Tci Tcu Questions

[MRKING]

Im taking my truck down to miami the end of jan . While the tranny does move the truck , when I look at the tci dashboard it looks like something doesnt add up . At idle my tcc line pressure shows 80.0 , line pressure shows 3.5 (reading the help section of the tci program , it lists line and tcc pressure as 0-max 100-min) and the actual gear always reads 1st (no matter where the shifter is at). Also tps is 100% at idle. When I installed the trans , I did diagnostics per instructions from the tci manual on all the electronics and solenoids. All were easily within the ranges listed and I double checked all the wires to the tcu during install .

I do have reverse and have had it up to 40 on the back roads (no tags yet) ,but it is a dog. I dont want to push it any further until i can verify all is well .

Can anyone post a screenshot of what their tci dashboard looks like at idle ??

 

[MRKING]

Re: Tci idle screenshot

Re: Tci idle screenshot

Ive been looking through some 80e technicians guides and found something that sounds like what I am experiencing .

"If for any reason the entire electronic control system of the transmission becomes disabled , both of the shift solenoids will be de-energized .This "failsafe mode" operating state of the solenoids forces the transmission to operate in second gear regardless of other vehicle operating conditions when the gear selector is in the forward drive range . Also , in " failsafe mode" the force motor is turned off which increases line pressure to a maximum and the PWM solenoid cannot apply the TCC ."

I am going to pull my seat and go over all the tcu wiring and see whats up . It connects to my laptop syncs right up and shows rpm data so I dont know ?

I know only a handfull of you use this product on the limited 4l80e equipped syty's out there , but i really could use some base info from you guys to see if what I have is common at least .TIA .

 

[sly dvl]

Re: Tci idle screenshot

Re: Tci idle screenshot

So can you get manual first?
I had a similar condition on my '97 S10 (4L60E) and the problem was the ign. switch. One feed off the switch was for the trans. and with no power on that circuit I had nothing but 3rd, manual second, no 1st, no O/D & no TCC lock up, plus a really harsh engagement because ofthe increased line pressure (by default). All that from one wire...

K

 

[JSM]

Re: Tci idle screenshot

Re: Tci idle screenshot

Yes the 80e will default to 2nd, Jeremy and I did a lot of testing trying to get the stock ECM to work in this mode.

The rpm signal for the TCI comes through other wires, not the plug on the trans.

If you load the screen up, does the TCI show what gear is selected? I can't remember the exact TCI screens but it should so gear selected as you move the shifter. Sounds like you have a plug issue on tranny side of things, bad connector, something.

 

[MRKING]

Re: Tci idle screenshot

Re: Tci idle screenshot

Yeah jeff I have to agree with you . After pulling my seat and checking the power wires , next step is to jack her up and check out underneith . It doesnt show any different gears whether im in forward or reverse.

Im kinda bummed out , I wish it would go easy for once ...

 

[MRKING]

Re: Tci idle screenshot

Re: Tci idle screenshot

Well after tracing wires and testing everything , I found I am getting power to both sides of the trans connector plug . The troubleshooting for the solenoids taken at the end of the cable inside the truck @ the tcu is :
Shift solenoid A 21.6 ohms (20-30 range acceptable in manual)
Shift solenoid B 21.5 ohms (20-30)
TCC PWM solenoid 11.9 ohms (10-15)
Force motor 3.9 ohms (3.5-8)

I also double checked the Tiss and Toss sensors .So now knowing the plug is making a good connection to the trans and all the parts are connected and in working order , I am open to ideas on what to do next . If any of the tranny builders on our forum threw out ideas , it would be much appreciated .

 

[MRKING]

Re: Tci idle screenshot

Re: Tci idle screenshot

I had a little syclone time earlier and finally got my laptop to do screenshots . First thing I noticed was the high voltage . According to my astg manual , on a stock 4l80e tcu , any voltage over 19.5 volts for more than 2 seconds sets a code 53 (system voltage high) that results in maximum line pressure , 2nd gear only , and inhibits tcc operation . I dont know if the tci unit has the same codes and defaults but I am sending my box back to tci for testing .

This is at idle in park , usually rpm isnt at 1000 , but i had just started up it up . Tps at 100% isnt correct either . :dunno:

 

[MRKING]

Re: Tci idle screenshot

Re: Tci idle screenshot

Just got my unit back from TCI . According to the tech guy (Brad) ,the unit was fubar and was replaced with a new *tested* unit .
Plugged it in and selected the 6cyl 4l80e mode , right away I saw good things on the dash . Voltage now displays 13.5 vs. the previous 27.4 and Tps at idle reads 15% vs. the always 100% before .

That was the good news .

