MS3X/MS2 Trans Control on 4L60E

[2011grabbergt]

I just got done adapting a 4L60E behind a 1974 Dodge Challenger with a 408 stroke SBM. The MS3X controls the engine with sequential spark/fuel with LS truck coils (has been for a year or so and works great!), and I converted my old MS2 to control the transmission running 1.01 code. Mechanically, the trans works perfectly, which is a big relief since I built it and went through a fair amount of work to get it in a Mopar (still less work than adapting a late model Mopar trans sadly...)

All of my outputs work, and all gears and lockup do as well. It shifts great in test mode on jack stands. I caught the post about the flip flopped INJ outputs and fixed that already.

I cannot get the built in 40 tooth VR VSS sensor to read vehicle speed at all despite playing with the pots. I was wondering if the brave few who are also running this code on a 4L60E would know what the secret is before I spend a lot of time on it. Pull up resistor, polarity reversed, etc...

I'm also struggling with how the selector gauge and bottom gear position buttons are correlating what the pressure switches are saying. As far as I can tell, they are not working right and I am 100% certain that they are wired up correctly. The selector seems to change state to numbers that I have no idea what they mean, and the buttons for anything other than PRN1 do not work right.

Also, for the built in gear ratio selection for this trans, can someone confirm if the ratios are actually correct? I'm concerned because the grayed out fields are NOT correct and this trans should have a 3.06 1st, 1.63 2nd, 1.00 3rd, and a .70 4th. I'm assuming it has the right values and just doesn't update the grayed out fields, but would rather be sure.

MSQ attached, thanks in advance for the help!

[jsmcortina]

I'm also struggling with how the selector gauge and bottom gear position buttons are correlating what the pressure switches are saying. As far as I can tell, they are not working right and I am 100% certain that they are wired up correctly. The selector seems to change state to numbers that I have no idea what they mean, and the buttons for anything other than PRN1 do not work right.

You are testing while the engine is running aren't you? These use trans fluid pressure to work.

I'm assuming it has the right values and just doesn't update the grayed out fields, but would rather be sure.

Correct, the fields are for manual over-ride and don't reflect the built-in ratios.

James

[2011grabbergt]

Correct, I did this with the engine running. The bottom dash indicators didn't seem to correlate right, but the "selector" gauge does change. It's in numerical form though, so I have no idea if it is working right or not.

[jsmcortina]

Which numbers don't you understand.

Best to post a datalog.

James

[2011grabbergt]

Log attached. Here's what I observed in each gear and what the selector gauge displayed:

P/N - 0 on Selector
R - 0 on Selector
OD - (-1) on Selector
3 - 1 on Selector
1 AND 2 - 2 on Selector


Also, if my VSS leads are backwards, can I simply jumper the Inverted selection for the VRIN on the MS2 to correct that? Or do I have to repin my harness? It's the only thing I can see that may be causing my lack of VSS. It ohms out fine all the way back to the DB37.

[jsmcortina]

Looks like you aren't getting an input on the selector pos C input, it is stuck.

Measure the A, B, C inputs with a voltmeter with everything connected and in each gear. Check against the selector input truth table in the manual.

James

[2011grabbergt]

I just found a mispinned connector.... Apparently I was dyslexic when I pinned the female half of that connector. I don't know how I missed that.

Now I have:

P/N -0
R - 4
OD - -1
3 - 1
2 - 2
1 - 3

Does that sound correct? I tried flip flopping the VSS pins too, no go there so I have to do some more digging into why it won't read at all. Thanks again!

[jsmcortina]

Nope that's not correct.

You should get:
R = -1
P/N = 0
1 = 1
2 = 2
3 = 3
OD = 4

Check the the wires are in the correct order.

VSS wires flipped is unlikely to make any difference in this instance.

James

[2011grabbergt]

Will do. Engine OFF I got the expected pressure switch readings with a DVOM, but A and C could still be flip flopped and I'd get the same results, engine off, Park, or Neutral. I will switch them and give it a try. I don't have an easy way of measuring voltage with the engine running.

[2011grabbergt]

Got it all sorted out. A and C were mixed, and I found some assembly issues on the MS2 VR circuit after a few hours of pulling hair and going over every semiconductor with a meter and the schematics. I just took it out for a road test since we've had barely any snow (no salt) and it's still in the 50's here.

Everything works as it should! Thanks for all the help, this is absolutely incredible. It's eerie rumbling along at 55MPH and 1700RPM compared to how much faster this engine used to turn without an OD and lockup converter and 3.91's.

It'll sit for a few months until we get out of salt season, then I'll start testing and tuning the full combo. Excellent work on this code!

[Philip Lochner]

I cannot get the built in 40 tooth VR VSS sensor to read vehicle speed at all despite playing with the pots. I was wondering if the brave few who are also running this code on a 4L60E would know what the secret is before I spend a lot of time on it. Pull up resistor, polarity reversed, etc...

I also struggled to get a clean VSS signal. Ended up feeding the VSS output from the 4L60 to a TP500 ignition module and then fed the square wave output from the TP500 to the TCM (now modified for square wave input). See: http://www.msextra.com/forums/viewtopic ... a9#p447803