# shifting and speedo problems



## lilblucoupe (Aug 8, 2006)

i just bought a 95 xe v6 auto, it shifts really hard. a mech told me it was bc it has a bad vss cause the speedo doesnt work. the odomter does though. but maybe i just notice it moving sometimes..idk. I think the kid i got it from took the cel out cause i dont see it light up. So could the VSS be the problem with my shifting so hard???


----------



## zanegrey (Dec 5, 2005)

read the cticky and read the codes...


----------



## lilblucoupe (Aug 8, 2006)

i guess i gotta replace or find out why my cel isnt working first too


----------



## zanegrey (Dec 5, 2005)

read the stcky..

and read the codes..

the codes are not read from the cel..

they are read from the ecm...


----------



## lilblucoupe (Aug 8, 2006)

i did what the sticky said. i turned the key on, move the dial to dia waited for the 3 flashes and then put it back counter clockwise to low idle setting,and i got 55 thats it


----------



## zanegrey (Dec 5, 2005)

did you check the tcu ??

that is the trans ecm...


----------



## lilblucoupe (Aug 8, 2006)

how do you do that???


----------



## zanegrey (Dec 5, 2005)

i will check on that..

meantime did you check mode 4..


Mode IV - Switch Operation Monitor
-----------------------------------------------------------------------
Use Mode IV to determine if the Throttle Position Sensor (TPS), Starter circuit and/or Vehicle Speed Sensor (VSS) are in proper working order.

Turn the ignition switch on, but do not start the engine.
Turn the dial on the ECU fully clockwise. After the LED flashes 4 times, turn the dial fully counter clockwise.
Make sure the RED LED is turned off.
Make sure the RED LED turns on when depressing the gas pedal. If not, check or replace the Throttle Position Sensor.
Make sure the RED LED turns on when turning the ignition key the START position. If not, check or replace the starter.
Drive the vehicle with the ECU unbolted and within view. Make sure the GREEN LED turns on when speed is 12 MPH or more. If not, check or replace the Vehicle Speed Sensor.


----------



## lilblucoupe (Aug 8, 2006)

i did the press the gas pedal down and the red led lit, but i didnt drive it. so i guess i should do that


----------



## zanegrey (Dec 5, 2005)

while you are at it check the vss plug in for correct conection or corrosion .check for broken or cracked wiring..


----------



## lilblucoupe (Aug 8, 2006)

anyone else?


----------



## smj999smj (Jan 1, 2006)

Mid 90's Nissan had a lot of issues with speedo heads. There are threaded inserts at the back of the speedo head unit where the screws thread in that mount it to the back of the cluster housing, as well as create the contact between it and the printed circuit. Cracks can develope in these inserts that can cause an poor electrical contact, sometimes intermittant. The vss generates and sends an AC voltage signal to the speedo head, where it's converted to DC. The speedometer drives the odometer and also sends the signal to the ECM. If the speedometer and odometer don't work, it could be the VSS, the circuit betweeen it and the speedo head or the head unit itself. You need to check for a good signal to the back of the head unit. If the odometer is working but not the speedometer, then you know the speedometer is getting a good signal, thus the speedometer head unit is faulty.


----------



## lilblucoupe (Aug 8, 2006)

im really more worried about the shifting than the speedo


----------

