EFILive 7.5 will open the T87 tune. For some reason I wasn't expecting it to work, but it did. I think the CAX8 is for v8, and CAX is for 7.5, so an existing CAX file 'should' still be fine in 7.5.Yeah that’s still not going anywhere. I tried converting the cax to a cax8 and made no difference. I’m wondering if something is off in the cax file for the newer updates because I’ve seen where guys have tried to convert a cax to a cax8 and it would not populate in v8. They had to go back in and adjust some code to make it work. I may have to sift through that’s whole cax file and see if everything is as the template says it should be
T87 Swaps
- Thread starter kidturbo
- Start date
. I tried converting the cax to a cax8 and made no difference. I’m wondering if something is off in the cax file for the newer updates because I’ve seen where guys have tried to convert a cax to a cax8 and it would not populate in v8. They had to go back in and adjust some code to make it work. I may have to sift through that’s whole cax file and see if everything is as the template says it should be
Text/email me your address and I'll get it sent out. I believe it is a good module.
@Cougar281 have you a VR condition ready to go play. I soldered the jumper on PCB so it receives power from the T87 9v Ref, and only requires an extra ground wire, along with our 4 sensor wires going in and out. Reran all the pattern tests, and TCM seems just as happy with this data. The TOS/VSS out signal looks usable on the bench. So you verify how the other nodes respond to that.
Mounted it in my favorite IP67 case with a clear lid so you can show off your wiring skills..
Actually the same lid I use on all the CANbus gateways because it allows ya to see the power LED, and tell if any moisture gets into the case. But for now, they are handy and fits the bill. Once we verify this conditioner works, I'll load up a file and send ya the matching dual CANbus ARM M4 gateway top half. Unless you prefer Ardunino, then a teensy should fit in there too...
Mounted it in my favorite IP67 case with a clear lid so you can show off your wiring skills..
Actually the same lid I use on all the CANbus gateways because it allows ya to see the power LED, and tell if any moisture gets into the case. But for now, they are handy and fits the bill. Once we verify this conditioner works, I'll load up a file and send ya the matching dual CANbus ARM M4 gateway top half. Unless you prefer Ardunino, then a teensy should fit in there too...Nice! Can the CAN gateway take discrete inputs (tap shift) and spit out CAN data, and take CAN messages (PRNDL, tap shift display) and spit them out on Class2? Or is it meant just for massaging the CAN messages that are different between the years?
The current gateway only does CAN-2-CAN traffic. But have a single channel version with ADC chip also.
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I'm not even sure you guys are speaking english but that sure is pretty....lol
It basically sticks or stuffs a round peg in a square hole.. And the square hole likes it...
I've been using HPT for the gasser versions. But haven't tested it with any Allison versions yet. All the DTC's and such are mapped pretty good, but it's harder to work, with and doesn't load all segments. So when dealing with custom bins, I'd prefer using EFI.. Since I have the map data, really need to build a CAX to turn off a few things in the T87.So this is interesting... Apparently the latest FILive Beta version added support for editing the T87A OS 24285377... Which happens to be the one that the Allison T87A Calibration uses...
Who wants a V8 CAX project?
Your using NEMA/J1939 connectors? I’m guessing your just making a conversion cable of some sort? Or are those data access points?
Exactly, only 4 wires required for testing out data however. 12v +/- and CAN hi/lo. N2k cabling has a shielding, but of no concern for this one.
Have existing N2k hardware that's already IP67 encased, has dual Opto-Isolated CAN channels [2x M12-5 connetors}, and a proven track record in the field. While the plan is to just emulate everthing using just 1 CAN channel, on the gasser side, I'm doing a gateway vesion for stand alone with Non-GM hardware. So same tool, both jobs. 3 if you count N2k converter for boats.. lol
That case I've been using forever, and just so happened to have a little extra unsused space, with mouts for a PCB. So the VR conditioner fits in the existing gateway cases. Once it's all sorted and ready to run 100pcs, I can merge units onto 1 board wtih single connector specifically for the Allison stuff. At least that is the plan..
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Well, that was a semi-success.... When I first fired it up, had a P077C that was supposedly current and for some reason, the transmission refused to go into any gear. Cleared the codes and it would go into gear and all seemed pretty good. It shifted, but then the speedometer got erratic and ABS was totally ticked off. I actually was able to go for a short drive and it shifted all the way to 5th, but then when I turned around to come back, it wouldn't shift out of 1st, and when I checked for codes, I had P077D and P07C0. I've also started getting a P0880, which I haven't seen before.
