bmac6996

A string a bad luck with this car, but this is the one you guys can help.

ECL comes on and I took it to Autozone and pulled the code. One code only, P0715.

Look it up and looks like it is the "Input/Turbine shaft speed sensor circuit".

Here is what's been happening before the ECL came on:

On a cold start, the car sounds like it's making a whinning sound. Doesn't sound like a circular sound like a belt.. just a high pitch sound. When reversing (to get out of parking space) in the morning, when shifting into Reverse, it does not go into gear right away, take about 5 seconds to get in. When I then switch to D4, it takes another 5 seconds and then it goes. When driving during a cold start it doesn't easily shift between the gears. Once the car warms up, the whinning noise and the gear shift fine.

Now this morning I was in somewhat in a rush and didn't let the car warm up. So I drove it, kinda revin more than I should during a cold start and bam, the ECL comes on.

Now again, once it's warm it shifts fine. Not stuck on 3rd gear or anything. Tried clearing the ECL and it comes back up right away. Just only in the morning (cold start).

Now here is my question, what are the chances of it being the speed sensor VS a bad transmission with the information I provided? I know there is a Service bulletin, but if it's not the sensor, Honda dealership would charge me the full diags fee for something I already know. I am looking for people who have seen and experience this issue. I need to plan for a new car VS just only a sensor. (car is over 10 years old, I am not going to invest huge amounts in the car anymore)

Thank you ahead of time

-bmac6996

craiger28

Well the first thing you could do is to take off the sensors/relays on the transmission and look at the screens to make sure they are not blocked/clogged up with crap. If so clean them and put them back on tranny. See what it does then after you clear the codes. If that doesn't work, you are probably looking at a rebuild or replace on your tranny.
I have 1 question for you. Does both the fans (condensor/radiator) work, have they been working or has one gone bad in the past and you waited a while to replace it?

bmac6996

The fans both work. Neither of them have had issues. The only long shot is my thermostat went bad and cause the fans to not cool correctly but that was fixed right away.

Where would the speed sensor be? Any good pictures?

bmac6996

bump.

anyone??

accord2nrz

What year is your car? I will pull a screen capture from my shop manual and post it for you.

bmac6996

Honda Accord 1997 4 Door EX 2.2 VTECH

accord2nrz

I've uploaded the picture of the VSS for you.

www.diytuning.com/hondatechhelp/vss.pdf.

if you go to your car, remove the cold air intake if u have one and look down towards the back sitting ontop of your transmission. that's where it is. the connector is 3 prong. be careful taking it off.

Vtec_Hustlr

This is an old thread, but I'm having this p0715 code as well. My friend 96 prelude had this code and I replaced the main-shaft input sensor. Some days CEL would come back on and after clearing code, it will stay off for over 30-40 miles and comes back on. I've noticed the tranny is slipping from 1-3 gear/ RPM seems harsh with symtoms such as: jerking, late shifting. After 3rd gear, it'll be smooth. ( Automatic). I recently replaced the ATF fluid and code still came back. I fixed a p1491 code and cleared code. So far 40miles, no codes yet. Can anyone confirm if tranny is going bad? Car is like 260xxx miles.

MAD_MIKE

If the trans is shifting late/harshly and the 715code, pull the sensors out of the right side cover and verify they are clean. If they are sludged up this will affect shift quality, but will not cause slipping.
When was the last time the fluid was changed?

Vtec_Hustlr

Im not sure which sensor your referring to. There's only one that I can physically see and is attached to the transmission. I'm certain it is not the VSS sensor cause speedo and odometer reading is fine. I did notice when I pulled out input sensor, some of the liquid is on tip. I assume that's normal? I don't know when it was last replaced but I went ahead and replaced the ATF. I did check for continuity and 12V ref which seems to be good. I noticed that on the connector, one of the female terminal was very black. Used the multimeter end to scap off the spots to get good electric contact. Since I've fixed the issue EGR and passed inspection, p0715 code hasn't come back on however late shifting or jerking is still there. It's kinda odd...

MAD_MIKE

VSS is at the rear near the firewall.
NM and NC sensors are located on the right side cover, they can be seen if the right wheel is turned to the right and you look behind it at the right side cover of the transmission. TCU uses these to monitor shaft speeds to know when to command an upshift. VSS is used for downshifts.

Vtec_Hustlr

Hey Mike,

Do you have a drawing/diagram ?

I saw your comment on this thread " https://honda-tech.com/forums/honda-accord-1990-2002-2/97-accord-2-2l-150k-miles-3006412/" but the gif is no longer there.


Below is picture of what believe is the main-shaft sensor and was replaced but 715 code is still showing. Correct me if I am wrong.
96 Prelude Speed Sensor -- Main-Shaft?

MAD_MIKE

That does appear to be the mainshaft sensor connector, it should be mounted on that windowed tab above the cooler lines.
Countershaft connector is mounted behind the starter.

Just because a code is set does not mean the sensor itself is bad, on higher mileage transmissions without fluid changes the sensor gets gunked up with ferrous material(it is a halls effect sensor) loss of resolution = code. If the connector, pins or wiring is corroded or damaged then this will also set a code. Check for continuity from sensor to TCU, sometimes the pins break off inside the connector and everything appears to be fine. Also verify that the main grounds and bonding jumpers are clean and tight as well. With the TCU connector off you should be able to back probe and read the sensor resistance, if you have an open or short then the wire harness may have been damaged.

NM and NC are located on the right side cover, # 15 and #16