ABS light (first time)

[Broke(n)]

When it rains, it pours. Today a new issue. I hope this isn't a sign of things to come with this truck.

Anyway. Today I went to Costco and as I'm leaving, when I started the truck, I noticed the ABS light was on. First time ever that I have noticed and I pay attention to my speed so always looking at cluster area. So I stop at the 7-11 really fast so the wife can run in and grab some things. I shut off truck (in case it matters, I leave headlights on as it is raining here today, FINALLY!) now when I start it back up, no more ABS light.

Just a fluke or does this happen with the ABS system when there is an error.
Seems it would stay on longer than just a start up, shut off, start up.
I assume I can test for error code even though it has shut off? I have an OBD scan and software (FORScan) that can read ABS.

Did a scan.

(WARN) [18:32:39.094] Checking COM3...
(OK) [18:32:39.492] Connection to adapter is established on COM3
(OK) [18:32:39.492] Adapter: ELM327 v1.5
(OK) [18:32:40.324] Connection to vehicle is established
(OK) [18:32:43.903] Vehicle: Ford Explorer V6 SOHC 4.0L 2004 MY, VIN: 1FM*********13311
(OK) [18:32:47.047] Found module: PCM - Powertrain Control Module
(OK) [18:32:54.016] Found module: OBDII - On Board Diagnostic II
(OK) [18:32:56.371] Found module: ABS - Anti-Lock Brake / Traction Control Module
(WARN) [18:32:56.561] DTCs in ABS: U1900-20, B2900-20
(OK) [18:32:58.506] Found module: IC - Instrument Cluster
(WARN) [18:32:59.009] DTCs in IC: B2659-20
(OK) [18:33:00.667] Found module: RCM - Restraint Control Module

 

[rocco123]

Check your wheel bearings

 

[gtyates]

I had a random abs light back last fall. Ran it by shop and it showed basically a network connection error. They reset it and everything was fine. They did mention that sometimes a weak battery can cause this, but battery checked ok. Long story short, the next day, while out of town, the battery went dead as a door nail. A quick trip to the local SAMs, new battery, and on my way.. They did check my charging system and everything was good. First time I have ever had that happen as a battery was dying. It has been about 9 months and no issues..

 

[Broke(n)]

Check your wheel bearings

A little more info, please. What am I checking for.

I had a random abs light back last fall. Ran it by shop and it showed basically a network connection error. They reset it and everything was fine. They did mention that sometimes a weak battery can cause this, but battery checked ok. Long story short, the next day, while out of town, the battery went dead as a door nail. A quick trip to the local SAMs, new battery, and on my way.. They did check my charging system and everything was good. First time I have ever had that happen as a battery was dying. It has been about 9 months and no issues..

Funny you mention battery. I have noticed my gauge showing voltage getting lower. It started out (when I bought the car) at about 1/4" past the half way mark. It is not at the half way mark. A look at my battery and positive terminal has corrosion.

 

[Aceallways]

Mine came on more and more frequently until it finally stayed on.

Never did anything though.

 

[rocco123]

To check wheeL bearings, lift wheels off ground. U can do fronts then rears. Grab the wheel at 12 and 6 o'clock positions. Then pull the 12 oclock, then 6 oclock next, check 3 and 9 positions. If you feel play then most likely u have a bad bearing. Do this for all wheel assemblies. Very common on 3rd generation express to wear out.

 

[Broke(n)]

Does this cause ABS issues?

 

[Exproblems]

Does this cause ABS issues?

