How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Greg Your Own Question
Greg
Greg, Technician
Category: Car
Satisfied Customers: 7057
Experience:  Automotive diagnostic tech
29331485
Type Your Car Question Here...
Greg is online now

I saw a post on Just answer and the guy described the exact

Customer Question

I saw a post on Just answer and the guy described the exact symptoms of my car. His problem was solved when he replaced the "gearbox attenuator"
I am Canadian and have not heard that terminology before. Here is the link
http://www.justanswer.com/nissan/4ulhw-nissan-automatic-transmission-2-wheel-drive-first-gear-restarted.html
I live on an island in mexico and do not have access to any kind of real diagnostic facilities so I am on my own to solve this. If the gearbox attenuator is the trans control computer I can order a new one of those and be done.
Submitted: 2 years ago.
Category: Car
Expert:  Greg replied 2 years ago.
Name is***** goal is to provide you with excellent service – if you feel you have gotten anything less, please reply back,

Hi .

This is most likely to be the damaged valve body assembly , or even most likely the shift solenoid A which is part of the valve body assembly, this is inside the transmission..

Also a possible issue to cause this is the 3 speed sensors on the transmission ,if the speedometer is not working replace the Vehicle speed sensor.if working check the other two speed sensors ..

graphic

graphic

Going from your issue i would have these checked first before doing the TCC ,as when this fails you will have metal filings in the fluid in most cases .

Please get back to me if you need further assistance with this issue But please get back to me with the reply button, and not the poor or bad service, this way i can get back to you or suggest another expert if needed.

Kind regards Greg
Customer: replied 2 years ago.

So I cleared the stored codes on the car and drove it until it malfunctioned then checked the codes.

it gave me a 1574 which I believe is a vehicle speed sensor. My speedo is functioning properly though.

Expert:  Greg replied 2 years ago.
Hi Dave .

Can you recheck the codes as this code is :

P1573 code, This indicates the Powertrain Control Module has lost the communication with the Electronic Brake Traction Control Module .

Don't think this will cause you the problem you are having ..

VSS on your car Will be a P0500 code ..

Rgds Greg
Customer: replied 2 years ago.

Here is a link to the video I made of the light flashing after I followed the procedure in the ESM . Pretty sure it clearly shows a 1574.

Also I am in Mexico so maybe we do not have the same OBD codes here? I noticed in the ESM is says "EURO-OBD"

https://www.youtube.com/watch?v=7T8ba5gF1ZM

Expert:  Greg replied 2 years ago.

Hi Dave ,

Yes P1574 and not P1573 as you first said ,good .

Yes this is a speed sensor failure , if the speedometer is working you are going to need a scan tool with live data to diagnose this issue as this could be a ECM failure.

Possible causes :

  • Harness or connectors of the Communication Are Network (CAN),
  • Communication line is open or shorted.
  • Combination meter circuit is open or shorted.
  • Combination meter.
  • Vehicle speed sensor.
  • Transmission Control Module.

This will cause you the problem you are having .

Check the wiring connections first on the sensor and meter ,but this could be a ECM ot TCM issue if the speedometer is working ..

Please get back to me if you need further assistance with this issue But please get back to me with the reply button, and not the poor or bad service, this way i can get back to you or suggest another expert if needed.

Kind regards Greg

Customer: replied 2 years ago.

OK, do you have a location for the sensor? Is it on the trans or the engine? there is a sensor located on the trans in the front right corner not sure if that is the one.

The issue seems to come up more if we have had heavy rains and drive through puddles. If I can find the sensor I can clean the connections and apply some electric grease

Expert:  Greg replied 2 years ago.
Hi Dave

The one is the VSS as shown in the other post above, and the other is the meter in the .Instrument cluster , speed sensor could get water onto it with it being on the transmission. but check the wiring from the cluster to the VSS the two are not giving the same speed .VSS and cluster meter .

Rgds Greg
Customer: replied 2 years ago.

That picture above is not a great representation of my engine Trans combo is that supposed to be the Trans that the vss is depicted on?

Expert:  Greg replied 2 years ago.
Hi Dave, will get back to you with a better diagram .;-)
Expert:  Greg replied 2 years ago.
Dave the VSS is in the same location as the diagram you have above ...

Between the transmission and fire wall. (bulkhead).

Greg
Customer: replied 2 years ago.

I took the airbox off yesterday and pulled the sensor. It is in a very exposed location for the elements but the inside of the connector looked ok. I decided to run an experiment and replaced the sensor but left it unplugged.

Car runs and drives like normal, the only difference so far is that when you first start the car the first time it shifts into second it revs a little higher than it normally would but every shift after that is ok.

We have gone as many as 3 days without the car acting up so I am not convinced that it is ok yet. Interesting result though.

Expert:  Greg replied 2 years ago.
Hi Dave

Having the sensor disconnected will put the PCM into a back up mode and will give a set parameters and switch on the check engine light .

This also confirms the VSS is your problem .Wink

Please get back to me if you need further assistance with this issue But please get back to me with the reply button, and not the poor or bad service, this way i can get back to you or suggest another expert if needed.

Kind regards Greg
Customer: replied 2 years ago.

No CEL. The OD light blinks 16 times on startup to indicate a problem with the sensor.

What is the PCM? And how does it going into backup mode with set parameters help?

Expert:  Greg replied 2 years ago.
Hiv

PCM is the cars management system which controls the running of the engine ..

The system has back up system to keep the car running as near as normal as possible .

O/D light flashing is the same as the check engine light only for the managament system of the transmission . 16 flashers is most likely the flashing code for the VSS..

Greg

Related Car Questions