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Discussion Starter · #1 ·
Just had the codes pulled from a real code reader, I'm happier than you would probably think.
here goes
0501 - vss out of range
0722 - vss not working
0741 - tcc issue
0742 - torque converter not locking up
0751 - shift solonoid (front)
0756 - shift solenoid (back)
0758 - shift solenoid 2-3
1870 - tcc
1871 - ecm doesnt know what gear to be in
1875 - 4wd low switch circuit (I have a 2wd).


Soooooooo
Anyone know where the transmission / computer get their grounds from? I am certain I have a ground issue, a massive one. I have fss circuit issues, IAT circuit issues, a massive number of issues. Either a rat chewed wires, or there is a massive ground issue.

TIA
 

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Discussion Starter · #3 ·
The grounds thread link can be found over in the 6.5L FAQ page: Grounds-Grounds-Grounds The importance of good grounds.....
(y)
thank you
You’ve sent me that before
Is there a specific location the transmission picks up a ground?
I have 2 ground straps to the block, 2 to the firewall, and tomorrow I am going to add 1 to the frame.

people speak about a ground location on the back side of the engine, passenger side.
I felt behind the head and there is nothing there.

Do we know where the pigtail goes from the transmission? Does it have a plug somewhere before the ECM or does it go straight to the EXM?

I am unsure if you remember but all my solenoids and sensors test good with the resistance test so I obviously have a wiring issue.

Thank you again
 

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thank you
You’ve sent me that before
Is there a specific location the transmission picks up a ground?
I have 2 ground straps to the block, 2 to the firewall, and tomorrow I am going to add 1 to the frame.

people speak about a ground location on the back side of the engine, passenger side.
I felt behind the head and there is nothing there.

Do we know where the pigtail goes from the transmission? Does it have a plug somewhere before the ECM or does it go straight to the EXM?

I am unsure if you remember but all my solenoids and sensors test good with the resistance test so I obviously have a wiring issue.

Thank you again
Post #11 from Turbine Doc in that link has a picture pointing out those grounds on the passenger side of the engine.
 
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See Post #7
 

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Discussion Starter · #6 ·
Post #11 from Turbine Doc in that link has a picture pointing out those grounds on the passenger side of the engine.
See Post #7
ya
I was just trying to find that

so y’all know
I ran a ground from battery to rear ground station on top passenger side rear.

that post also refers to a ground station by turbo support. I do not think the 1996 has that
 

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They are auxiliary 12v. high amperage sources for whatever add-ons need it.
 
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Discussion Starter · #11 ·
Product Wood Electrical wiring Office equipment Tints and shades
Computer is out
Does anyone know the 2 wires that go to the brake switch? 1 is 12v with pedal not pressed
One is 12v with pedal pressed

does anyone know which wires go to transmission?

I’ll be researching this myself too, just thought Id ask
 

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24 pin brown conn.
B9 - PPL - NC - 12v. ign
B10 - WHT - NO - 12v. batt
 

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Discussion Starter · #14 ·
Update.
There are more codes than listed above, one of which is no gear ratio selected. In other words the computer is not reading the vssb. My speedo is also 150% faster than what I am doing, and the odometer rolls just as fast.

While I was under the dash looking at the brake switch wiring, I noticed there is a rod which attaches to the shift cable. The shifter you put your hand on goes into the plastic housing, down, and then it attaches to a cable, and a rod. The cable goes to the transmission. The rod goes to an electronic thing. Mine has a bright blue / white stripe wire. I use the word bright indicating it is new. This rod was disconnected and zip tied to a bracket. I reconnected it and the gas pedal feels a lot better. Still no OD, still to TC lockup, and the speedo is still 150% faster. But I will definitely say tthe gas pedal feels better.

I tried to follow the brake switch wires. It is very tight in there and I cannot even see, but I believe they go into the big loom, which goes into the engine bay. There is a circuit board on the loom, which I am unfamiliar with that it does. There is also 2 distribution blocks down there, but seem ok. 1 has relays on it, and I need to make sure I have all the relays in, and they are working correctly.

In the broader scheme of things.
The computer is not reading the vssb, and the vssb is right next to it. I cannot follow the wires because it is so tight in there, I am starting to think it is all related. I have 2 vssbs. I have 1 set to a 4.10 gear ratio, and the other set to a 4.54 gear ratio. They both do the exact same thing when plugged in. I am convinced the computer is not reading the vssb.

Anyone have ideas how that is even possible? Do the wires from the vssb go some where before the computer? It seems like there should just be a few short wires that just go into the computer, but they don't, they go into dash never never land, never to be seen again. So I gotta hunt them down.

Thanks y'all.

And if I figure this out I promise I'll post the solution
 

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The only thing the VSSB tells the PCM, and the ABS, and the speedometer
and even the radio, is what the output speed of the VSS sensor is.
The switch manifold in the tranny tells the PCM which gear has been detected.
The manual shift shaft tells the tranny which gear you are requesting.
The park/neutral switch on the side of the tranny tells the gauge cluster which gear the shifter in in.
 
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Discussion Starter · #16 ·
The only thing the VSSB tells the PCM, and the ABS, and the speedometer
and even the radio, is what the output speed of the VSS sensor is.
The switch manifold in the tranny tells the PCM which gear has been detected.
The manual shift shaft tells the tranny which gear you are requesting.
The park/neutral switch on the side of the tranny tells the gauge cluster which gear the shifter in in.
After a little searching on FB
Im thinking its the ignition switch
Aupposedly the transmission is wired through it
 

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The TRANS fuse feeds the tranny internals. It also powers the gear indicator on the gauge cluster.
It is a separate output of the ign. sw. with nothing else on that circuit so it can be a problem.
Check your TRANS fuse for 12v. with key on.
 
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Discussion Starter · #18 ·
The TRANS fuse feeds the tranny internals. It also powers the gear indicator on the gauge cluster.
It is a separate output of the ign. sw. with nothing else on that circuit so it can be a problem.
Check your TRANS fuse for 12v. with key on.
Ya
I did
I think its position 18
I’ll double check it again.
Based on what FB is saying ignition switch is my problem
 

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Ya
I did
I think its position 18
I’ll double check it again.
Based on what FB is saying ignition switch is my problem
Be careful with the advice from FB.. You can get some wrong advice and end up causing more damage .
There are some true knuckleheads on FB
 
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