ABS kicks in early, then disabled

[TimMitchell]

Hi all, long time Explorer owner (I'm on my fifth one), first time to this forum.

I'm having an issue with the ABS on my 2006 2WD V8 Explorer. When I first start it up, the first time I apply the brakes, the ABS kicks in and "pumps" the brakes for about 5 seconds. Immediately after that, the ABS and anti-slip warning lights show up in the instrument panel. This happens almost every time I start it. I've only had to brake hard a couple of times since this started, but on both occasions I noticed that the ABS did not kick in when I thought it might have.

In all of my Explorers, I've never had a problem with the ABS, and this one is strange in that it starts off engaging the ABS unnecessarily and then appears to disengage it entirely. Any tips on where I can start troubleshooting?

Thanks,
Tim

 

[Flag Gibby]

Pull the DTC's (diagnostic trouble codes) and it should point you in the correct direction as to the problem.

 

[TimMitchell]

Thanks. Can I do this myself, or must I take it to a dealership or service center?

 

[polizi212]

As Flag Gibby said you will need to pull the codes, If the lights on the ABS system are on its telling you there is a problem and the ABS will not work until its corrected. It very likely you have a wheel speed sensor that has gone bad.

 

[Flag Gibby]

Autozone has readers that will read the codes and they typically do it for free or I believe you can rent one from them.

 

[TimMitchell]

Autozone has readers that will read the codes and they typically do it for free or I believe you can rent one from them.

Thanks for the input. I stopped by AutoZone and they pulled the codes for me. The codes generated were:

B1676
P0562
P1000

The third one shows testing incomplete - I'm not sure what to make of that one. Code P0562 indicates a low system voltage, which is strange because I just replaced both my battery and my alternator in the last few days (I just finished the alternator tonight).

Code B1676, which appears to be most closely related to the issue at hand, indicates that the ABS unit is receiving less than 9 volts. Again, with a new alternator and battery, I have no clue why the ABS unit would be detecting insufficient voltage. Maybe the ABS unit itself is bad? Is there an easy way to troubleshoot that?

 

[polizi212]

The abs unit could be bad or it could have a bad ground or wire! Check all the connections and the wire harnesses that lead to and away from the ABS unit!

 

[Flag Gibby]

The third one shows testing incomplete - I'm not sure what to make of that one. Code P0562 indicates a low system voltage, which is strange because I just replaced both my battery and my alternator in the last few days (I just finished the alternator tonight).

Since you just worked on the charging system, go back and check all the connections and verify that the alternator is putting out the correct voltage before you do anything else. If the charging system is working correctly I believe that you should read 14.5V from the system when running.