Speedometer issue(yes I checked all the usual issues)

[schaffer]

I have a 98 ranger. 4wd,5 speed,4.0 etc.

My speedo does not work. I changed the sensor. Checked all the fuses it could be. Checked the wires for a short.


I'm stumped. What could it be!

 

[mp3deviant721]

Bad cluster?

And you are posting in the wrong forum. There's a sub-forum all the way at the bottom for speedometer questions.

 

[schaffer]

All my other gauges work except for my speedo and odometer.


Their has to be something im missing.

 

[shane96ranger]

I assume by "replaced the sensor", you mean the ABS speed sensor in the differential. Even though it's new, I would still run an ohm meter across it and see if it's good. It should read between 0.8 and 1.4k ohm. On 98's, I believe they also run through the GEM, so keep that in mind.

EDIT: Here's a picture of the circuit

 

[holyford86]

probably wouldn't be a bad idea to do some gauge sweeps if you have access to a scan tool that does it

 

[schaffer]

Replaced the one on the rear diff. Checked all the wiring from it. Still had the factory loom on it. Check where it came out infront of the gas tank,through the floor and into the kick panel.

Is it possible I got a faulty sensor from the auto parts store? Can I buy a
Cheap GEM(i.e not at the dealer). I noticed that the door ajar indicator looks to be tied into the GEM. My ajar indicator has been stuck on,could have something to do with it?



Am I missing any fuses that I wouldn't think of? I looked at the number 26 fuse and it looked good. Could It be any of the fuses or relays under the hood?

 

[schaffer]

My speedo is dead, btw. No fluctuation at all. It worked for a while when I got the truck then went out. Came back on very briefly two times but now I'm not getting anything.

 

[85_Ranger4x4]

As far as I can tell there was a senser in the rear diff for the ABS but there was still a cable going to the transmission/t-case. AFAIK the Ranger never went away from a cable drive speedo.

 

[schaffer]

It was my understanding that the 98-00 had the speed from the rear abs unit as a raw signal and sent it to the PCM.the PCM juggles the signal around and spits out the speed.

 

[Earl43P]

In your case (4wd), the raw VSS signal is processed by the 4WABS module, then routed to the PCM, GEM, Cruise and Cluster.

You'll want to ring continuity on the two wires from the VSS to the 4WABS Module. The wire colors should be LG/BK (light green with black stripe) and RD/PK, going to pins 22 and 21 at the 4WABS module.

You could also set your VOM on millivolts or ohms, connect meter leads to pins 21/22 and spin the rear axle and see if the readings pulse as the VSS reads the teeth on the tone ring.

If no pulses, it may be time to open the rear axle cover and examine the tone ring.

The diagram posted earlier applies to RABS, not your 4WABS. If you want the schematic (from the 2000 EVTM), simply send me a PM with your e-mail address.

Under Hood JB fuse #3, 7 and cab fuses # 9, 11, 14, 26 need checked.

If you haven't opened up the big square connector under the driver seat, they tend to corrode. Might clean that up and apply dielectric grease.

 

[85_Ranger4x4]

It was my understanding that the 98-00 had the speed from the rear abs unit as a raw signal and sent it to the PCM.the PCM juggles the signal around and spits out the speed.

Alrighty, in typical Ford fashion they couldn't make up their mind on what they wanted to do.

http://www.therangerstation.com/tech_library/speedometer.htm

 

[schaffer]

I Checked all those fuses as well as the connectors under the seat. Even took a good look at connectors under the truck.


Really hoping it isn't something in my rear.