Here's the problem. The other day, my Explorer gave a hard jerk while changing into 2 (maybe 3rd?) gear. Never happened before. I was under 20 MPH & had just stared it. (My speedometer works as do all the dials.) My Check Engine light came on & when I had the code pulled it read quote "P0715."Transmission Speed Sensor circuit condition. Vehicle speed above 15 MPH while transmission output shaft speed below 60 RPM. Possible cause Failed transmission speed sensor or electrical problem"
I got a Transmission Speed Sensor, (which I haven't put in yet), and was told that this would solve the problem. My question is twofold: Is there ANY chance this is a false or misread code and the problem is something else? And could ANOTHER sensor attached to the transmission be the cause? (How many sensors are on the tranny?) All I've read about this problem, say's replacing the Transmission Speed Sensor is preceded by the SPEEDOMETER quitting, but mine works fine.
The truck is a 1997 Explorer 4x4, but I don't use 4x4. In fact I've driven it without the forward drive shaft ever since I had the BW4405 Transfer Case replaced. Not looking forward to fooling around with the TC again. Thanks in advance for any & all responses.


Chris.

 

Clear the code, and see if it returns...

.... Philip

 

I cleared the code and drove it for several days. The Tranny once again started doing the same thing and the Check Engine light came back. I replaced the sensor, but after 30 minutes driving the same symptoms occurred & the Check Engine Light came back on. I took it to have the code read & sure enough, the same PO715 code with the same explanation Not sure where to look next. Any other sensors on this transmission & TC that I need to check? It's starting to get on my nerves.

 

I think they sold you the wrong speed sensor. The P0715 code is related to the Turbine Shaft Speed (TSS) sensor. Since you commented that the failure is often preceded by the speedometer stopping, I suspect you were sold a vehicle speed sensor, which is different from the turbine shaft speed sensor. The TSS should have a resistance between 64-126 ohms. The Output Shaft Speed sensor resistance should range from 305-735 ohms. The TSS sensor is mounted internally to the transmission on the center support whereas the OSS sensor is mounted externally on the left rear of the transmission.

-Rod

 

Thanks' for the reply. Not only do I think the part they sold was wrong, but it didn't fit in either. Used an extra one I had from my old TC. Anyway the fact that the TSS is INTERNAL fills me with dread. I'm not relishing the thought of pulling the Transmission apart. However, where exactly is the TSS located inside the transmission? Can it be gotten to by removing the pan, filter and valve body? If so, then that's something I can do. Thanks again for you reply.


Chris

 

You don't mention if you have the 4 speed or 5 speed transmission. I'll assume this is a V6 Explorer and therefore has the 5 speed automatic.

The TSS electrical connector can be accessed with the pan and filter removed, but to replace the sensor you have to disassemble the transmission. It's probably worth checking the sensor resistance before digging that deep.

-Rod

 

Hey Rod. Yes the engine is a V6 SOHC with the 5 speed tranny. At this point, from what you're saying, I'm assuming the transmission is going to have to be rebuilt. Also, the OD hasn't worked for some time but I haven't had to use it, but I know that nothing happens when the OD button is pushed on the gear shifter. the light doesn't come on. Would this play any part in my transmission shift problem?


Chris

 

The OD not working and the light not coming on may be due to a broken wire in the steering column or shift lever. That seems to be a relatively common issue as well.

I'm no transmission guy so discussion the TSS issue with someone familiar with these transmissions is probably best, but from what I saw in the service manual it does seem like if you're going to replace the TSS you may as well have the entire transmission gone through at the same time. It appears like it has to come almost halfway apart to get to the TSS.

-Rod

 

Thanks' for your reply Rod. I was asked whether or not I'd had the ODS delete on my truck. I've no idea. I did find a TSB about that on this forum and I'm wondering if this procedure would solve my transmission problem. I won't know until I get under the vehicle and see if it's still connected. If it is I'll unplug it & see if that solves the problem. If not then I'll have to go the rebuild route, which is something I'm not looking forward to at all.


This is the article:


Article No.
97-15-28 07/21/97
TRANSMISSION - 5R55E - OVERDRIVE DRUM SPEED
SENSOR DELETED - SERVICE TIP LIGHT TRUCK:
1997 AEROSTAR, EXPLORER, RANGER ISSUE:
The Overdrive Drum Speed (ODS) sensor has been deleted as a running change. This may cause the Powertrain Control Module (PCM) to receive stray signals from the non4unctional ODS sensor that may affect the operation of the transmission.
ACTION:
Disconnect the ODS sensor connector, Cut off the connector end and splice the wires together. This should reduce the possibility of stray signals affecting the operation of the transmission. Refer to the following Service Procedure for details. SERVICE PROCEDURE


<table cellspacing="2" cellpadding="1"><tbody><tr valign="top"><td>1.</td><td>Disconnect the ODS sensor connector from the sensor. </td></tr><tr valign="top"><td>2.</td><td>Cut off the connector end. </td></tr><tr valign="top"><td>3.</td><td>Splice and solder the two (2) wires together. </td></tr><tr valign="top"><td>4.</td><td>Shrink wrap the wires and secure the wires to the harness. For proper wire splicing techniques, refer to the Augat Connector Repair Kit Manual. </td></tr><tr valign="top"><td>5.</td><td>Leave the sensor installed if using the original case. New service cases will not have an ODS sensor hole in the case. </td></tr></tbody></table>
PART NUMBER PART NAME

F77Z-7005-DD Transmission case OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper WarranW Coverage

OPERATION DESCRIPTION TIME

971528A Eliminate Overdrive Drum 0.3 Hr.
Speed (ODS) Sensor
Connector As Outlined DEALER CODING
CONDITION
BASIC PART NO. CODE
7005 12 OASIS CODES: 501000, 502000, 504000


I'm guessing the ODS sensor became redundant or no longer necessary, which is why it was deleted. I'm hoping that it's absence as a functioning part won't cause any problems, that is IF it's still plugged up. I'll have to see this weekend.