4r70w p0707 range sensor code help

[fishinman78]

I bought a 97 explorer 5.0 with 95k on it for a drive train swap in my Bronco and the transmission is stuck in 2nd gear.

It has a p0707 code which is the range sensor circuit low. I replaced the range sensor and cleared the code but its still stuck in second and code come right back.

Doing some additional research and it appears a bad PCM could be a problem or the range sensor is shorting to ground.

I pulled the transmission harness and inspected it and everything looks good. I tested all the wires going to the sensor for continuity back to where the trans harness plugs into the main harness and all is good there.

I pulled the pan and everything inside is fresh and clean and looks good.

I am hoping to get this issue sorted before I start taking it apart and having to troubleshoot after putting it in the Bronco.

The explorer runs great besides the transmission issue.

Any advice or guidance is appreciated.

 

[EFI Guy]

We need to know the PCM code for this one, the change happened in early 97. You could be dealing with one simple circuit, or 5.

 

[Drtj]

I am using a USShift 4 controller on a trebuilt 2000 explorer 4r70w from BV Broncos. It had a low voltage code on power to solenoid. Dropped pan and checked ohms on all solenoids and compared values provided by Kevin (USS), all were good. Finally found that trans case and USS passenger side connector had a week contact. Could be either connector but I think it was the trans side. I put a drop of solder on the connector for a better connection which solved the problem. Worth a look?

 

[Drtj]

I am using a USShift 4 controller on a rebuilt 2000 explorer 4r70w from BC Broncos. It had a low voltage code on power to solenoid. Dropped pan and checked ohms on all solenoids and compared values provided by Kevin (USS), all were good. Finally found that trans case and USS passenger side connector had a week contact. Could be either connector but I think it was the trans side. I put a drop of solder on the connector for a better connection which solved the problem. Worth a look?

 

[fishinman78]

We need to know the PCM code for this one, the change happened in early 97. You could be dealing with one simple circuit, or 5.

SLL4 is what the sticker on the firewall says and it does not have the original PCM. It appears to be a refurbished unit. F67F-12A650-TE is the part # on the sticker of the refurbished PCM

 

[fishinman78]

Finally got my forscan adapter today.

Definitely a problem with the transmission range selection.

Computer is seeing
0 volts in park and commanding OD
1.63 volts in reverse and commanding 2nd
1.63 volts in neutral and commanding 2nd
1.63 volts in park and commanding 2nd
0 volts in man 2 and commanding 1st
0 volts in man 1 and commanding 1st

I am attaching screenshots of the data

Not sure where to go from here

 

[fishinman78]

Found some testing info online in an explorer manual.

Performed a series of test based on the range sensor code if im understanding this correctly it seems like I have shorts in the system

The two tests at the sensor harness are within spec. Less than 5 ohms but the tests at the PCM all seem to have failed

 

[EFI Guy]

Does the plug for your range sensor match what is shown in the picture, as in 12 pins and rectangular?
SLL4 (which matches the part number you gave) Uses an 8-pin oval-shaped range sensor, not the 12-pin pictured.
The resistance values are different between the two and the 12 pin has additional circuits that SLL4 will not use.

What does Forscan show for the strategy of your PCM? It will be CTBAF or CQBA3 or something similar.
It shounds like the transmission and transmission harness were swapped at some point.

 

[fishinman78]

Does the plug for your range sensor match what is shown in the picture, as in 12 pins and rectangular?
SLL4 (which matches the part number you gave) Uses an 8-pin oval-shaped range sensor, not the 12-pin pictured.
The resistance values are different between the two and the 12 pin has additional circuits that SLL4 will not use.

What does Forscan show for the strategy of your PCM? It will be CTBAF or CQBA3 or something similar.
It shounds like the transmission and transmission harness were swapped at some point.

First off I gave some bad info. This is a 1997 mountaineer 5.0 AWD. (Early 97 has the GT40 3 bar heads and a late 96 build date on the vin tag) I forgot and thought it was an explorer. Not sure if that matters.