Attached is an EFILive log I took - it seems the TOS is... Erratic.... Apparently, my truck can go from 16MPH to 158MPH in the blink of an eye
Attached is an EFILive log I took - it seems the TOS is... Erratic.... Apparently, my truck can go from 16MPH to 158MPH in the blink of an eye
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Well it shifted gears, that's progress in my book.Well, that was a semi-success.... When I first fired it up, had a P077C that was supposedly current and for some reason, the transmission refused to go into any gear. Cleared the codes and it would go into gear and all seemed pretty good. It shifted, but then the speedometer got erratic and ABS was totally ticked off. I actually was able to go for a short drive and it shifted all the way to 5th, but then when I turned around to come back, it wouldn't shift out of 1st, and when I checked for codes, I had P077D and P07C0. I've also started getting a P0880, which I haven't seen before.
Attached is an EFILive log I took - it seems the TOS is... Erratic.... Apparently, my truck can go from 16MPH to 158MPH in the blink of an eye
I replayed the logs a few times, and the turbine and output shaft speeds looks pretty solid. Didn't notice any jumps or drops, so guessing it's TOS jumping around is noise related. The 5v patterns looked good on bench, so would like to compare on a truck if ya can scope it. There is a 220ohm pull down resistor in that circuit, as the other two output lines. You can remove and see how it acts. I haven't tested these boards wihout, but thinking we start there.
Also we can try powering the board with 12v rather than robing power from the TCM ref line. I tested for a good bit with 12v power, and against theE38, but not sure how that TOS line signal looks with other nodes involved. I'll send ya a pic of jumper to de-solder, and then we can power it off that extra terminal and see how reacts.
Let me know if you have any analog scope handy, and bet we can sort it out pretty quickly. Other codes, I think we can adjust with those pots.
Well it shifted gears, that's progress in my book.
I replayed the logs a few times, and the turbine and output shaft speeds looks pretty solid. Didn't notice any jumps or drops, so guessing it's TOS jumping around is noise related. The 5v patterns looked good on bench, so would like to compare on a truck if ya can scope it. There is a 220ohm pull down resistor in that circuit, as the other two output lines. You can remove and see how it acts. I haven't tested these boards wihout, but thinking we start there.
Also we can try powering the board with 12v rather than robing power from the TCM ref line. I tested for a good bit with 12v power, and against theE38, but not sure how that TOS line signal looks with other nodes involved. I'll send ya a pic of jumper to de-solder, and then we can power it off that extra terminal and see how reacts.
Let me know if you have any analog scope handy, and bet we can sort it out pretty quickly. Other codes, I think we can adjust with those pots.
I have a picoscope, so we should be able to get a look at it. Probably won't be able to do much until tomorrow or the weekend though.
Welp... I have some info... maybe.... I scoped the VSS and Turbine outputs 'just because', and then I scoped the TOS output. While I was scoping the VSS/Turbine outputs, the speedometer flaked out every time it got over 20 MPH or so I believe. But when I was scoping the TOS output, it WOULD NOT flake out. Not once. Disconnect the scope and if flaked every time. Not sure if that says anything.
Also, as I expected, the T87 & T87A both functioned pretty much identically in stock form.
Also, as I expected, the T87 & T87A both functioned pretty much identically in stock form.
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Ok we're on the right path.. Just keep your scope connected, and loggg more data ...
If it's voltage level, lets add a little more resistor in the TOS line and see how acts.
If it's voltage level, lets add a little more resistor in the TOS line and see how acts.
Loaded up the latest pico software, along with your log files. Think I found our TOS issue.
Don't recall the A50 output being -4v to +4v peak to peak pattern, but that scope typically doesn't lie. Then a blind squirrel could spot our main problem pretty easily.
A50
VR Conditioner
I tested the E35B against a 0-5v square wave, and it was a happy camper. So I bet if we can square that up a bit, and lower the floor to zero at least, probably be a happy camper for now.. At least the turbine and vss signals to the T87 are close enough to keep it happy. We can fine tune on those with just a volt meter to check the floor value at Key On. Currently it should read about 1.5v, and suggest ya bring that down to around 1v on both lines using the POTs. See if that stops it setting the other related codes.
It's happy enough to shift gears, so that's one huge hurdle behind us...
Don't recall the A50 output being -4v to +4v peak to peak pattern, but that scope typically doesn't lie. Then a blind squirrel could spot our main problem pretty easily.
A50
VR Conditioner
I tested the E35B against a 0-5v square wave, and it was a happy camper. So I bet if we can square that up a bit, and lower the floor to zero at least, probably be a happy camper for now.. At least the turbine and vss signals to the T87 are close enough to keep it happy. We can fine tune on those with just a volt meter to check the floor value at Key On. Currently it should read about 1.5v, and suggest ya bring that down to around 1v on both lines using the POTs. See if that stops it setting the other related codes.
It's happy enough to shift gears, so that's one huge hurdle behind us...
So you're saying the output needs to be treated as -5v to +5v instead of -4 to 4? Also, what is that little "skip" at t he end of each wave on the VR picture?
I honestly dont know.
I honestly dont know.
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That a neat setup. I’ll have to keep you in mind on my next project.