Hi,

I recently obtained an 01 ram van 1500 w 5.2l and 4 speed automatic.

So the computer is saying it's not getting a signal from the speed sensor, so I replaced it and nothing changed, still no speedo and red brake light and yellow abs lights plus check engine (speed sensor) are still on.

I read that the connector on the abs control module can let water in, but I checked it twice and its perfectly dry and no signs of water ingress at all.

Does anuone know where the wires for the speed sensor end up or are attached to? The ecu? What else could be wrong?

 

Which sensor did you replace? Normally, with those types of issues, its the rear wheel speed sensor on top of the differential that goes bad. Is that the one you changed??

 

No, it was the sensor on the transmission, I will replace the one on the differential next, thank you!

 

So i replaced the rear diff sensor and nothing changed, still no speedometer and all lights still on.

Previously rodents had eaten a bit of the harness but I thought I had it repaired. There could be a wire where it disappears at the gas tank that's chewed up. The gas gauge works.

Does the wiring for the rear sensor connect to the connector at the front crossmember area under the engine? If so, I want to run 2 wires to there and bypass the harness.

 

I think both wires come from, and go back to the PCM. Maybe from a splice on the power side. See if you can figure out which pins on the PCM the wires go to, and test continuity. See if the wires are indeed the problem.

 

I traced the wire colors (red and white/purple stripe) to the connector on the left hand side of the frame just behind the steering linkage. I got 2.6k ohms at the sensor, and infinite ohms at the connector. I grabbed an old extension cord from the junk pile (missing an end) and soldered it from the factory connector at the sensor, ran it under the running board, and soldered it to the connector at the front and it worked! I got speedo now. Reset the computer and lights seem to be gone. Somewhere the rodent got the wires for the speed sensor, but thankfully the other wires back there work.