E4OD T/C manual lock switch

[zigg]

I finally got around to finishing up my E4OD manual override switch. I put in 2 switches. One is a single pole double throw ,and the other is just an on/off.

Originally, when I put this in, and had the computer out of the loop, the OD switch would start to blink as soon as the trans went into 4th, and the computer tried to lock up the Torque Converter. The trick is to fool the computer into thinking it's still working the solenoid. I found a link to a guy who did this on his 2002. You put a 20,000 ohm 10 watt resistor inline with the computer to ground and this solves it. Sounds complicated? Not really.

So, the computer is connected to the center of the switch, and on the one side, it is switched via the resistor to ground. On the other side, it is as factory, and operates as from the factory. The second switch is connected to the wire that comes from the T/C lockout solenoid, and can be flipped anytime. When it is in the on mode, the T/C solenoid is directly to ground. So, the T/C can be locked anytime, when the switch is in the "Auto" mode, or when in the "manual" mode.
In town, I run in manual. It shifts 1,2,3,4 and no lockup. I can manually lock it anytime I want, and the shifts are nice and smooth and spaced as they should be. In auto, it shifts as from the factory, and the lockup comes on at about 35mph in 3rd.

I think it is a real nice mod for those of us with the Auto, and it gives total control over the trans at any time.

I'm at work, just now, but when I get home if anyone is interested, I'll draw up a short schematic and post it later...

Zigg

 

[LCAM-01XA]

Well of course we're interested in teh wiring diagram, what kinda question is that? lol

Yeah man, draw up something, I suck at understanding words but I can work with drawings pretty good. A question tho, where did you cut the wire for the lockup, near the ECM in the engine bay?

 

[yARIC008]

I just wish there was an easy way to rig up a tiptronic shifting so you could really have TOTAL control and choose your gear too. Either that or it'd be nice to be able to mod the trans computer without having to spend an arm to buy a different better computer.

Cool about tricking the computer into thinking it's still working though. I never had that problem of setting off the blinking OD light when I did mine though.

 

[oldmisterbill]

I may be wrong but Okie Gringos Bauman unit does that.It leaves push button control for the driver to shift as he likes.

 

[zigg]

I may be wrong but Okie Gringos Bauman unit does that.It leaves push button control for the driver to shift as he likes.

I think you're right Bill, but that there unit cost over $500 bones, mine cost a total of about $10. You can always move the shifter from 1,2,D,OD if you really want.

The manual switch on mine also allows you to manually lock the T/C anytime wether in Auto or Man setting, this is very handy when descending downhill with a load, or to prevent the unlock every shift, and every time you take your foot out of it, or put the brake on for a sec. Should make the T/C last much longer.

Here's the pic. I tapped into the wire down under the drivers side floorboard at the framerail. It is a purple wire with white stripe in the harness that goes to the trans. You simply cut it, and then run extensions up into the cab so you can connect them to the switch. The one from the trans will be the T/c wire, and can be identified by turning the key to on, with engine off, it should have 12v on it. The other end goes to Tcm in the computer module.

The resistor is required inline to fool the computer into thinking it is still connected to the solenoid in the trans, when the switch is in the "manual" mode. Seems like not all tranny's need this, but if the computer isn't connected to something, at least on mine, it goes into limp mode instantly when 4th(od) kicks in.

I put the second switch over behind the turn signal switch on the dash, so that no-one can accidentally bump it.
Now, I have Auto for when the wife drives. Acts as from the factory.
I have manual, and lets the trans shift 1,2,3,4, with no lockup, and then I can flip the other switch anytime whether in Auto or Man position to lock the T/c, and it will stay locked until this switch is released.

The only down side, is that you must remember to unlock the thing when coming to a stop, or it is like leaving the clutch out with the trans in gear.
I haven't done it, but I'm sure it would be a bit nasty. Might even do some damage, although I've heard a couple guys say they have done it, with no lasting probs.

There's other ways to wire it, but this is what I wanted, and so far I'm absolutely delighted with it!!

 

[RedTruck]

Zigg,

What happens when you have the spdt in auto and the spst in off?

I don't have an e40d...I'm just curious.

Looks like a great setup.

Paul

 

[RedTruck]

Never mind I should have just read further.

Paul

 

[LCAM-01XA]

Zigg, I'm looking at your diagram, and I'm wondering shouldn't there be a +12V supply on the side of the 20k resistance, and not a ground? I mean if the ECM is the ground, and the TC is the +12V supply, if you have it wired like you show on the diagram then in manual mode you end up connecting ground to ground, which means the ECM will not register the current flow and will go limp-mode on you. My ideal setup would be only one switch, likely a DPDT thing, with one end position manual unlocked, the middle position on auto, and the other end position manual lock, but I gotta work a bit on the circuitry as there will have to be a relay involved in that whole mess..

