Nissan Repair: gauges, nissan sentra, speed sensors

Question
Pertaining to the wiring harness that you mention--- is that under the car near the transmission, or the harness behind the cluster or both? Also, you said that "Nissan mentions about a short in the harness"---where can i find that information to read the whole article and what, if anything are they doing about it? Recall or what?    thanks again for your help
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Followup To

Question -
I bought a used 2000 nissan sentra.Two weeks later while driving, the gauges started going crazy (jumping up and down,sticking in one place, etc.). Then the check engine light came on. I had the codes read and it was PO5OO (speed sensor). I also took out the cluster and cleaned them as you suggested with the eraser and tuner cleaner. Cleared the codes and two weeks later they were back, this time it read PO5OO and P0460. I also learned that the previous owner had the speed sensor changed (not at nissan dealer). Could it be that the sensor was not put in correctly and/or defective?  How many speed sensors are there and is it difficult to do myself?  Also, how can I check to see if the recalls were performed on my vehicle before I bought it, especially the one about the wheels cracking? Any help would be greatly appreciated.

Answer -
As far as recalls performed, you'll need to get that from the dealer. Since they get paid from the manufacturer for doing the repairs, they will be happy to assist you. There are two speed sensors. The output speed sensor handles the speedometer. This will be located to the rear of the transmission and is gear driven. The input speed sensor will be located towards the front of the transmission. As I was reading about this, Nissan mentions about a short in the harness, which turns into a nightmare if this is the problem. P0460 is the fuel sensor, another gem to repair. It's located on the fuel pump in the gas tank. Both sensors send information to the PCM. Now it gets tricky, since both sensors report to the PCM and you mentioned all your gauges going haywire, I am leaning toward a bad PCM. Check all your fuses, under the dash and under the hood. Inspect the wiring harness for melted or crushed wires.


Answer
I would check any and all I could find. When you see this kind of TSB they try to down play it so everyone won't get too excited. CAREFULLY check the plug into the PCM. Wow, looking for the other thing I found a TSB saying that the speed sensor issue is due to low voltage cause by a faulty alternator or battery. Just another thing for us to check. Make sure your alternator is charging at over 14 volts and your battery is holding a charge. See, this stuff stinks.