A/T code 2

[CGB]

Hi Guys, I need your help.

This problem is with my 92Q, now with 199000 miles. Last week my speedometer stop working, along with no power steering assist. I run the self diag test and came up with code 2, which points to the speed sensor.I figured, great! I know what the problem is. Mind you that I can not get under my car at this time. So, I looked through the FSM and on page EL 151 it shows the speed sensor location (on rear extension)What that means? Where is it? Is it easy to get to?

I would like to take it out and test it ( by FSM guidelines ) to make sure that is the problem. Joe's price for the part is about $135.

I hope that somebody run into this problem before and let me know how difficult will be to remove/replace this part.I'm getting too old to do any "heavy whrenching". I hope that this could be an easy replacement part.

Thanks in advance for your input!

CGB

[Q451990]

From what I understand, it's a pretty easy fix. That said, I just spent about 30 minutes looking through the FSM, and can't find a location either! The rear extension is the tailpeice that comes off of the back of the transmission.

I think if I was in your situation I'd call Joe at Infiniti of Scottsdale (1-888-216-5328) and see if he can email you a part diagram with the part highlighted. The other option is to test the sensor at the Transmission Control Unit Harness per the FSM - to make sure it's bad. If it's no good, order the part - and then look for it's twin under the car.

Heath

[elwesso]

You mean this???

[Q451990]

I don't think so... My understanding is that there are three sensors:

- "Turbine Revolution Sensor" which is that one that's a real bear to get to. It's on the top side and requires transmission removal, stretching the motor mounts to the edge of their resistance, or cutting a hole in the floorboard.

- "Revolution Sensor" that monitors the output speed at the rear of the transmission.

and the "Speed Sensor" that CGB is looking for. Maybe the revolution sensor and speed sensor is the same - and they just called it two different things in the FSM?

Apparently the ECU/TCU monitor the input speed to the transmission, and output speed to the driveshaft to see how much slip occurs in the transmission.

Heath

[elwesso]

they have diagnostic procedures for them just doesnt tell where they are.....

I remember Rob changing something out on the transmission when he had his 4.08 in there to change the speedo reading.

[CGB]

Thank you guys for your input.

Heath is actually right. There are two sensors: revolution sensor and vehicle speed sensor, which is the one that gave me the code 2.There's a picture of the sensor in the FSM, EL56.

Anyways, I've scheduled an oil change for tomorrow, at the dealer.So we'll look to see where this sensor is.I'll update with the findings.

Thanks again!

CGB

[Q451990]

If you can take a picture to post that would be great... I'll print it and put it in my growing folder of "stuff I'll need someday"

Heath

[CGB]

Ok, went to the dealer today and unfortunaly they didn't have the sensor in stock but it has been ordered. Since I know the Serv. Mgr. he'll give me the part as the same price as Joe's. So I'm going to have them replaced it.

The sensor is located in the right hand side of the transmission's tail and is held by one bolt. The harness wraps to the top of the transmission and connects on the left side, where all the connectors are.It looks like an easy replacement. I think that book calls for 1/2 labor.

Here's a picture of the sensor's location.

CGB

[elwesso]

THanks for posting!!!

I actually got a code 2 on my transmission diagnostics (have been getting an intermittant TRANS MALFUCTION) but my speedo isnt doing anything weird......

Good information!

[goody90q45]

This is also a very good picture showing the exhaust hangers attached to the rear end of the transmission mount. Maybe one of our moderators can transfer this pic to the current thread discussing installing the (poly) transmission mount and exhaust hangers.

[CGB]

Hummm.... Interesting. In my opinion, the code 2 have to have something to do with the Transmission Malfunction code, because as soon as I found the code 2, I'm getting the same message, off and on.

Mind you that I have my 92 since 1995 and I've never seeing this code (TransMalfunc) and my transmission works fine and it has been properly serviced.

What do you think?

CGB

[elwesso]

This is also a very good picture showing the exhaust hangers attached to the rear end of the transmission mount. Maybe one of our moderators can transfer this pic to the current thread discussing installing the (poly) transmission mount and exhaust hangers.

Guess that would be me, eh????

Im on it.

[elwesso]

Hummm.... Interesting. In my opinion, the code 2 have to have something to do with the Transmission Malfunction code, because as soon as I found the code 2, I'm getting the same message, off and on.

Mind you that I have my 92 since 1995 and I've never seeing this code (TransMalfunc) and my transmission works fine and it has been properly serviced.

What do you think?

CGB

Im still looking into it.. Whenever I start my car after its been sitting for a few days and its cold, i get a hicas light too but it goes away as soon as I start it... Possibly because i was slightly low on PS fluid, but only noticed it today..... :

So far its not really been messing anything up if you let it warm up, so im not going to worry about it right now.... but im keeping a close eye, and have my phone with me at all times with Joes number in it.....

[Q45tech]

As food for thought the transmission tcu looks at 3 rotating sensors plus tps voltage:engine rpm [via CAS][input to tc], ............turbine sensor [output of tc] and tail shaft- driveshaft rpm the so called speed sensor [which has a gear reduction to match diff gear and tire loaded radius to derive an approximation of forward speed and miles driven.

[elwesso]

so the speed sensor in the rear of the transmission (as noted) is really the only one that is important to the speedo.....?? Shift points are more controlled by the TCU and so on.....

[chinaonnitrous]

Guess that would be me, eh????

Im on it.