Yes, a bad wheel bearing can cause ABS warning lights to go off. So can electrical issues (break or corrosion) within the ABS wiring or a bad ABS sensor itself. I've got an ABS issue going on with my Explorer as well. I had the ABS warning code read at an Advance Auto Parts store and mine came back with a "C1155 code" for a "left front (driver side) bearing sensor fault". I've checked the wheel for a bad bearing just like "Rocco123" told you to do and I get a "slight" left to right movement, but no movement top to bottom. I hear no bad bearing noise and my tires are wearing down good and evenly like they should. I can't really tell if the slight left to right movement I get is from the steering (tie rods) giving a little with the weight of the vehicle off of the ground? I also visually looked at the ABS wire and traced it back to under the Master Cylinder where it joins another wire bundle and it looks good and intact from what I can see without pulling off the brake caliper at that end of the wire. I plan on removing the brake caliper and bracket later this week when if cools off outside and check it there. I did change my front rotors and brake pads last August 2014 and I am wondering if I may have some how pinched the ABS wire behind the caliper mounting bracket since my issue started in Dec 2014 just 4 months later.
FYI, My problem started on Dec, 10th, 2014 when I hit a small bump on the Thruway doing 65 mph. Thru winter the ABS light would go off once in a while just after hitting a bump in the road, but now since it has finally warmed up considerably, upper 80's here, it goes off quite a bit more frequently, daily and multiple times a day. Now it even goes off when I start up the engine. It also causes my ABS brakes to kick in and out when I go to stop for a red light once in a while. The parts store clerk says my problem is most likely "electrical" since the bump in the road sets off the ABS warning. He said it doesn't sound like I have a bad hub bearing issue. Good luck getting yours sorted out!

Update: I removed the driver side, front brake caliper bracket today, Monday 5-11-15. I then inspected the ABS wire right up to where it connects into the top/back of the driver side, front wheel hub bearing assembly. I found nothing visually wrong with the wire. I then got balls'y (big mistake) and removed the retaining screw to the ABS sensor from the bearing assembly housing. After soaking the screw with some PB Blaster I then took a small Allen wrench and removed the screw holding the sensor plug and wire in place. The sensor would not pull off like I hoped it would. The rubber bottom of the sensor was fused by rust to the wheel hub and had to be gently pried away from the hub. A tiny portion of the bottom rubber material (opposite end from the contact surface) broke off the sensor plug bottom, but the metal contact surface of the sensor connector was okay. I then cleaned up the sensor connector surface and the contact surface on the bearing assembly with some emery cloth and reconnected the sensor to the bearing assembly. No problems there until I started the vehicle up and now the ABS warning sensor goes off immediately after starting the engine. Prior to this the ABS warning would go off when I hit a bump in the road and occasionally on engine start up. I did not disconnect the negative battery terminal prior to working on it, but did so when I went to inspect the other front ABS wire on the other side of the vehicle. Same result after reconnecting the negative battery terminal, ABS warning went off right away after starting the vehicle. I wouldn't recommend doing what I did here, even though it probably didn't change much in the type of repair I need done here. (Note: this was my first time removing an ABS sensor from a hub) I'm not sure if just the sensor/plug harness can be changed by itself or you need to buy the whole wheel hub bearing assembly with new sensor attached as one unit?

 

[Broke(n)]

Bumping this since I added it to another thread that was a different topic.
I'm no pro but after reading around, it seems like some reprogramming is in order?
I got these scan results today using my laptop and FORScan

===ABS DTC U1900-20===
Code: U1900 - CAN Communication Bus Fault - Receive Error

Status:
- Previously Set DTC - Not Present at Time of Request
- Malfunction Indicator Lamp is Off for this DTC

Module: Anti-Lock Brake / Traction Control Module

Diagnostic Trouble Code details

CAN Communication Bus Fault - Receive Error

Note:

DTCs that start with 'U' are faults which occur during module-to-module communication.

Modules should never be replaced based only on a 'U' code. These codes do not always indicate a problem, and can be caused by normal diagnostic functions, carried out on the vehicle.

===END ABS DTC U1900-20===

===ABS DTC B2900-20===
Code: B2900 - VIN Mismatch

Status:
- Previously Set DTC - Not Present at Time of Request
- Malfunction Indicator Lamp is Off for this DTC

Module: Anti-Lock Brake / Traction Control Module

===END ABS DTC B2900-20===

 

[Bushdrift]

Hi how'd you go with the b2900 vin mismatch? Plz any help would be greatly appreciated as I'm stuck with it and p1000