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Discussion Starter #1
So the manual side of my tranny stopped working while driving the other day. I used it to downshift and pass a fool and it just stopped working. No CEL or anything came on. Also i noticed that my cruise control isn't working.
I tried disconnecting the neg battery terminal overnight but it only went into manual mode long enough to park the car. Don't know if CC ever came back but i tried it again and the second time i left the neg terminal off, it didn't even go back to manual mode again.
It drives fine in automatic mode besides the lack of CC its completely normal. Are there any other tricks i can try before i take it to the dealer?
Oh and when it went into manual mode the radio said something real quick like Crossing or something. I didn't catch what it said. Maybe its a clue maybe not... :)
 

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I don't use manual mode for this reason. I figure it's more complicated than Drive, and I don't even know how to use it properly. I'm the kind of guy who deals with blistering heat instead of turning on the AC because I feel like it will improve the life of the vehicle. I would think you have to be at 0 MPH to switch over to manual mode, but I haven't read up on it yet.
 

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Slick Black Pontiac
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This is a weird thing you're describing.

I use the manual mode on my 05 GT once in a while. From what I understand you can shift into this mode at any time and at any speed as it is not a truly "manual" mode, it is instead a self selected automatic mode. I don't know if you noticed but when you press on the brakes and come to a stop in manual mode it automatically downshifts to 1.

Having owned both manual and automatic cars I prefer a true manual with a clutch, the system on the G6 is slow and clunky. The only thing it is really good for is engine braking when going down very long hills, or holding gear through a turn.

I'm pretty sure that the shifting part is electronically actuated either at the base of the shifter in the car or on top of the transmission where the shift cables connect. You could take a look and see if there is anything stuck there like a pinecone or something, otherwise its probably an electrical fault.
 

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Slick Black Pontiac
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I don't use manual mode for this reason. I figure it's more complicated than Drive, and I don't even know how to use it properly. I'm the kind of guy who deals with blistering heat instead of turning on the AC because I feel like it will improve the life of the vehicle. I would think you have to be at 0 MPH to switch over to manual mode, but I haven't read up on it yet.
Just a quick note, if you don't run your air conditioning once in a while it will seize up the compressor. (also note that in winter when you run the defroster the Ac runs to dry the air so that you don't get worse fogging.) Cars these days are much smarter than they used to be, you can even leave it on when you start the car since the clutch is electronically controlled and when you start the car it automatically shunts all the power to the starter motor. This is quite handy if you have remote start and want to get into a nice cool car after a hot day at work.
 

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Thanks for the tip. I run my AC when I have passengers or take trips that are more than five minutes long. My daily drive is 5 minutes here and there. :p I'll have to read for myself that you can switch to Manual at any time. I figured it was something like enabling 4 wheel drive where you have to be at 0 MPH.
 

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Slick Black Pontiac
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Thanks for the tip. I run my AC when I have passengers or take trips that are more than five minutes long. My daily drive is 5 minutes here and there. :p I'll have to read for myself that you can switch to Manual at any time. I figured it was something like enabling 4 wheel drive where you have to be at 0 MPH.
Yeah, the manual mode in these cars is more of a computer shifted mode, the transmission won't let you downshift if the revs are too high. Also, if you pull it over into the manual mode, the gear you are in will show on the dash under the speedometer. It definitely won't hurt anything no matter how fast you might be going since it just shows what gear you are in at that moment. About the only thing it will do is make you want to drive faster and more aggressively because it makes the car feel sharper somehow, I think it speeds up throttle response and shortens shift times a bit as well.
 

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Sorry its a 07 GTP with the 6 speed tranny. And yea i would prefer a true manual over this mickey mouse bs. But hey what can you do right?

07 G6 GTP with 6 spd
cruise control inoperative
manual shift mode inoperative


I have no clue regarding this: "...when it went into manual mode the radio said something real quick like Crossing or something."

Do you know if these two issues happened simultaneously or is it more like you noticed one & then some time later the other?

So you push the CC enable button & the lamp stays off?
 

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Discussion Starter #11 (Edited)
07 G6 GTP with 6 spd
cruise control inoperative
manual shift mode inoperative


I have no clue regarding this: "...when it went into manual mode the radio said something real quick like Crossing or something."

Do you know if these two issues happened simultaneously or is it more like you noticed one & then some time later the other?

