ABS, emergency brake, speedometer and stalling

Hi there,

I recently bought this truck and when j did I had it looked over by a mechanic and he told me that the problems (in the next paragraph) would be solved if I just replaced the ABS sensor. I did that and it has not fixed the problem. He also looked at it and cleaned out the rear end today (something about magnetism affecting the sensor) but that did not work. I guess I have lost faith in him, and also money! So now I would like to try something else. After researching as much as possible I am wondering if replacing the abs module would fix the issues and wanted to get your opinion.

Problems are :
Speedometer does not move at all.
ABS light is on.
Parking brake light is always on.
Check engine light is always on.
Truck stalls under braking (but not engine braking).

As far as I can tell the engine runs just fine, and manual transmission works fine.

Thank you for your help, I really appreciate it.

James :-)