Hi, I have a 2000 ranger 3.0 auto 4wd xlt. I bought the truck cheap with a problem thinking I could fix it and have a decent little truck. Needless to say I’m getting my teeth kicked in and I’m getting nowhere.

So the truck is logging a p500 code, Speedo is inop and after truck makes a violent 1-2 shift @3500 rpm the O/D light starts flashing. With that being said I have monitored and test drove the truck abs module reads center axle sensor and both front sensors, the gem module reads 0 mph and pcm is 0 mph as well. I have no abs light on. I have checked wiring from sensor to bulkhead connector under driver seat. Ohms and load tests good. From underfloor connector the abs signal wire appears to run to the abs module under the the hood (red wire pink stripe ) and from abs module to bottom connector of gem module pin 9 (gray wire black stripe) all wiring seems to check good. I have installed another used abs module and gem module. ( gem module and abs module wasn’t the correct part number but just a test )

Any suggestions or tips ? Anybody have a pin out or can tell me how the rear axle speed sensor is wired to the gem ?

 

Welcome to the forum

The Rear axle ABS sensor is a VR sensor so generates its own AC Voltage, but the voltage is not used, the AC Sine Wave is, that's the speed signal for ABS, only the "+" half of the Sine wave is used so one wire on the ABS sensor will show as a ground
Both wires run to ABS Module

In 1998-2000 Rangers the rear ABS sensor was also used as the speed signal for speedo/odo, computer, and cruise
Then rear ABS outputs about 20,000ppm(pulses per mile) and the Ford speedo, computer and cruise only "understand" an 8,000ppm signal

So Ford added a signal converter to the GEM module(body computer) but just in the 1998-2000 GEMs
20,000PPM in, 8,000PPM out
Anyway thats whats happening

Since your ABS light is not on, the ABS is getting the rear axle sensor's signal
P0500 means the computer is not getting the 8,000PPM signal from GEM, neither is speedo/odo or cruise

GEM wiring below, pin 9 should be the red/pink wire spliced to the red/pink wire that runs from rear ABS sensor to the ABS module

GEM Pin 1 is the grey/black wire that runs to cluster(pin 1), computer(pin 58) and cruise(pin 3) with the 8,000ppm signal

Do you have Rear ABS or 4 wheel ABS?
I can post wiring for those, just need to know which one you have