 

[LCAM-01XA]

Okay, here it is:

a) red circuit - automatic mode - middle position of the DPDT switch, the current flows from the T/C through the normally-closed relay to the ECM, the diode prevents if from feeding back through the resistance and to relay's command circuit.

b) blue circuit - unlocked mode - top position of DPDT switch, current flows from the T/C to the DPDT switch and ends there (open terminal), on the other end the external 12V current now flows through the DPDT switch to feed the relay command circuit (disconnects the T/C from the ECM by interrupting the red circuit) and also through the resistance and the diode to the ECM.

c) blue circuit - locked mode - bottom position of DPDT switch, current flows from the T/C through the DPDT switch and to ground, on the other end the external 12V current now flows through the DPDT switch to feed the relay command circuit (disconnects the T/C from the ECM by interrupting the red circuit) and also through the resistance and the diode to the ECM.

Essentially the only difference between converter unlocked and locked mode is the current flow from the tranny, the external 12V supply feeding the ECM and triggering the relay has the same path in both situations. In auto mode there's no current flow through at all the DPDT switch.

Questions, comments?

 

[tuckerd1]

Zigg, I'm looking at your diagram, and I'm wondering shouldn't there be a +12V supply on the side of the 20k resistance, and not a ground? I

The way I see it the PCM supplies +12v to the TCC solenoid which in turn is grounded. The resistor is replacing the TCC solenoid while in manual mode. The PCM supplies +12v to the resisitor which in turn is grounded. The PCM sees the effective resistance of the TCC solenoid thru the resistor.

 

[LCAM-01XA]

Don, that would be correct if the ECM is the one supplying the 12V to the TCC, however are we sure it the ECM is the power supply, and not on the receiving end? Tis typical for Ford ECM to be the grounding element in the circuit, as in there's a separate power feed (usually through a relay off the main key-on circuit), and the whole thing is always energized, but there is actual current flow only when the ECM closes the circuit and grounds its end of it. So really, can someone confirm for certain whether the ECM is on the supply or the receiving end of the TCC circuit?

 

[94johnh]

So Zigg

What happens if you stop without turning it off ?. I like the idea of having a manual mode BUT ! being a geezer I know i would forget....


john

 

[zigg]

Don, that would be correct if the ECM is the one supplying the 12V to the TCC, however are we sure it the ECM is the power supply, and not on the receiving end? Tis typical for Ford ECM to be the grounding element in the circuit, as in there's a separate power feed (usually through a relay off the main key-on circuit), and the whole thing is always energized, but there is actual current flow only when the ECM closes the circuit and grounds its end of it. So really, can someone confirm for certain whether the ECM is on the supply or the receiving end of the TCC circuit?

DOH!!!

You are absolutely correct. M.L.S.C. I dunno where I came up with that from. The 12v is supplied to the trans to all the solenoids in the trans commonly, and then the Computer provides ground as needed to activate each individual solenoid for each shift and then lockup. I have constant 12v to the resistor from the back of the cigarette lighter, and then through the resistor to the Computer in the manual mode. Dunno what I was thinking when I drew up that picture. I'll fix it up tomorrow. I'm going to do this up as another article on my web page...

Been a few days now, and so far it runs beautiful.!!

I assume if it is left engaged as you come to a stop, you'd get somemighty nasty shuddering, and then stall the engine via the trans. Couldn't be good for it though.

Zigg

 

[towcat]

guys-
I urge much caution when leaving the lockup engaged in coast mode and low speed mode. E4DOA's don't have much clutch material to handle such loads. Even with the billet front half torque converters, the material is not much more than 3/4"wide running the diameter of the torque converter. Do it one too many times and you will throw a code 62. I've done enough postmortems on these trans to know better. There is a shop that will cut open a converter for me at the tune of $60. Every suspected code 62 converter has come up with the same results. Completely burned up lockup clutch material.
Don't learn this one the hard way.

 

[LCAM-01XA]

Towcat, how about some way of disengaging the lockup at low speed? The cruise control for example does that, is there some wire that can be tapped so that it allows the manual lockup only when the cruise is allowed to operate, (whatever that speed is)? Like, use the signal that the cruise module "watches" so it knows when the truck has slowed down too much, and use the same signal for enabling/disabling the manual lockup? Or is that all done internally in the ECM, so there's really no external wire we can mess with?

Another thing that can be done is tap into the brake lights switch, and use that to trigger a relay that opens the TCC circuit and thus unlocks the converter? That oughta be easy to do...