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Discussion Starter · #1 ·
Been reading a lot on the forum in the past year but have never posted anything. I have an 06 mods in my sig, had it for 3 months.

Noticed last night driving home and this morning coming to stops that the trans had hard downshifts and wondering why. Continued to drive it when all of a sudden the back wheels lock up when it downshifts to first at a stop light.

So i pull over, engine light comes on, put it back in drive, just revs up. Finally get it to stay in gear and limp it over to a parking lot where it sits now.

Used Edge Insight to check codes and its giving PA0700 which I have found to be that of limp mode. What should I be checking? I cleared the code but still afraid to drive it. Should I change the spin on? Fluid looks good btw. Wasnt running her hard either.

Also, the tranny temp spiked right before I pulled over from about 140 to 260 if that makes a difference. Maybe an NSBU switch?
 

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P0700 has nothing to do with limp mode. All that code is the trans computer telling the engine computer to turn on the check engine light. You need to get a scanner that will read the tcm to get the real codes.
 

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Discussion Starter · #3 ·
Oh ok that somewhat makes since. So is there a way I can do it on the edge or would I have to take it to someone with an autocal or other scan tool? I thought that was the whole point of the diagnostic testing part of the Edge Insight.
 

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The edge can't read the TCM. You could take it to a dealer and have them use a tech 2
 

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Discussion Starter · #5 ·
Aleight thanks sounds good luckily i have good AAA so i can tow it for free. Any other ideas of what it could be regarding the way it had been shifting before the incident? Like i said the trans fluid level looks good and it had a new spin on filter within the last year put on so i dont think thats the issue. Ive read about the nsbu going bad anyone have any experiance with this?
 

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Discussion Starter · #6 ·
The more I read pretty sure its something to do with the IMS Switch (Internal version of the NSBU switch for LBZ and up).
 

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You're just guessing without having the codes read.


$10 Ally filter never hurts.
 

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Yep no point guessing. Get it in and get it looked at.
 

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Discussion Starter · #9 ·
Alright well i did the inevitable and had it towed into the stealership. They put their scanner on it and got codes for the pressure control selenoid and the shift selenoid. Can't work on it til tomorrow so I have some time.

What causes this and is it just a simple replacement of the selenoids or is their anything else that will need to be done?
 

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Discussion Starter · #10 ·
Bump
 

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Discussion Starter · #12 ·
Sorry never got back Mike it was at the dealership and never got the codes from them.
Anyways, got it back today. They replaced a wiring harness in the trans and a selenoid (evidently shorted out our something). They told me it shifted funny at first after getting all back together (also flushed and put new spin on) but as they drove it it got better. Well I picked it up and it feels fine until the 4th to 5th gear shift. Even with a light pedal (1/4 down on economy tune) it will rev up about 200 extra RPM before shifting into 5th. Almost like its going into neutral. It pisses me off that they say they fixed it and its still having problems. They think it's relearning which may be but I wouldn't think it would shift like this in relearn.
Do you think maybe Clutch 5 is burnt up or do you think they fixed the wrong thing? They never said there was shavings or anything in the oil. I'm going to try and give them a call tomorrow and talk to the guy that worked on it but just trying to get a little input or knowledge before I talk to them. What should I ask? No lights or anything are on btw.

Thanks
 

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Discussion Starter · #13 ·
I also replaced the fuel filter this afternoon for shits and gigs because i know sometimes those can cause some funny issues with no luck. All drives good except that one shift
 

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Discussion Starter · #14 ·
Bump
 

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Discussion Starter · #15 ·
bump anyone? talked to the mechanic today and he said there wasn't shavings in the pan when he took it apart.
 

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Discussion Starter · #16 ·
Alright still hasnt been diagnosed. Replaced a selenoid still get codes p0741 and p2723. Maybe speed sensor problem or tcase possibly?
 
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