I know this problem is very common and YES I HAVE SEARCHED.

About 2 weeks ago at 4 am I was on my way to the airport (1.5 hour drive) and right as I get onto the highway my VDC OFF light, SLIP light, and BRAKE lights all go on and my speedo drops to 0, on the highway. At the airport I did some searching and realized it is probably my brake fluid and brakes because I just got an inspection and was told my rear pads needed replacing soon.

However, when i got back to the airport from my trip and drove home there were no problems so i forgot about it. Then it happened again driving around town the other day so I picked up some brake fluid and topped it off (it was between min and max).

After filling up on brake fluid the VDC OFF and SLIP lights still come on, not the brake light and the speedo still drops to 0.

I have ordered new pads and rotors I plan to install next week once they arrive, but if that doesn't work what should I do, or am I being ridiculous and new pads and rotors won't fix this anyways.

I have been reading that the speed sensors on each wheel can go back or be loose, but I'm not sure where that would be or how to check it.

btw the car is a 2005 6mt sedan incase that matters to anyone.

Any assistance is helpful, I guess the goods news is that the car still seems to drive fine and since i recently installed my Kenwood DD i can get speed from the navigation.

Please help me out I just got this car a few months ago and really wasn't expecting any problems like this.

Thanks

 

I installed new rear rotors and pads today in hopes that the problem would go away.

It didn't.

Does anyone have any ideas?

I'm not so concerned with the slip and vdc off lights as i am as with the speedometer not working.

I will be calling infiniti USA and a dealer in regards to the TSB about this issue in hopes they can fix it. I have not yet been toa dealer as they are all far away so i am hoping they can provide assistance over the phone before i drive all the way there.

 

There is an issue with the cam position sensors, but that usually involves stalling along with the lights coming on. It could possibly be the makings of that. Did your check engine light ever come on? they might be able to hook it up and see if it tripped any codes.
GL!
rob.g

 

No I've never gotten any check engine lights and the engine runs totally fine.

I'm now thinking on of my wheel speed sensors is loose or faulty, or it could be a blown fuse as some have suggested.

I'll get under the car this week to check on the sensors (makes the most sense because of the speedo issue) and it seems like it being a loose connection would make sense since when I start driving it works fine, but once the code is tripped (ie the sensor gets loose) the speedo dies.

However the slip and vdc lights come on before the speedo dies most of the time (sometimes even before I have moved) so i'm not exactly sure.

 

hmm.. this happened to me once when I was doing donuts.. after the donuts I noticed it.. I turned off the car and turned it back on and it was gone and never came up again.. but then again I've only had the car for 3 days. lol

 

Did this problem occur shortly after installing the headunit?

 

So yesterday I called my local (1.5 hours away) dealership and basically explained the problem and said I wasn't looking to drive all the way there multiple times so was there any way I could check what the problem was before I had anyone fix it. They told me to have the code read somewhere (stating an AutoZone scanner probably wouldn't work because they use a proprietary system) and then to call them back.

So I took it to AutoZone and sure enough their scanner got the code P0500 (Vehicle Speed Sensor). At this point the service engine soon light had never come on during this entire problem

However, this morning on my way to work sure enough my SES pops up right as I pull into my parking lot and this time my scangauge II picked up the same code.

So does this mean one of my ABS speed sensors is shot, or loose or is it something much bigger and more expensive.

As usual, any guidance is appreciated.

I really do love this car and I'm kind of pissed this is happening after only owning it basically a month and a half (and only putting 2k miles on it).

The good news is that while my speedo doesn't work, the car isn't racking up miles haha, but in actuality I'd rather have my car work how its supposed to, including traction control and ABS given the amount of snow we just got in upstate NY.

Thanks guys

 

Here's what I've noticed on mine:
-BRAKE, SLIP, VDC lights come on when the brake fluid is low, came on once b/c my pads needed to get changed and once b/c the fluid was a touch low and it would trigger the lights in extremely cold weather
-I also had something weird happen summer of 09. I drove through a puddle and my speedo and tach went out, the car freaked out, started shifting erratically, etc. It would only do it when it was wet (happened twice), then it went away and hasn't surfaced in about a year and a half... Took it to the dealer, no codes, they had no idea. I'll chalk this up to a corroded connection or something else. It was entertaining to watch the dash lights turn on and off randomly (yes, the center console lights too), car also locked up in 5th on the hwy, which was kinda cool.

