cant see a problem with cutting out the damaged section and just soldering in a new length of wire. I’m pretty sure it doesnt rely on resistance it just goes straight to earth to trigger the warning lamp.

[Pug957]

The wire is chassis side of the connector. The abs and pad wear wires run in the same 4 core cable. The cores are then exposed a few inches with a seal glued on to prevent water etc getting in. The exposed cores are a couple of inches long to the connectors which the abs and wear sensors plug in. It's that exposed bit chassis side that's damaged.

I am careful with stripping back wiring but if I accidentally damage the abs wiring it's a whole different world of pain to sort out. Because of this I want to make the bypass at the module to prevent further issues reoccurring.

I know the sensors are essentially a ground loop but the circuitry often works on voltage levels. A 5v system could see anything below 2.5v as "ground" and anything above 2.5v as "+5v" at a logic level.
I tested the voltages at the bare wires for the sensors and the damaged one is much lower than the good ones. This can force the unit to see a higher voltage and think the pad is duff. The reading also suggests there's a lot of corroded wire in that run meaning I may have to go a good meter plus down the loom for an effective repair from past experience.

Sorry if I seem off here, I'm not. Just been a long day and I may not be wording things right.

[TallPaul]

To be honest you've gone way past my level of knowledge there! Out of interest how did they get damaged? I've had the cable rub through against the wheel if its not secured but its between the pad and the connector, not the other side.

[Pug957]

The ford dealer ripped it off when changing the pads

[Pug957]

I wish that was true

We do a lot of work on building sites, quarries, landfill sites etc and put the vans in places that would make people cry. Something caught it whilst reversing and ripped it off. Just grateful the pad wear was the bottom plug and not the abs sensor.