4l80e problem symptoms

[erasedhammer]

erasedhammer, wave sizes, shapes, and voltages are around step 372. You haven't confirmed step 1. To answer as asked though, the voltage and frequency will vary with wheel speed. The shape will be roughly a square wave _]-[_]-[_ (the dashes belong at the top of the brackets, don't have a fancy keyboard right now).

Yeah I may be getting ahead of myself, my vehicle is down at the transmission shop right now so I'm just planning it all out for when I stop by tomorrow.
As the for ESS, like the TPS is usually has a range of voltage for idle and various speeds. I thought I saw info on that somewhere, but can't find it now. Most just need proper voltage output at idle to confirm the sensor is working.

 

[someoldmoose]

Any of the "SS" s only show voltage to the computer when whatever they are pointed at is turning (magnetic Hall effect sensor). If you mean the input voltage going to other sensors, I believe it's 5vDC, kinda a standard reference voltage for sensors. The output wave sign is what the computer bases it's "decisions" from. In a TPS, the sensor varies the reference voltage with a potentiometer. Hall effect sensors have no reference voltage as the voltage is induced by the teeth passing through the magnetic field lines. (Sorry for the Bill Nye description, but I love that guy). Use a volt ohm meter with 10 megaohm (mOHM) resistance to check electronic circuits. If you wanna see the wave picture it'll cost ya. A cheap graphing multi-meter is expensive. Might find one on the internet somewhere. Mine was over $500 when I bought it 15 years ago. Unnecessary unless you work on these kinds of circuits every day, but definitely very cool to see stuff working, or not.

BTW - 86humv was nice enough to correct me on your other thread ( I freely admit when I am wrong ) Here is the right answer to your original inquiry in the other thread :

CZSU Is for a 01 6.5 NA truck
16196390 is just a standard 12v trans computer.
There is another brand computer used in these trucks...PCS Tcm2100ba

That being said, from what I gather, your tranny is an '03 and the box the chip was in identifies it as an '01 chip ( thank you again 86humv) so somewhere in this mess ( I saw you mentioned eBay sellers) you seem to have a mismatch. Get "everyone" speaking the same language and I suspect the communications will flow like mud off a Hummer's bumper in the swamp.

 

[erasedhammer]

Got the 4l80 to shift! turns out the STE/ICE pos connector wasn't actually connected. Don't know how I missed that but now the tranny works. Only problem is its throwing code 22, low TPS voltage.

current symptoms are radically different shifting points:
1-2 happens at 2000 rpm
2-3 happens shortly after
3-4 happens at 35 mph

Although it is nice having a quiet humvee at those low speeds, it just seems like it should be higher. TPS poorly adjusted?

 

[Waters]

This thread went quiet a year ago! I'm finally getting serious about my conversion parts list and noticed that a trusted seller has a good price on a PCS TCM-2100BA (he says its for a M1113, I have a 94 M998A1 with GEP 6.5NA). If there really are differently programmed versions of TCMs out there for humvees, that could make this a bit more complicated.

I'm curious how your conversion has worked out, Erasedhammer. I notice you went with the 6.5TD swap too, I may want to pick your brain a bit as I haven't gotten around to grabbing the 4l80e yet and there are still some pull out complete Turbo drivetrains out there. I kinda wonder if installing the whole new drivetrain with the sensors already installed would be more worth it than retrofitting a 6.5NA with TH400 to a 4l80e, and then you also get to have that coveted extra HP!

 

[erasedhammer]

This thread went quiet a year ago! I'm finally getting serious about my conversion parts list and noticed that a trusted seller has a good price on a PCS TCM-2100BA (he says its for a M1113, I have a 94 M998A1 with GEP 6.5NA). If there really are differently programmed versions of TCMs out there for humvees, that could make this a bit more complicated.

I'm curious how your conversion has worked out, Erasedhammer. I notice you went with the 6.5TD swap too, I may want to pick your brain a bit as I haven't gotten around to grabbing the 4l80e yet and there are still some pull out complete Turbo drivetrains out there. I kinda wonder if installing the whole new drivetrain with the sensors already installed would be more worth it than retrofitting a 6.5NA with TH400 to a 4l80e, and then you also get to have that coveted extra HP!

That TCM is the newer generation one with some extra features to protect the transmission. Not sure the compatibility, but should be fine as long as it's the same connector on the outside of the box.
The PROM for the shift points will be a little different since that one will have it set up for a turbo. It will still work but the shift points will be different since you have a lower hp/tq engine.
For that TCM I believe it does have a swappaes PROM, but those are 200+ for a small chip with different vehicle data loaded on it, not worth it imo.

For example when I had my 6.2 and 4l80 with the PROM from a 6.5 turbo, I'd go to accelerate and I would have to let off the pedal for a second to get the transmission to shift into the next gear. Kinda annoying, but also felt more involved (in a good way). Then I changed to the turbo motor and the shift points were right on par, as long as the TPS is adjusted correctly.

As for a whole drivetrain swap or just leaving your 6.5, it all depends on your use. If all you do is occasionally driving on the road and off roading driving then I'd say leave the 6.5NA in with the 4l80 (the 6.5 na is a lot easier to mate to a 4l80 than a 6.2 is).

Now if you do a ton of highway driving I would definitely suggest going to the turbo and 4l80 drive train. Plus if you don't mind a little more money, swap your diffs for a lower 2.56 ratio. Stock tires and I hit 60 at 2100rpm. I had 2.73 diffs before and 60 was more at 2400rpm. On paper not a big difference, but in reality it's a big notice in noise and mpg.

 

[Waters]

thanks! i suspected all TCMs were not equal but hadnt been able to get a straight answer.

most of my driving is unfortunately on 55mph highways, so being able to do and keep 60 mph would be great. if i could do 65, id feel like i could hop around via the interstate. anything on top of that is beyond my wildest dreams.

not to hijack the thread any further, but what resources did you use to do the turbo swap?

 

[erasedhammer]

thanks! i suspected all TCMs were not equal but hadnt been able to get a straight answer.

most of my driving is unfortunately on 55mph highways, so being able to do and keep 60 mph would be great. if i could do 65, id feel like i could hop around via the interstate. anything on top of that is beyond my wildest dreams.

not to hijack the thread any further, but what resources did you use to do the turbo swap?

With the turbo engine and 2.56 gears 55 is right in the power curve and is nice to cruise at. Going 55 with your current setup would be equivalent to doing 75 in my setup, bit difference.

For just the engine part of the swap I had a 2 ton engine hoist, my floor jack, and a box of wrenches. Hardest part is getting the engine out and the new one back in, I would suggest more like a small crane to make it really easy and a lift. For the turbo you need at the very least a 1/2 body lift. Super easy to do, I did it with a floor jack.

 

[dhaumann69166]

If it won’t go past second gear how are you getting it to downshift from third to second at high speed? My M1038 is always in 3rd above 30mph and usually if you don’t shift manually you don’t notice first to second gear shift cause it usually happens around 5 mph if you aren’t hard on the gas. Second to third usually shifts around 18 to 20 mph. Over 30mph and you are going to be making that 6.2 scream in second.

 

[erasedhammer]

If it won’t go past second gear how are you getting it to downshift from third to second at high speed? My M1038 is always in 3rd above 30mph and usually if you don’t shift manually you don’t notice first to second gear shift cause it usually happens around 5 mph if you aren’t hard on the gas. Second to third usually shifts around 18 to 20 mph. Over 30mph and you are going to be making that 6.2 scream in second.

Sorry post is way old. It turned out was just high shift points. Adjusted the tcm, got a 6.5turbo engine all is fine