RX1Cobra

Today on my way to work my dash light up with saying check brake, stability system etc. This happened once before about 4 months ago and it was the ABS fuse. I replace the fuse and all was fine until today. I haven't checked yet but I assume it's the fuse again.

This only happens in heavy rain so I'm thinking a plug or wire is letting water in somewhere. I would think most common would be a wheel speed sensor but would that blow the ABS fuse? I have Forscan so I can pull codes but last time it happened I couldn't find anything with the code (C0020).

Truck is a 2015 3.5 Ecoboost supercab XLT 302A. It has 51K miles so I assume this wouldn't be part of the powertrain warranty? I'm good with cars so I hope I can track down the issue would just like a place to start.

Also, and maybe unrelated, I remote started the car two days again and when I got out it stayed running. Gauges and everything turned off but the engine was on. I had to get back in and turn it on and off again for it shutdown. Thought it was a random fluke cause it never did that before.

RX1Cobra

And to add when it appeared today it cleared itself and went back to normal. Two minutes later it came back and stayed on.

Gordy49913

I'd have a hard time believing the sensor would blow the fuse. More than likely the ABS module would shut off the sensor or disable itself and give you the message. According to the wiring book, 3 fuses feed the ABS module. F61-30amp, F11-60amp and F107-10amp. It looks like the F61 controls the brake valve, the F11 not sure and the F107 powers the electronics module itself.

C0020:16 ABS Pump Motor Control:
Circuit Voltage Below Threshold
GO to Pinpoint Test G

C0020:17 ABS Pump Motor Control:
Circuit Voltage Above Threshold
GO to Pinpoint Test G
The error maybe due to the fuse being blown the first time. I have to ask, was the fuse actually blown, or did you swap it and it started working again.
I would look for errors again. Clear the errors and see if it comes right back as long as the system is failing.

C0020:49 ABS Pump Motor Control:
Internal Electronic Failure

RX1Cobra

Fuse was 100% blown, it was very visible. I took it and put it back in the first time and nothing. Went and got a new one and good again until today. Odd thing is that when I took a quick glance at the fuses today none appear to be blown. This was just a quick check because I'm at work and it's raining.

I have a cheaper Bluetooth adapter I was using with Forscan. It just said C0020 with nothing after it. May need a better one so that I can see the more detailed code?

Also, it stayed running on me again. Had to do a second key cycle for it to turn off (remote start not used this time). Not sure if these are connected or a coincidence?

Gordy49913

The fact that it started working again is a sign the fuse was fine. One of the things mentioned for troubleshooting was to check your battery connections making sure they are tight and clean and also the plug on the ABS module for corrosion.
Wonder if this could be a battery issue, is it the original battery still? Read plenty of times here people having strange issues with the truck and when the battery is tested it is bad. Can't say what could cause both of the things being bad at the same time and related.
If you are seeing all the modules with it the cheap adapter, it will be fine and give you all the errors.

Napalm

SO wait a moment - the ABS failure while driving has only happened once - and it do so in the rain? OR does it happen fairly often and when it happens it's when raining.

There are a handful - and I mean few - people showing they have some water leakage in the windshield such as to allow water in behind the IP. This can run down harnesses and into the back of electronics and might cause some shorting.

So that could be a bigger issue - and you only see the problem with one system currently.

Now that said, popping a fuse is always a cause for concern with a computerized car. Do you have any other odd issues or is it confined to the stability control system (ABS, Traction control, stability assistance, trailer sway)?

Do you find the floor wet under the interior fuse panel?

RX1Cobra

The firs time (back in Feb) it didn't start working again until I put a new fuse in. 100% sure that time the fuse popped. After I changed it was good again until today. This time it doesn't look like it so hopefully I can pull a code. When I get home today I'll check the fuses again to be sure but they appeared to be OK.

I planned to check the battery and all connectors related to the ABS. Really hope that a code points me in a general direction though.

It is the original battery and the thought did cross my mind but it starts and runs fine. I guess I could change it and see.

It has happened twice. First time (in Feb) I found the fuse blown and replaced it. I knew it was strange but it was between -20 and -30 for days when it happened. Chalked it up to weird things in the cold. And it happened right when I started the truck in the driveway.

Today, the second time, it happened while driving. Everything popped up and 2 seconds later cleared itself. 30 seconds later it was back and stayed back. I haven't noticed the carpet being wet but I'll for sure check it. At least once a week in the winter I go through a carwash and it's never happened there.

The only other odd issue, that just started on Saturday, is the car not turning off with the key. More info here...

https://www.f150forum.com/f118/truck...emoved-445676/

RX1Cobra

So it has 3 DTCs for ABS.
c0020:49 internal electric failure - Per forscan light is on because of this code
U0151 - Lost communication - light not on for this
C0051:62 - steering wheel position sensor signal compare failure - light not on for this

Also got a check engine light now
P025A Fuel pump control module control circuit open - light is on for this (new since post)

I do also have a code for low battery voltage -
U3003 - battery voltage - light not on for this DTC

Can the battery really be giving me all these issues???!!!

RX1Cobra

I cleared all the codes and C0020:49 always comes back. All others don't and every other module shows no faults. I checked the plug at the pump and its good, no bent pins or any corrosion at all. Wiring looks good, didn't break open the loom but so no reason for concern anywhere. All 3 fuses are good for the ABS. Swapped with others and no changes.

It fails the selftest in Forscan. Looking like the control module failed. Could explain it blowing the fuse before? And now just totally went out. Battery cables clean and tight and resetting the system seems to have fixed the car not turning off.

So should I go further or just replace the module? And can I do just the module itself instead of the entire pump? Would this be under powertrain warranty (51K miles)?

And thanks for all the help so far everyone. I appreciate it.

Napalm

Yes a low battery voltage can cause many module issues. Some are totally unrelated which will cause a tech fits. Before replacing a module - though the blown fuse has me worried.

Get another good battery or a vehicle with a good battery - jumpered together. Or straight up replace yours - either way.

And check with a meter that at the vehicle battery cables you see a clear 12._ VDC. somewhere over 12.2 up towards 13 is fine. This way you have plenty of voltage support for the systems - then start the car or turn the key. If you find you get no codes after that - then clearly your battery is dropping voltages during start up and undervolting modules.

All the modules expect a input voltage range. Usually it's in the 9-14 realm. Give or take a bit. If something like the ABS controller saw 6 V on start up - it's start check would fail and any number of faults could return.


Now another issue - internal voltage regulator - might have ate a bullet too - so the module could be dead. But I like to exhaust options before doing something as big as that. OH and do you have warranty?