Ok, i got 4th gear back after changing the pressure control module. I aslo updated the wiring harness inside and out of the case, which should have been done when it was rebuilt. I still have the driver quad module code and tcc does not lock. The manual shows it must not be getting correct voltage?
My #1 questions is : what is the driver quad module?
Inside the ECM there are output driver chips, each one contains 4 output driver transistors... they come in fours, so "quad module"...
Each driver transistor is able to either source or sink a large current... if the ECM detects an open-circuit or short-circuit at any driver transistor output, it sets a code like you see.
Check the TCC circuit:
- Is it open...?
- Is it shorted (to ground or power)...?
- can you command the TCC using the scqantool...? If so what are the on and off voltages on both sides of the TCC solenoid...?
How do you have the TCC circuit wired up...?
Ok, the truck is a obd1 so i can not to my knowledge turn the solenoid on or off with the snap on scanner. THe tcc solenoid gets 12 volts threw the main tranny harness and should if i understand right be grounded to apply, my tan black wire is going to e10.
Should there be a wire on e11? There is not one there?
ftp://ftp.diy-efi.org/pub/gmecm/manu...427/95pcm3.jpg
Where does e11 wire go or come from? It shows a brown wire for pmw tcc solenoid control? I dont have one
E10 = 4L60E TCC (on/off) signal
E11 = 4L60E TCC PWM signal
4L60E: both signals are needed to apply the TCC:
the TCC PWM signal is ramped up and the TCC (on/off) signal is switched ON.
NOTE: whenever the TCC (on/off) signal is off, the ECM will still cycle the TCC PWM signal up/down.
4L80E: has only one circuit to apply the TCC: TCC PWM.
From Stop-TCC-unlock-when-coasting:
So you can't use the 4L60E TCC PWM signal to control the 4L80E TCC PWM circuit...Originally Posted by joecar
...
4L80E has this circuit:
- TCC PWM,
To lock TCC, the PCM drives TCC PWM to some high value.
4L60E has these circuits:
- TCC PWM,
- TCC Enable,
To lock TCC, the PCM drives TCC PWM to some high value and drives TCC Enable to ground (i.e. both required).
4L60E is further complicated by the fact that the PCM will spike TCC PWM up/down while TCC Enable is off
(the HMTG book says it parks the TCC PWM solenoid at 90%, see here).
Edit: the TCC Enable solenoid is also just called the TCC solenoid.
do this instead:
- use 4L60E TCC (on/off) to directly drive the 4L80E TCC PWM circuit;
- use 4L60E TCC (on/off) to gate 4L60E TCC PWM thru a relay to the 4L80E TCC PWM circuit (see posts #26, #27, #29 below).
Last edited by joecar; November 5th, 2011 at 10:50 AM.
Okay, if i want to override the ecm to manually lock up the tcc, is there a way? Thanks
You have to ground the ground side of the 4L80E TCC PWM solenoid (wire a switch from the TCC PWM signal wire to ground).
Thank god! I disconnected the e10 wire and hooked it directly to ground and it finally locks the tcc up!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! First time ever the tcc worked.
Whatever the problem is it has to be in the ecm not allowing the circut to ground.
Now any ideas? Could there possibly ne a issue with my prom?
Several things are required (from what I can remember, this is an older ECM... what does your manual say...?):
- ECT must be up to temperature,
- VSS must be above some minimum,
- brake switch must be indicate brakes are released,
- gear must be 3rd or 4th.
Maybe the ECM doesn't like that E11 (4L60E TCC PWM) is open... you may have to connect a resistor between E11 and power (i.e. to look like a solenoid).
ok, i hooked my test light to a 12volt power source and shoved the test light in e11. I drove the truck down the highway, in 3rd and 4th the test light wood light up when i was going a steady speed. I then knew that the circut was opening a ground circut. And the Driver quad module code went away, but still my tcc wire in e10, i had no tcc work.
I tried the same test on e10 and i can never get a ground circut to open.
I swaped the tan (ground) tcc wire to e11 and drove the truck with nothing in e10. The truck for the first time in the build drove threw all 4 gears with the tcc locking up as need in 4th and i believe in 3rd if you are going the right speed.
Does this make no sence? Any idea why e10 never grounds?
Thank you so much for the help, i have been fighting this problem for right at a year. The past few months, i would work on a few days, then park it for a month bc i was so sick of it. Then the cycle would repeat. Now if things go right, a front driveshaft, new tires and it will finally be done!!! Thank you
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