So you push the CC enable button & the lamp stays off?
The radio thing could be nothing, it happened quickly and i saw it out of the corner of my eye. It could have said cruising or anything really. Honestly its probably nothing. But i thought i'd mention it in case someone had noticed something similar. The message happened after i disconnected the neg terminal overnight when i was moving it from on the drive way to the street. This was the last time the manual portion of the transmission worked. Subsequent attempts to disconnect the neg battery terminal to "reset" things did not work.
The Cruise control lamp/button is not working and didn't work even after the battery terminal trick. It used to work before the whole transmission thing. Now i push CC enable button and nothing happens, the lamp stays off. Issue's happened simultaneously. No manual mode transmission and no CC.
Here is a timeline that might help make things clearer;
Car works fine-------Manual Transmission and CC stop working for no apparent reason while driving---fuse box looks good--disconnect neg battery terminal overnight---reconnect battery terminal, manual tranny works but only for the first drive, CC doesn't come back. Mysterious message appears on radio display---No CEL has appeared at anytime, old man has his neighbor hook up an OBD2 reader says something about a CC switch malfunction. I'm not given a code or anything further than "possibly a bad CC switch or malfunction" and he was unable to clear the error that he saw----- I go to Advance Auto to get actual code.--no code to give and no error messages of any kind.----CEL comes on today and now remote start doesn't work-- need to get code--dealership wants to wait a week before seeing me.
That's where I'm at now. Hope that clears things up. I'll post the code as soon as i get it.
What i'm hoping is that somehow this CC switch or whatever has generated an error and just needs to be replaced vs something wrong with the transmission that turned off the CC.
 

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Discussion Starter #12
the CEL was just a small evap leak, nothing to do w/the transmission. guess i'm headed to the stealership.
 

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Discussion Starter #13
back from the stealership

well the dealer has provided some insight. What was wrong was error code P0826 Tap Shift Fault.
Well that sounds right to me. Cept the tap shift module is integrated into the Shifter Assembly and thats a cool $800.
Then if the gods spit on me and curse my G6 the next step would be to replace the TCCM and valve assy, which would cost and i quote "crazy stupid ugly money. you don't want to go there."
Hopefully i can find a way to fix this without spending $800 bucks.
 

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Dont know if this could be the problem but might wanna try before you shell out money for the repair. Since you said you have problems with cruise control it reminded me of the issue with corrosion on the bcm connections, might wanna just try rubbing some dielectric grease on them and then disconnect the battery and see if that helps.
 

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well the dealer has provided some insight. What was wrong was error code P0826 Tap Shift Fault.
Well that sounds right to me. Cept the tap shift module is integrated into the Shifter Assembly and thats a cool $800.
Then if the gods spit on me and curse my G6 the next step would be to replace the TCCM and valve assy, which would cost and i quote "crazy stupid ugly money. you don't want to go there."
Hopefully i can find a way to fix this without spending $800 bucks.
I don't have a simple fix. It requires old fashioned analog troubleshooting:

P0826
Inspect the fuse in the ignition 1 voltage circuit for an open.
⇒ If the fuse is open, test the ignition 1 and the tap up and tap down circuit for a short to ground.

⇒ If the fuse is OK, test the ignition 1 and the tap up and tap down signal circuit for an open or short to voltage.

Test the AT TAP shift switch for correct resistance value, 8.11-8.39 ohms.
⇒ If the resistance is not within specifications, replace the switch assembly.

⇒ If the resistance is within specifications, replace the control solenoid (w/body and TCM) valve assembly.
 

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Discussion Starter #16
I don't have a simple fix. It requires old fashioned analog troubleshooting:

P0826
Inspect the fuse in the ignition 1 voltage circuit for an open.
⇒ If the fuse is open, test the ignition 1 and the tap up and tap down circuit for a short to ground.

⇒ If the fuse is OK, test the ignition 1 and the tap up and tap down signal circuit for an open or short to voltage.

Test the AT TAP shift switch for correct resistance value, 8.11-8.39 ohms.
⇒ If the resistance is not within specifications, replace the switch assembly.

⇒ If the resistance is within specifications, replace the control solenoid (w/body and TCM) valve assembly.
I think we're at this point as the fuses are fine.

Test the AT TAP shift switch for correct resistance value, 8.11-8.39 ohms.
⇒ If the resistance is not within specifications, replace the switch assembly.

Can you recommend a place to test this that doesn't involve tearing open the entire center console? Maybe i can judiciously remove a panel or two?
 
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