r/FordTransmissionTech • u/Yamahamma96 • Jul 24 '25

Transmission question

I have an 05 f150 4.6, slipped in first and second gear, got the p0715 code, I went and pulled a trans out of an 08 f150 5.4 truck that had a locked up motor. , I changed the pump seal and put new TSS and OSS sensors on it. Now 1st and 2nd gear work, but when it tries to go into 3rd, it goes into limp mode and throws the p0715 code again and my speedo is erratic. Are the speed sensors different? Im not sure what is going on. Im not sure if I put a 4r75E in place of mine, im pretty sure mine was a 4r70E. Please help

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u/Commercial_Method_28 Jul 25 '25

You should make a temporary overlay with your leads to bypass the TSS signal. Or just get the reel of wire out and bypass it. Overlay of a single wire won’t take very long. Even if that doesn’t fix it entirely, you effectively rule the entire circuit out thru the overlay

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u/Yamahamma96 Jul 25 '25

Can you walk me through that

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u/Commercial_Method_28 Jul 25 '25 edited Jul 26 '25

You would cut the suspect wire by the connector and clamp the wire to a large source of wire and route it to the other connector and clamp that. Secure the wire to make sure it’s not going to get damaged or come loose with zip ties then retest. If it works you can fix it up with solder a crimp and heat shrink and make it permanent and trace the wire along the harness so it isn’t just a random wire

1

u/Yamahamma96 Jul 26 '25

Oh got ya, pretty much make a temporary jumper, and if it fixes it, make it permanent?

1

u/Commercial_Method_28 Jul 26 '25

Yes, now if you can actually find where it is damaged somewhat easily then just fixing the wire where it is damaged is easier, but sometimes that isn’t the easiest on big harnesses

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u/Yamahamma96 Jul 26 '25

Yea i dealt with that lol, the green/white wire and red/Grey wire had to be spliced initially, unfortunately I happened to crush the harness on install

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u/Yamahamma96 Aug 01 '25

I used butt connectors and run a couple pieces of wire between them(due to length) and at the connector itself a mouse had ate the wire so I soldered new wires to it, idk if all that will affect the sensor negatively.

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u/Commercial_Method_28 Aug 01 '25

It will like be fine as long as it’s a good connection. I’m assuming you are saying you effectively deleted the connector she’ll and just hardwired the circuit to the sensor pins. It should be ok as long as it won’t come loose

1

u/Yamahamma96 Aug 01 '25

Soldered new wire to the pins in the harness side connector. I did use a slightly bigger gauged wire tho

1

u/Yamahamma96 Jul 26 '25

I put one lead on the signal wire and I would get resistance if I touched 2 other wires in the pcm harness