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View Full Version : code p0758 ,,,help plz



INDY500
February 16th, 2007, 01:32 AM
i got the code p0758 ..the trany wont shift up 3rd , and wont shiftdown ..looks like the converter lockup all time....,i check the wiring and the shift solinoides and its still not wrokn' ..., so something wrong with pcm ..cause that proplem appeared after swap the pcm .

joecar
February 16th, 2007, 06:00 AM
I have to research some of this... but if you swapped PCM, then you may have a bad PCM or a connection problem (bent pin).

I can't find that DTC...?

joecar
February 16th, 2007, 07:15 AM
Using the scan tool bidir mode, can you command the shift solenoids on and off...?

INDY500
February 16th, 2007, 10:58 AM
Using the scan tool bidir mode, can you command the shift solenoids on and off...?

i got scan tools, once i clear the code. the trans shift up , but its coming back dirctly .???

VT LS1 NZ
February 16th, 2007, 11:49 AM
Joecar given good advise you need to check that the shift solenoid is operating using BiDirectional controls.You may have already done this.

I would back track your steps to when it started happening ie PCM replacement.Personally it sounds like you have an electrical problem no power to shift solenoids.

Check pin 47 on your Red PCM connecter(J2-47 shift sol B) its a Yellow/Black wire.

joecar
February 16th, 2007, 02:38 PM
Indy,

With key on engine off, connect the EFILive Scan Tool, go BiDirectional->LS1/LS6 Control Panel->Transmission and command each of the 2 shift solenoids on/off and listen for the clicks...

select the GM.GEAR pid, press the red button (record) and view that pid on the dash/chart; this shows you if the PCM is commanding the solenoids; if you are logging and GM.GEAR does not change when you command a solenoid, then the PCM isn't working...

sanity check: command the fans on... do they come on and does GM.STATE06 show that they have been commanded...?

joecar
February 16th, 2007, 02:41 PM
P0758

Condition 1: PCM commands 2-3 shift solenoid on and voltage feedback remains high (B+).
Condition 2: PCM commands 2-3 shift solenoid off and voltage remains low (0V).

This means: the solenoid and/or it's circuit is shorted to ground/power/something or it's open.

Edit: check the ENG CTRL fuse.

INDY500
February 16th, 2007, 10:45 PM
Joecar given good advise you need to check that the shift solenoid is operating using BiDirectional controls.You may have already done this.

I would back track your steps to when it started happening ie PCM replacement.Personally it sounds like you have an electrical problem no power to shift solenoids.

Check pin 47 on your Red PCM connecter(J2-47 shift sol B) its a Yellow/Black wire.

the guy who checked the car by tech2 told me that the proplem in pcm softwear , cause the solenoids are wrokn' and there is electric connection...

ill check it by EFILIVE once i got it .

GMPX
February 16th, 2007, 11:59 PM
That pin is a multi use pin, it has different functions that can be configured within the PCM. Are you sure the 'swapped' PCM was exactly right for your car?

Cheers,
Ross

INDY500
February 17th, 2007, 08:32 AM
That pin is a multi use pin, it has different functions that can be configured within the PCM. Are you sure the 'swapped' PCM was exactly right for your car?

Cheers,
Ross


i guess yes ...i'll check it this weekend

joecar
February 18th, 2007, 06:01 AM
Ross is correct... PCM programmed for M6 will not work correctly on A4.

INDY500
February 18th, 2007, 06:31 AM
Ross is correct... PCM programmed for M6 will not work correctly on A4.

???? A4 ...??? how it comes .. i flashed it and tune to stock tune first than retune back to FI. im sure it was an A4 NOT M6 ???