Bad news is the truck feels the same as stated above when I attempt to drive it . It moves forwards & backwards , but clearly there is still a problem . The gear selector on the dash will switch readings from 1 to 2 when I move the shifter , but park is 1 , reverse reads 1 , and everything else reads 2 . :squint:

Does everyone elses actually display PRN1234 on the laptop dash ??

My trans did always have a single drip per 10 minutes of run time , now I am going to kill 2 birds with 1 stone and pull that biatch . Im going to see why the electronics inside arent working and seal my JSM adapter a little better this time , didnt use enough last time I imagine .

Any advice on what to look for OR at . Until I can completely rule out the trans , Im not certain the tci unit isnt still the culprit . Fun Fun :tup:

 

[JSM]

Re: Tci Tcu Questions

When the TCI works it seems to work well. I have seen more failures than I like though. You have had 1 already, local guy just found out his was bad, and I know several others have also. Makes it flusterating for sure when your trying to troubleshoot a new install and not sure if it is hardware or install.

 

[maty111]

Re: Tci Tcu Questions

yea mike that sucks. im sure glad there's no electronics in my tranny

matt

 

[George Blake]

Re: Tci Tcu Questions

The manifold pressure switch is what tells the controller what gear you are in. If something is wrong with the manifold (cut o-ring, unplugged, etc), it won't feed the data. Did you bench test the manifold switch assembly for installing it? If you cleaned it with solvent and used air pressure to dry it, it will damage it. TCI no longer distributes the older style. They keep a few units for warranty purposes but that is it. The only thing available now is the PCS style TCI setup that is 4L80e/4l60e specific.
Park and neutral will both show "neutral", everything else will still show gear. The pcs style is nice because you get a full dashboard. Much easier to read.
Provided the manual shaft is in correctly and the shift kit was installed correctly, the manifold assembly will be the only issue left to trouble shoot. You just need an ohm meter to check it.
Is your TPS showing correctly now? I've seen people hook the wires up backwards causing it to flip flop the TPS reading.
Now it's clear why a dyno session is so important.
Just noticed, that ignition voltage is crazy also....24+ volts?
Edit: read your other post better, looks like everything else is fixed except for the controller not know what gear you are in.
The transgo kit has that black plate. You need to make sure everything is torqued on that sucker because the manifold seals on it. If it leaks, your result will be what you see.

 

[MRKING]

Re: Tci Tcu Questions

Thanks for the tips George . I will be sure to check those items before taking it to the shop for dyno testing . The unit they sent back was still my original case , but the mixmatched loose screws tells me they at least opened it up and swapped in different parts .

Im grateful they only charged me return shipping , lets hope theres not a reason for the nice gesture . If for some reason it still is the problem , stock controller here I come .

 

[MRKING]

Re: Tci Tcu Questions

I just jacked it up , drained all the fluid (glad I put in a drain plug) and didnt see any loose connectors .As careful as I was with all the fluid so far , the darn filter was holding more fluid above it than I thought , oops !!
I unplugged and replugged in the psm and am letting the last of the fluid drip dry as I type . When I go back out and ground the specific wires , do I need to move the gear range selector to view what it says on the tci dash ? I can just ground a wire , check what gear its in and continue ?

 

[MRKING]

Re: Tci Tcu Questions

eesh !
Dont feel bad :lol: , I did pull the pan to verify everything was connected and that the manifold was properly torqued down . The only question I have is about the force motor wiring . The non-oem force motor I installed was per instructions but looking at it now , is the green supposed to go to green ? I cant find the instructions to it anymore from the install I did 1.5 years ago .

Yeah it would have been easy to check the tci side of the plug , but how else am I supposed to learn . After the force motor concern , I am going to install the pan again and fill 'er up .So power on , tcu unplugged , ground soleniods and then the only way to determine gears is by feel .

The tci troubleshooting page shows jumpering connector pins Y2+L3 for shift solenoid "A" and Y3+L3 for shift solenoid "B" . L3 is labled as the 12v power lead , so knowing that I imagine the wires to ground are Y2 for the 1-2 and Y3 for the 3-4 . I do appreciate everyones help and I dont regret learning this the hard way , but Im deffinately not opening up my own trans shop . :rotf:

 

[George Blake]

Re: Tci Tcu Questions

It may be an illusion but is the little bracket that holds the force motor in actually keeping it in place? It looks flipped in the picture.

You guys are correct. The force motor is not polarity sensitive.

 

[MRKING]

Re: Tci Tcu Questions

I got some syclone time while my 3 year old is sleeping just now . After looking through my tranny manuals for a couple days , I think this same test should still work *in theory as to rule out the trans or the tcu* without fluid and still under the car . I tested this and heres what I found .