All in all, I have no idea what's up with yours, but when mine had the speedo go out, the tach would soon follow, and then the auto would start shifting hard and erratically. I established a connection between the speedo/speed sensor and the automatic. It needed to have an a speed input in order to set shift points. When the speedo went out, it was inevitable that the tach would follow, and the tranny soon after. I forget the name of the sensor on the automatic.

Since you have a 6MT, I am sure that a finicky speed sensor is going to mess up your shifting (duh), so consider yourself lucky in that regard. I drove my old manual car around for a week without a speed sensor, and it was fine.

Also, the odometer froze on mine until the "glitch" went away, so there are about 150 undocumented miles on my G.

 

Hmm, these kinds of problems are all too common on these cars that are supposed to be so reliable. You'd think Infiniti USA would find it unnaceptable for the SPEEDOMETER to stop working on the highway!

This isn't like a minor thing, it's a safety issue especially when it's interfering with the traction control and ABS systems.

I know this is all wishful thinking, but they should really be fixing this free of charge within warranty or not since it is a safety issue and kind of a big problem to have with cars that are supposed to be reliable.

Regardless of that, in reality I spoke with the dealer again this morning and the explained that possible problems could be a loose wheel bearing that is interfering with the ABS wheel speed sensor on one of the wheels and this could possibly be determined by getting the ABS system scanned for codes (he suggested I go to Autozone for this which I will do this afternoon).

So basically I'm hoping it's just a loose vehicle speed sensor since it always works until it doesn't (obviously), but if I restart the car before getting on the highway or a smooth road the lights dont come on and the speedo works just fine.

 

Yet another update:

Lights came on immediately after i went over a speed bump, signs point to a loose connection somewhere.

The good folks at Monroe Tire scanned the car today and said it was a P0500 code triggered by sensor A, but they didn't know which sensor that was and wanted 60 bucks to lift the car and look (I said no thanks and went home, I'll jack the car up this weekend and take a look underneath).

However sometimes the lights come over before I've even moved, so perhaps the connection comes in and out and sometimes when I start it it's out and others it's in, obvious I know.

 

This "problem" is not a big deal. These cars are very very reliable.

At least we don't have REAL problems, like higher mileage BMWs.

 

I do have to agree, these are great cars and much better than the alternatives.

However you do have to conceed that a month after you get a new (to me) car half the lights on the dash come on, and the speedo doesn't work.

Another update is that on my way down the hill from my house today the tach would drop to zero then catch back up to normal rpms (this happened after the VDC OFF and SLIP lights came on and the speedo had already dropped to zero). A quick restart and the tach was fine, the lights soon came on again and the speedo failed again though.

I read somewhere that water getting into the IPDM or whatever it's called can cause issues like everything i'm experiencing, but since it's 21 degress outside and i don't have a garage, any water is frozen and whats done is going to stay that way.

I will most likely take it to the stealership next week unless anyone has any brilliant and quick ideas to remedy the problem, or place to look for water.

 

I agree, I would be pissed off too.

You are describing many of the same symptoms that my car exhibited.

Is there any water leaking through the firewall? If you open the hood, and take a look at the side with the battery, you can remove the covers and access the rubber grommet that seals the firewall -> interior access point. I too assumed a sensor was loose or wet in, or connecting to, the BCM, but it stopped doing it, and I left it alone.

Maybe make sure all of the connections are secure where you can see them?

Where is the speed sensor on this car?

I found this thread, it's of no real use:
https://g35driver.com/forums/g35-cou...t-working.html

This one is a better read, maybe a lead?
https://g35driver.com/forums/g35-sed...nctioning.html

Another decent thread:
https://g35driver.com/forums/g35-sed...ats-wrong.html

Last one:
https://g35driver.com/forums/g35-cou...lfunction.html


Maybe go through these, and you'll have a checklist of potential problem areas to investigate before you go get raped at the stealership.

 

This thread is gold:
https://g35driver.com/forums/engine-...uctioning.html


It seems to outline the problem my car experienced.

Another question, where is the IPDM located?

The dealer****, in their infinite wisdom, replaced his gauge cluster, and the problem was still there. Then they wanted to charge him $2400 to replace the IPDM and the ABS Control Unit... crooks, and total idiots.




Here is a good quote form the thread:

 

Really weird I wasn't even looking this up it happend to me out of nowhere and went off in an hour I first went to the store and the BRAKE light came off when I started it back up then I stoped at the bank and when I got back in my car VDC OFF and SLIP turned off as well the only common thing I see between all those mentioned this is we have double dins/ head units maybe a relation? Either way its happining on models 03-06 and personally I think its liquid or the cold the day it happend it snowed about a foot and an earlier post mentioned a puddle ect...