I know this is the wrong forum, but for whatever reason I can't post in the other (DIY) so...
2001 1500 4x4, 5.2 Manual 68k mi.
Here's the deal. Check engine light was on, code said bad PCM (601). Replaced PCM, engine light goes off. About a half mile into test drive, ABS light and Brake Lights come on. They'll clear when I kill the engine, but will come back on within a mile. What do I need to do now?!?

 

Read codes again.

 

Umm, you replaced the pcm because the ABS and Brake lites are on?

 

No, originally the check engine was on, and the code said bad PCM.
Replaced it, and after that the ABS and BRAKE light came on.
Local mechanic said it was probably either a bad rebuilt PCM.
Also said it might be a code that the bad PCM couldn't/ wouldn't produce.

Anyway, got a new PCM inbound, and will probably start with the speed sensor after that...

 

After replacing the sensor on top of the rear diff, and making sure you don't have a pin hole in the brake line running to rear next to the gas tank and checking wheel cylinders. If you still have the lights(abs and brake), you may need to have the pcm flashed by the dealer.