Last week my ABS light, brake light and engine light came on. Along with this my truck will sometimes stall when I come to a stop. I am getting the P500 code. I chacked all the connections and replaced the rear diff sensor. Did not fix. I found another thread that said to test the module I can check the ohms between the red/violet & white violet wires on the ABS harness. Checked those and am getting 1960 ohms (within range) thus this particular thread said if ohms are within range than module is bad. So this is when I stumbled across myairbags.com. Does anybody have any experience with these guys as far as addressing this issue and does what I did to check module seem correct?

 

http://www.obd-codes.com/p0500

most likely you have a bad ABS/Speed Sensor. Even if resistance is good sensor can still be bad.

Replace sensor, if you still have the issue then the module is likely bad, or there is a bad wire somewhere.

 

I replaced the sensor in the rear diff. I know that there is another one in the transmission but I have not replaced that one yet because from what I have read that it most likely is not that sensor. I also forgot to mention that my speedo does not work anymore. Everything else (cruise, blower, lamps, ect...) seem to work fine. I also removed the fuse box from underneath the hood and checked for corrosion in the plug and it was clean. Same with the plug on the ABS module.
In regards to the sensor in the trans, has anyone replaced that sensor and had it fix this issue. From what I am gathering this is a pretty common (strange) issue.
Thanks for any and all input