With the trans plugged in to the tci unit and key on , I verified power to the trans at the plug and inside the trans plug side. Each of the 3 wires on the psm at rest shows power .

I ground wire A (red wire) hear nothing , but Tci dash displays 1st gear
I ground wire B (black wire) hear a small buzz and again Tci dash displays 1st gear
I ground wire C (orange wire) again hear buzz and same Tci dash displays 1st gear

With the controller unplugged , everything still has power , including the Y2 & Y3 wires on the controller plug side . When I ground them each or together , I hear nothing . When I had the truck running on this new tcu , just before draining the fluid last week , it was showing 1st indicating that the correct wires were getting grounded through the electrical circuit but it didnt feel like 1st gear .

From the test that dave suggested , as long as the 1st gear solenoid was grounded , regardless of the presence of a controller or not , it should be in and feel like first gear if the trans was in working order ?? It does not respond accordingly , so i feel at this point the controller can be ruled out as the problem .
.
.
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Is it safe to say the MANIFOLD is bad and NOT the controller ?

 

[George Blake]

Re: Tci Tcu Questions

I'm gonna scan the procedure for checking your manifold. It'll take about 20 minutes to check it. It will have to be removed to check it though. You'll need an ohm meter and two pencils. You'll need to use the eraser end of the pencils to push on the appropriate discs while taking ohm readings.

You are only gonna display first gear because the manifold is not giving any feedback. You MUST move the hydraulic manual shift valve to allow fluid, under pressure, to get to the correct spots on that manifold.

We were talking about grounding SOLENOIDS. The shift solenoids. Not the manifold. Grounding the wires leading to the manifold will possibly do damage because you are sending the reference voltage straight to ground. Dead short.
Don't get frustrated. You'll get this.

I got some syclone time while my 3 year old is sleeping just now . After looking through my tranny manuals for a couple days , I think this same test should still work *in theory as to rule out the trans or the tcu* without fluid and still under the car . I tested this and heres what I found .

With the trans plugged in to the tci unit and key on , I verified power to the trans at the plug and inside the trans plug side. Each of the 3 wires on the psm at rest shows power .

I ground wire A (red wire) hear nothing , but Tci dash displays 1st gear
I ground wire B (black wire) hear a small buzz and again Tci dash displays 1st gear
I ground wire C (orange wire) again hear buzz and same Tci dash displays 1st gear

With the controller unplugged , everything still has power , including the Y2 & Y3 wires on the controller plug side . When I ground them each or together , I hear nothing . When I had the truck running on this new tcu , just before draining the fluid last week , it was showing 1st indicating that the correct wires were getting grounded through the electrical circuit but it didnt feel like 1st gear .

From the test that dave suggested , as long as the 1st gear solenoid was grounded , regardless of the presence of a controller or not , it should be in and feel like first gear if the trans was in working order ?? It does not respond accordingly , so i feel at this point the controller can be ruled out as the problem .
.
.
.
Is it safe to say the MANIFOLD is bad and NOT the controller ?

 

[George Blake]

Re: Tci Tcu Questions

http://www.not2fast.com/megashift/trans_data/GM_4L80E.xls

That page has a ton of data but not how to check the manifold directly on the bench. I'm still looking.

 

[MRKING]

Re: Tci Tcu Questions

I really do appreciate both of you helping me with this . I stopped getting frustrated with my sy a while ago . I find it never really helps anyway .

Ive had this truck for about 4 years now . Since ive never really driven it anywhere , i really dont mind this keeping me from starting to . I know my time will come one day . I never did have intentions of any kind of regular driving with it , but I sure didnt think the miles would stay this low . LOL !!
Its kinda like the ty I recently picked up off renz . Will it get driven much ? Probably not , I guess I just like projects to work on when time permits or whenever the ole' lady is buggin .

I know in the end once there complete, it will have all been worth it . Thanks again .

 

[MRKING]

Re: Tci Tcu Questions

Hey dave glad to hear your motor sounds like a easy fix , take that whenever you can , it doesnt come often.

Each of the wires inside my trans does show 12v+ when the key is on . I kept saying 1st to signify that the controller was picking up me grounding each of them when i was simulating a gear change. On the old tcu that I sent back , it wouldnt display any gear but 2nd .A week ago I really thought the new controller was still the culprit , so I wanted to make sure it was showing what I was doing . Ive been trying not to leave out any info that I may overlook and think nothing of , but someone knowledgeable would pick right up on . Sounds like we (you guys) have it narrowed down .
Its not that I didnt believe the little tag that Brad @ TCI stuck on my tcu that reads *tested 1-20-08* , I guess I had to make sure myself . :lol: Sure glad I didnt fill the trans back up .