P0770 Shift Solenoid Code

[funkified]

Was driving home from work yesterday when I noticed the trans shift weird between 3rd to 4th. It happened at a stop sign, got it to about 60km/hr and then watched my display as it shifted back and forth 3-4-3-4 and then it finally went up to 5-6th as i got up to highway speed.

Threw a code right after that and saw p0770 on my basic obd scanner.

I did a search on this forum and around google a bit. Seems like it could be a number of things like the solenoid itself, the valve body, wiring, or fluid levels.

From what I gathered this solenoid controls the shift to the higher gears (4-6) and is only actuated after 3rd, which would explain why it was hunting yeseterday.

Anyways, any experiences on this, what it actually was, and the cost to fix it at the dealer?

I did just get all of my driveline fluids changed less than 5000km ago so im thinking its one of the mechanical parts.

 

[CoronaRaptor]

Could be the lead frame. Was a problem for some in the 12-14 years, not sure what year yours is.

 

[CoronaRaptor]

I think there was a recall on it, might check with your dealer if its warranty, have heard it can be if you are under the 10 years 150,000 miles. Otherwise could be a 1500 bill?

 

[funkified]

i have a 13' and its definitely over that mileage, about 6000km over that coverage. Ill call the dealer and see whats up.

 

[FordTechOne]

P0770 sets when the PCM detects that the Shift Solenoid E (SSE) circuit failed open, shorted to ground or shorted to power. SSE is turned on in 3rd, 4th, 5th, and 6th gear.

If 1st, 2nd and 3rd gears are achieved, then SSE or the control circuit is open or shorted to power (no pressure)

If the truck launches in 5th gear, launch then the control circuit is shorted to ground (pressure).

Based on your symptom, SSE has failed in an open electrical state, or there is an open in the circuit between the PCM and solenoid. For reference, the resistance across SSE should be 17.5 to 18.6 ohms.

 

[funkified]

P0770 sets when the PCM detects that the Shift Solenoid E (SSE) circuit failed open, shorted to ground or shorted to power. SSE is turned on in 3rd, 4th, 5th, and 6th gear.

If 1st, 2nd and 3rd gears are achieved, then SSE or the control circuit is open or shorted to power (no pressure)

If the truck launches in 5th gear, launch then the control circuit is shorted to ground (pressure).

Based on your symptom, SSE has failed in an open electrical state, or there is an open in the circuit between the PCM and solenoid. For reference, the resistance across SSE should be 17.5 to 18.6 ohms.

if it has failed open, then it would mean that the truck would not shift out of 3rd at all then?

I still drove it this morning to work and everything was normal. Got up to highway speed and all the gears were shifting up and down smoothly. I have noticed some jerky shifts in the last few weeks with no codes. Maybe my solenoid is on its way out and has not completely failed yet.

 

[CoronaRaptor]

if it has failed open, then it would mean that the truck would not shift out of 3rd at all then?

I still drove it this morning to work and everything was normal. Got up to highway speed and all the gears were shifting up and down smoothly. I have noticed some jerky shifts in the last few weeks with no codes. Maybe my solenoid is on its way out and has not completely failed yet.

Have you checked the wiring harness where it goes into the transmission, that was an area of concern at one point, haven't heard about that in awhile on here.

 

[FordTechOne]

if it has failed open, then it would mean that the truck would not shift out of 3rd at all then?

I still drove it this morning to work and everything was normal. Got up to highway speed and all the gears were shifting up and down smoothly. I have noticed some jerky shifts in the last few weeks with no codes. Maybe my solenoid is on its way out and has not completely failed yet.

Yes, if the solenoid was open it would not be able to achieve 4th through 6th gear. It sounds like the solenoid may be failing when hot, or you have an intermittent circuit issue.

 

[jondle]

Have you checked the wiring harness where it goes into the transmission, that was an area of concern at one point, haven't heard about that in awhile on here.

I would start with this. The wiring harness for the transmission is routed directly over the exhaust manifold. If the clips holding the wire loom break, it can easily get too close to the manifold. Follow the wires from the transmission as they go around the manifold and look for any that are melted or frayed. This is a fairly easy self diagnosis before taking it in and paying for diagnosis.

 

[funkified]

thanks for the tips guys, ill check it out and report back