4l80e pcs or general solenoid Q

bezerk

New member
as some as you migth know. i got quickstop his pos truck
today i spent some time working on the 4l80e. stuck in third or second.
anyway. if i measure up the wires going to the tranny. pinkred and pinkblack, solenoid 1 and 2. do they get a 12v power when they are powered, or is it grounded.
right now i have a 12v+ power on the pinkred i think. when selected drive.
i tried to have it shifitng. but ofcourse the clamp popped off the turbo.

thanks for your help
 

Quickstop [UK]

Combating adversyty.
Re: 4l80e pcs or general solenoid Q

The computer has the pcs instruction manual on it in My Documents-> trans or pcs I think....
 

DaveP

Active member
Re: 4l80e pcs or general solenoid Q

The wire colors you mention are different than the diagrams I have.

The solenoids should have 12V to one terminal at all times. Grounding the other terminal energizes the solenoid.

No power to the trans will result in 2nd gear-only operation.

I can't find the combination for the solenoids vs what gear for the 80e. But with the wheels in the air, engine running, grounding the solenoids in combos of off/on, off/off (2nd) on/off, and on/on should give you all (4) forward gears.
 

bezerk

New member
Re: 4l80e pcs or general solenoid Q

The computer has the pcs instruction manual on it in My Documents-> trans or pcs I think....
couldn't find them, not in that folder. mail them too me.

davep

the pink black one is for solenoid a.
pink red one solenoid b
i stripped the wires, and measured voltage on the wire for solenoid a while putting it in to drive. just wondering if that is a good thing or bad thing.
 

bezerk

New member
Re: 4l80e pcs or general solenoid Q

thanks, it doesn't say anything on the voltage on the wires of the solenoids. like i said, i get voltage on pink black. so that basicly means it tries to shift into first gear. i thought maybe somehow they mixed something up inside the transmission and connected pinkred to pinkblack and visa versa.
it felt like it was in first gear, but that the stupid hose from the turbo blew off.
i just want to know if the 12v on that wire is good.
 

JSM

Active member
Re: 4l80e pcs or general solenoid Q

its claiming PWM hence the lack of voltage but I suspect you will see 12v if you put 1 lead to that, another the a 12v source....

I personally think something is wrong inside trans...valve stuck, solenoid bad...something. Your tranny guy that did trans didn't think so but I do.
 

bezerk

New member
Re: 4l80e pcs or general solenoid Q

its claiming PWM hence the lack of voltage but I suspect you will see 12v if you put 1 lead to that, another the a 12v source....

I personally think something is wrong inside trans...valve stuck, solenoid bad...something. Your tranny guy that did trans didn't think so but I do.

i think you might be right, but at the time being, before dropping the pan, i'm trrying to see if the pcs is sending out the good stuff too the trans. if i can get it to try to shit, i will drop the pans, and try it again, and see if one solenoid is broken or something.

the other bad thing is that soimebody didn't tighten the transmission lines. so i had to take them off, and geuss what...they were routed next to the starter. so 1 line got burned and is leaking,
i bypassed the cooler for the time being. thanks for not tighteni ng the lines...u will get the bill for my new pavement :D
 

DaveP

Active member
Re: 4l80e pcs or general solenoid Q

thanks, it doesn't say anything on the voltage on the wires of the solenoids. like i said, i get voltage on pink black. so that basicly means it tries to shift into first gear.
i just want to know if the 12v on that wire is good.

With trans in neutral, key on, engine not running, you should have voltage on both the pnk/blk (A) and pnk/red(B), with reference to ground. Using a jumper, momentarily ground each solenoid. You should hear the solenoid 'click'. If you don't, something is not right.

Shift into D (engine running) and the controller should command sol A "on", which will ground pnk/blk, and you should now see "0 Volts" to pnk/blk (with reference to ground) because it is 'grounded' at the controller.

If you do not see 12V from each solenoid to ground on your meter, key on, eng not running, you need to fix this first. More than likely just a mistake in the wiring.
 

DaveP

Active member
Re: 4l80e pcs or general solenoid Q

i stripped the wires, and measured voltage on the wire for solenoid a while putting it in to drive. just wondering if that is a good thing or bad thing.

You should have 12V in neutral, sol A should go to 0V in drive.
 

bezerk

New member
Re: 4l80e pcs or general solenoid Q

ok, so bassicly if i see 12v on a sol wire at the output of the pcs it means it's not engaged.
if i see 0 volt or ,measure up resistance with ground it's engaged. correct?
 

DaveP

Active member
Re: 4l80e pcs or general solenoid Q

ok, so basically if i see 12v on a sol wire at the output of the pcs it means it's not engaged.

Correct.

if i see 0 volt................ it's engaged.

Correct.

....,measure up resistance with ground

You cannot reliably measure the state of solid-state devices using 'resistance' measurements. Stick to the voltage methods above.
 

bezerk

New member
Re: 4l80e pcs or general solenoid Q

thanks man. this is a big help. i think thhe solenoids are swapped.
i get power too 1, not too another. limp mode should have 12v on both.
 

DaveP

Active member
Re: 4l80e pcs or general solenoid Q

thanks man. this is a big help. i think thhe solenoids are swapped.
i get power too 1, not too another. limp mode should have 12v on both.

There is a third, common connection for 12V to all the solenoids, including TCC.

Would be easiest to drop the pan to figure it out. That way you can 'trace' the wires from the case connector to the solenoids.

Also be aware that the early 91-92 4L80e case connector and pigtail have connection issues. They can be very intermittant. The 93-up harness is a much more reliable set-up. The early style has flat sided pins. The later style has round pins. (I'm 90% certain I have that right). Just a heads-up.
 

Quickstop [UK]

Combating adversyty.
Re: 4l80e pcs or general solenoid Q

:popcorn:

man I wish I could be there and work on my truck. I am so sick of not having acess to it :(

Thanks for everyone trying to help out here.
 

Quickstop [UK]

Combating adversyty.
Re: 4l80e pcs or general solenoid Q

the other thing that I wasn't able to check was the harness.

The PCS guy kept mentioning that a FWD vs AWD 4L80E had different wiring and that might have somehting to do with it - so the harness might be the wrong type - they sent two so the mistake might not be there.

Have you got the PCS wiring diagram for the harness? I think pins 53 and 59 from the PCS Trans computer go to the solenoids. Not sure if that helps.
 

bezerk

New member
Re: 4l80e pcs or general solenoid Q

update.
the pcs is giving out the right output. but it's missing gear 1 and 4. so solenoid A for some reason doesn''t do it's work. it's clicking, but the click sounds more shallow compared to the other solenoid.
hte tcc lockup works though.
i ordered 2 new solenoids, and hope this fixes the problem. if the problem remains. i really don't know where the flaw can be.
 

Quickstop [UK]

Combating adversyty.
Re: 4l80e pcs or general solenoid Q

If you put it in manual mode then you can select a specific gear. Let me know if you'll need that and I can go through it on my computer with you.

thanks for this.

insurance won't payout for the cladding - :rant:

I'm not going to pay for the rest of the shipping then.
 

bezerk

New member
Re: 4l80e pcs or general solenoid Q

If you put it in manual mode then you can select a specific gear. Let me know if you'll need that and I can go through it on my computer with you.

thanks for this.

insurance won't payout for the cladding - :rant:

I'm not going to pay for the rest of the shipping then.

yup, i had it on jacksstands. and drove the piss out of it. did manual. dynomode in 1 and 2th rpm and miles staid the same. using the tcc lockup even makes it easier to find gears. so 1 and 4 are not working.
 
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