2009 Ford Explorer - Low Brake Fluid warning Light On - SOLVED

Starting Caveat - I am mostly a GM guy, who occasionally works on fords, wiring/troubleshooting is my wheelhouse, I enjoy it (yes I know, i'm crazy. :blink: )

VEHICLE INFO:
2009 Ford Explorer
4.0L V6

Issue: Park brake light on dash is on and low brake fluid warning message is on.
Backstory: Vehicle came in with an abs module with an internal fault code, only a handful of modules were showing up on forscan...module was taking down part of the CAN network...unplugged module, all other modules came back online. got replacement (salvage yard) module given to us by the owner to install and get programmed. did that, had above issue...checked switch functionality, wiring and ground between switch and abs module (using powerprobe, meter, test light etc.) all good, can light a test light (loaded circuit test). Next pulled diagrams for abs connector (all-data) and checked all my power's and grounds (loaded/test light) were good to the abs connector. using forescan I was able to verify the park brake switch is good, watching PID it would go from showing on/off when e-brake was depressed vs not - so that wiring is good.

I know the fluid level sensor circuit is a pull-down design (3-wire, 2 wires in/out from abs module when fluid goes low and switch trips it pulls the circuit to ground via 3rd wire).

1st Question: I can't seem to find in alldata is what my voltage on that circuit should be to begin with (is it 12v ref, 5v ref, 2-3v low/bias voltage? if I recall I believe with the circuit unplugged at the switch (after verifying my wiring) I had voltage in the 2-3v range.

2nd question: anyone have any gee whiz (try checking this) ideas/info...my next step is to tear into the dash to get to the smart junction box and start testing every wire/circuit between the abs module and it (after I check a couple specific ones that Ford's troubleshooting matrix says to check first)

Any help greatly appreciated...I will not let this sucker beat me. :S

The switch should see more voltage than that
(12v). first check to see if you have a solid ground with the multi meter. Then check each one again Also check the float in the reservoir to see if it is stuck down. A pick or awl should work to free it if it is stuck.

Well, if it's definitely supposed to be 12v then I need to start tracing /checking wires between module and Smart Junction box etc, because I've checked my power's ground's and fuses/relays to the module connector and they are good. Switch is good, wiring from switch to module is good. fun times, I'll keep thread posted with what I find.

Little late of a reply, been going out of town for work a lot (headed back out today) but I was able to solve the issue. after much tracing of wires and fixing of wires (previous owner had done a hack job of installing a remote start unit.) I still had the same problem...so I decided to take a look at the ABS module harness...someone had repinned #39 wire (goes to level switch GY-VT) into pin #28. I checked multiple year diagrams around the 09 model and all used pin #39...Repinned wire to #39 and bam all lights for low brake level off on dash...cleared all codes, and vehicle is good to go....no clue what, how or who did the repin, but I'd like to smack em if I find them. either way problem solved.

This is interesting..I'm having a similar issue. Replaced bad ABS controller and it was programmed. So the ABS warning is off however I'm now getting brake fluid warning. I replaced the switch (even though I was sure it was fine). Wiring checks. I'm not exactly sure what is mean by 'repinned'. I apparently need to look at the used ABS module I picked up.

Re pinned means someone took pin out of connecter for something and should have put it back in correct slot but in his case the put it in the wrong spot

appreciate the info. I'm not exactly sure what that would look like but I'm going to yank the abs and take a look. I was going to clip the wire that come out of the abs to data line (wht/blu I think)but I was nervous about what that might do.