hahaha

i had a p0500 code and i replaced the VSS sensor.

i have a code reader (scan gauge 2, good stuff, by the way) that also reads some of the stuff the ECU monitors (intake temp, water temp, and so on). after i replaced the VSS sensor, i plugged the reader in, cleared the code and took a short drive. for the first minute, everything works, then i noticed the "mph" is "0", meaning the ECU is not getting data from VSS (my guess).

according to the code reader, my ECU is not getting any "speed" data because the "mph" is showing "0". the odd thing is, my speedometer still works. i don't understand how this is happening. any idea?

the test drive is short, so it didn't trigger the p0500 code, but i'm sure if i drive it long enough, the p0500 code will come on again. anyone has any idea what i'm dealing with here?

thanks.

Nopike

iTrader: (2)

The VSS signal first goes to the speedometer and from there to the ECU If your speedometer is working fine then the VSS and that portion of the circuit is fine. It's possible the VSS signal that leaves the gauge cluster at pin 24 (pink with blue stripe wire) is not getting to the ECU pin29 (still pink/blue wire).

You should check the connection of the Pink/blue wire at the back of the gauges and the ECU.

How did this problem start? Just out of the blue? Were you doing something????????

Your cruise control also uses the same VSS signal from the gauges so you could see if that works, although that will probably not tell us a whole lot.

hahaha

hmm... interesting.

the problem first started a couple months back. i had a p0500 code, so i looked up the code, picked up a VSS from O'Reiley, installed it, cleared the code, and all was fine. BUT i realized my speedometer reading was off, it read too low. i made a guess that they gave me the VSS for automatic transmission (mine is a 5spd), sure enough, they checked their computer and they gave me the wrong VSS. so they ordered the correct VSS for me and i installed it. the first couple weeks after this 2nd install, all was fine, but lately it triggered p0500 again, so i thought maybe it was a defective VSS, so i brought it back and exchanged for another VSS (5spd). this time, i installed it, cleared the code, and drove it for a block while monitored some readings off my scan gauge thingy. i noticed the "mph" worked the first minute, literally for about the first minute or so, then stopped working; it read "0", so i knew somewhere down the line something is not working right.

i did not realize the VSS signal goes to speedometer first then the ECU. i'm curious to see if messing with the speedometer would fix the problem. it's really odd though, because if it was the speedometer's problem in the first place, then why didn't it throw any codes after my first and second VSS install? assuming it is indeed my speedometer that's acting up, does it mean my VSS and speedometer both failed within a couple months of one another? how unlikely is that?

i haven't tried the cruise control since my 3rd VSS install. however, with my 2nd install (the correct VSS that worked for a couple weeks), it would work until the p0500 showed up. i know because i tried to clear the code and run the car a few times, and there were a couple times when the cruise control worked fine and then the green cruise light started blinking and the cruise stopped working at the same time.

i've never removed or uninstalled the maxima's gaguge cluster. i'll look up instructions on this forum. hopefully it's not too hard. meanwhile, anyone else has any ideas as to what might have been causing the problem, feel free to share.

thanks.

-Chung

ATTappman

If your speedometer is working normally, and you're still getting a P0500, then the problem is in the path between the combination meter connector on the back of the cluster and the PCM. Assuming you don't have a broken or corroded wire between the cluster and the PCM (unlikely IMO) you can either replace the whole cluster with a used one, or you can replace the speedo head and/or the flexible circuit board on the back of the cluster. After I replaced the flexible circuit board it stopped throwing the code.

Removing the cluster is not hard, but you have to be careful not to break the cluster bezel.

Nopike

iTrader: (2)

My guess is that your VSS was always fine, because if it was broken and you installed a new one your problem would have been solved. If your speedometer always worked (except when the reading was inaccurate) than your VSS was always fine. I would reseat all of the comnnectors on the back of the cluster especially the flexible connector and the connector that has the Pink/blue wire running to it.

Why didn't it throw any codes after your first and second VSS install? You probably have a bad connection and an intermittent problem between the cluster and the ECU. It seems to happen all the time on the org, someone changes something, the problem appears to go away and is fixed, and then it comes back. If you still have your original VSS and install it the problem may once again go away.

Nopike

iTrader: (2)

Th FSM suggests checking continuity between pin 24 (pink with blue stripe wire) of the cluster to ECU pin 29 (still pink/blue wire). If you have an ohmmeter, with everything connected and the car off you should read a short, 0 ohms. It also said to check for a short to ground. This means you should not have 0 ohms from ground to the pink/blue wire.

hahaha

wow, thanks for the replies. don't you just love it when you post your problem on a forum and people just poured out their knowledge and experience and help you solve something? no BS, no nonsense. good stuff.

i drive my second car a lot more often now, so fixing this VSS problem isn't really a priority. but when i get a chance to take a good look at it again, i'll follow you guys suggestions and see if it gets fixed.

thanks, you guys, i appreciate your inputs.