P0715... need some info

[My92Ranger]

Sorry, didnt realize we had a dedicated transmission forum.

Anyway here is my problem.. just gonna copy and paste from the thread i made in the 4.0 forum. If a mod wants they can delete that one since I will probably get the best help here.

Got a 97 B4000 4.0 auto 2wd.
Went to get it inspected and it failed emissions for a p0715 turbine speed sensor circuit malfunction.
I know this is inside the transmission and I will have to pull the transmission if it is the sensor but I want to test it. Does anyone know which wires at the main transmission connector go to this? Id like to OHM them at the connector rather than drop the pan and try to find a 2 wire plug somewhere inside the pan (any info I have found in a search doesnt show a pic or anything of where the plug is nor have any of my searches came up with the wiring colors)

Would appreciate any help. Thanks

Also I came across this post and wondering what that means? Is my 97 not supposed to have a tss?

Also depends on what year tranny you put in as they did away with one of the tss sensors for the OD drum in 1997 and up models.

 

[BRUTUS_T_HOG]

1. Disconnect the PCM connector and check resistance between the Dark Green/White (DG/W) wire at pin 84 and the Grey/Red (GY/RD) wire at pin 91. Resistance should indicate 64-126 ohms.

2. If resistance is within range, check the DG/W wire for indication of resistance to ground. The circuit should indicate an open reading to ground.

3. If resistance to ground is indicated, disconnect the transmission 16-pin connector and verify that the resistance to ground then reads to be open indicating a problem inside the transmission with the sub-harness rather than in the harness between the PCM and transmission connector.

4. If the resistance reading in step 1 indicates an open reading, disconnect the transmission 16-pin connector and check the DG/W wire to verify it is complete between the PCM and the transmission connector.

5. Check both GY/R wires to pin 91 to verify both GY/R wires are good.

6. Replace the Turbine Shaft Speed (TSS) and/or transmission internal sub-harness as needed to service the circuit.

7. If the resistance reading between the circuits indicates to be good, monitor the DG/W wire for an AC sign wave signal when the engine is running as the code sets on acceleration. If the signal is consistently present to the PCM connection, replace the PCM.

The TSS is internal of the transmission and is secured to the forward side of the center support. Replacement of the TSS will require removal of the transmission and its internal components as far back as the front ring gear and one-way clutch.

 

[My92Ranger]

Dang.. shoulda checked back BEFORE I dropped the pan. LOL
Just got done dropping the pan and still dont see the connecter but knowing the wire colors will probably help me locate it. The only one I see with two wires is right up above the valve body and im not sure I can get to it to check anything.

Either way thanks for the detailed help.. hopefully it will help someone in the future as well as me

 

[My92Ranger]

Gah! I messed something up... LOL.
I just wanted to get the dang thing through emissions. So I checked the resistance at the main transmission connecter and it was 84 OHMS. I checked the two pins at the ECM and it was infinite. So I ran two new wires from the ECM to the transmission main connector and it OHMS at 84 at the ECM on the two wires that I ran. That should be good... but it isnt.

I guess I got the wrong wires or something cause now instead of my one TSS code I got 4 codes and my O/D light is flashing.
Here are the codes.. hope someone can give me input on what went wrong here.

P0708 Transmission Range Sensor Circuit High Input
P0113 Intake Air Temperature Circuit High Input
P0118 Engine Coolant Temperature Circuit High Input
P0123 Throttle/Petal Position Sensor/Switch

But no P0715 TSS sensor code.. LOL.

Where would you think I should go from here? I would assume maybe I found the wrong pin in either the ECM or Transmission connector but I cant be sure without having a full diagram. I connected to pin 84 and 91 at the ecm end. On the transmission end I didnt have a pin number to go by so I just went with the same color.

 

[BRUTUS_T_HOG]

did you hook up your 2 new wires backwards?

1

2

3

 

[My92Ranger]

Im almost certain I did not. I will verify it though.

 

[My92Ranger]

According to your diagrams the other grey/red wire in the main trans connector would be the temp sensor. Certainly crossing that up shouldnt cause the other codes that appeared after I made these wires. Im done with it for tonight.. if you come up with any other ideas please let me know. Gonna start with a fresh slate in the morning. Its been 102 degrees today and a heat warning and I think my brain is boiled

 

[My92Ranger]

So does anyone have a diagram of the main connector at the transmission that shows which wire is which?

 

[My92Ranger]

Nevermind I got it figured out. Kind of.
After fixing the wires and getting the resistance right I didnt check resistance to ground. It does have resistance to ground (the same 84 it has to the grey wire) It needs a sensor.

As for the other sensors when I bypassed the grey wire it also bypassed that signal to the rest of those sensors.

I gave up and fixed the wire to the other sensors and jumped through the hoops to get an emissions waiver. Thanks for all of the help.

 

[BRUTUS_T_HOG]

ouch. so it needs a TSS? well at least you got it sorted out