Yes the range sensor is 12 (11 really because one is not used) when I got the P0707 code I decided to replace the range sensor and when I went to the parts store they gave me the 12 pin which matched what was there.

I can confirm that the transmission has the soft harness and not the molded one inside

Strategy code is GTBAFG6

 

[DirtDonk]

Almost sounds like somebody programmed a trans brake into the mix! Ha ha!
Look for a button somewhere in the harness.
Just kidding, but from your description of things trying to be in park and overdrive, and all kinds of stuff at the same time made me think of a trans brake.

But for now, it sounds like you need either a different computer to match your current range sensor, or a different range sensor to match your existing ECU.

 

[fishinman78]

Almost sounds like somebody programmed a trans brake into the mix! Ha ha!
Look for a button somewhere in the harness.
Just kidding, but from your description of things trying to be in park and overdrive, and all kinds of stuff at the same time made me think of a trans brake.

But for now, it sounds like you need either a different computer to match your current range sensor, or a different range sensor to match your existing ECU.

I'm starting to think someone replaced the range sensor with a 12 pin and it was originally an 8 pin and then they got a later model 12 pin harness to match the new 12 pin range sensor.

Going to pull the transmission wiring harness back out and check the wiring

 

[EFI Guy]

You definitely have a mismatch, 96 PCM, 97 range sensor. Check your PCM connector, if it has wires in 3, 49, and 50 then just using a 97 computer will solve your problem.
Odds are pretty good that I could flash that computer to 97 and that would also work. 96 and 97 share the same hardware code, it's the software that is different.

If you are missing those pins on your PCM connector then you have an early harness and I would swap the trans harness and range sensor to a 96.

 

[fishinman78]

You definitely have a mismatch, 96 PCM, 97 range sensor. Check your PCM connector, if it has wires in 3, 49, and 50 then just using a 97 computer will solve your problem.
Odds are pretty good that I could flash that computer to 97 and that would also work. 96 and 97 share the same hardware code, it's the software that is different.

If you are missing those pins on your PCM connector then you have an early harness and I would swap the trans harness and range sensor to a 96.

No wires in pins 3, 49, or 50.

The wiring for those pins come out of the range sensor and dead end at the screw together connection by the transmission.

I ordered an 8 pin range sensor from a 96 explorer with the connector harness and will rework it to match the SLL4 computer requirements. Fingers crossed

 

[fishinman78]

Got the new range sensor installed.

I can see it correctly displaying the gear I am shifting into and I can see it actively commanding each gear as well. Which it was not doing before.

The solenoids are opening and closing at different times as needed and I have no more fault code...but still stuck in 2nd gear.

I think I have exhausted all wiring options unless there is another recommendation.

I guess I am going to drop the pan and look at the valve body now.

 

[EFI Guy]

You need to look at the solenoid connector now. There is a diagram for it where you found my range sensor diagram. The transmission may be 98 or later which has a different pinout. Repinning that connector may be all that you need to do.

 

[fishinman78]

You need to look at the solenoid connector now. There is a diagram for it where you found my range sensor diagram. The transmission may be 98 or later which has a different pinout. Repinning that connector may be all that you need to do.

I did check resistance between pins 1&2 and 1&6 and got something like 25-28 ohms for both. So I assumed the wiring was correct at this connector

 

[EFI Guy]

I would just use a mirror to look into the connector at the trans and count the pins. That will tell you what year range it is, then look at the colors on your plug.

 

[fishinman78]

Victory!

I pulled the valve body last weekend and it turns out someone was previously in there. I took every valve/sring/etc out and clean and inspected. It turns out they had the 2-3 Capacity modulator valve in backwards. Put it back in correctly and we are moving forward in all 4 gears!

Thanks to @efiguy for the help on the range sensor, because that was the main problem. I think having the wrong range sensor sent them into the valve body and things went south from there!!

 

[DirtDonk]

Way to go! I know it’s hard to dig into something that is already put together.
But once we get past the mental and emotional resistance (very big for me!), apparently things start to fall together!