Vehicle is a 1996 Aero* XLT, 4.0 engine with 155000+ miles. I'm getting the P0500 code with the OD light blinking. Tranny is not shifting properly. Did not look at the speedo or check the cruise due to worry about making it to my driveway. I have had ocasion to set the cruise to 45MPH and at times it will drop out. I don't know the lower limit on the cruise. Is this speed sensor the same as the VSS I have seen mentioned in searching the forums? Would like to find out its location. Pls send PM or post here. Thanks.

 

Yes, the VSS is the Vehicle Speed Sensor. In your car, it's in the rear differential. You can pull it out and check its resistance with an Ohmmeter. I don't know the proper resistance, but it should not be a dead short or totally open.

 

Odd!!! I just went to Autozone site to see what it looks like and they say it's on the tranny. I have known them to be wrong before though. I will check to see what NAPA and others say. Thanks.

 

NAPA lists a differental speed sensor, an A/Trans speed sensor and a vehicle speed sensor. No indication of which is the sensor A.

 

with the EEC-V advanced PCM powertrain control units Ford brought out in the mid 90s such as the 96 Aero, they went to the rear diff. speed sensor to support the PCM, cruise control, advanced RABSII and other powertrain features.
could be failed sensor, it's wiring or connector.

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If your Aero is 2WD, the only speed sensor is on the diff. It's a common failure item on all Fords of that era.

If you have AWD, I believe there are two more speed sensors on the transfer case.

 

the 2 speed sensors in the AWD transfer case are only involved in the circuit for the AWD electronic control algorithm.
not used for PCM air/fuel engine power, speedo or cruise control functions


sometimes the failure with these rear diff speedo/ABS sensors is the tone ring mounted on the ring gear. breaks or teeth fall off.

 

Thanks for the replies. 96_4WDR keep me strait here. It is 2WD. Per fordparts.com, they show DY-1227 and DY-588 as sensors. Is there a separate ABS sensor for my vehicle. I ask because my ABS light is on intermittently. Also this shifting problem is intermittent. I would think that would eliminate a tone ring problem. I just want to make sure I get the correct part #. Thanks.

 

This is a late Aero 3.73 Trac-Lok diff I have in storage. Not sure what year (obviously 1990-on, though). I just laid down and looked under my '97, and they look the same.

Click HERE for larger


Ford calls the DY-1227:
Auto Trans Speed Sensor, 5R44E/5R55E - 5 Speed Auto Trans ; Sensor - Turbine Shaft Speed

However, lots of places do call that part a VSS. Images for the trans speed sensor seem to have a pigtail attached, though.

The DY-588 looks like the gear-driven one in the rear of the trans on the earlier Aeros with digital dash, like my '89.

[later]
I have to say, I still can't answer your question. The info I'm seeing from various places is contradictory. The NAPA ATP 16501 looks like the one I'm thinking of in the diff, and they do call out it being installed in the diff on NAPA's site.

 

If your brake warning light is coming on and off, I would also check the level of the brake fluid if you haven't already, and maybe the shuttle valve switch in the front of the master cylinder. It tends to build up corrosion and cause intermittent shorts, and once the brake system starts acting up, it will disable other things such as ABS, cruise control, the lockup in the torque converter, and the 4wd if you have that.