OK so WTF did I do wrong now? 2nd gear switch please help!

[90Pioneer]

I'm *trying* to wire in a switch so I can control when the XJ says in second gear or not.

Using this writeup http://www.bigoffroad.com/bigpages/bigtech/2ndgear.htm

here's what I've done:

Spliced into the yellow D16 wire and ran the new wire to my "12 volt supply" terminal in my rocker switch.

I then placed in a diode on C15, the violet wire, with the grey circle pointing towards the harness connector. Then behind the diode, I spliced in another wire and ran it to the "accs on" terminal for my rocker switch.

Then I spliced a ground for the switch into another ground wire.

While out on the "test drive", the tranny goes from 1st gear to 3rd. It doesn't to second, and it wont shift into overdrive either. This is with the switch off (unlighted), and the transmission in "D".

When I move the tranny into the 1 - 2 position, it'll start in 1st gear, but it wont shift out of first gear until I flip the switch, and then goes into second.



Does anybody have any ideas wtf could be wrong? I've already double checked which wires I spliced into.

 

[90Pioneer]

I just took everything off and it is mostly back to normal. When in "D", it'll shift into first, second, third, overdrive, etc.

However when I put the shifter into the 1 - 2 position, it doesnt shift into second.

WTF is wrong?

 

[BrettM]

When I move the tranny into the 1 - 2 position, it'll start in 1st gear, but it wont shift out of first gear until I flip the switch, and then goes into second.

that's exactly what it's supposed to do:

Summary of what you did or what you are about to do =

We are bypassing the TCU unit and controlling the 1-2 transmission section with a toggle switch.

 

[90Pioneer]

that's exactly what it's supposed to do:

Yes, I entirely understand that is what it's supposed to do.

In my post I wrote:

"While out on the "test drive", the tranny goes from 1st gear to 3rd. It doesn't into second, and it wont shift into overdrive either. This is with the switch off (unlighted), and the transmission in "D"."

This is what I am wondering about.


Now that I've pulled everythign back off, with the tranny in the 1 - 2 position, it will no longer shift into second gear by itself. Shifts into it fine while in 3rd or in D.

 

[BrettM]

the way they wire the switch, it only gives you control over second with the shifter in the 1-2 position. the tranny will normally not shift to second in this position, at least not at any reasonable RPM.

I have come up with a full manual control for the AW4, without using a TCU computer, and giving full manual shifting all the time. I have been using this for several months now in my MJ, with at least 5,000 miles on it, no problems. I say all this to let you know that I understand very well the AW4 electronics. You can check out my shifter at http://awshifting.bravehost.com or there's a post here: http://www.pirate4x4.com/forum/showthread.php?t=242965


anyways.....

if you want to be able to flip a switch and have the tranny go into second gear, no matter whether your shifter is in 1-2,3,or D this is what you need to do:

-forget the yellow wire. put it back the way it was.
-run a wire from an ignition only power source (on the fusebox, or the radio power wire) to a 3A fuse.
-from the fuse run the wire to the toggle switch you have.
-from the toggle switch, bring 2 wires from the other terminal.
-put a diode on both of those wires, with the flow going away from the switch
-splice one to C15 and one to C16, tapping into those wires, leaving the stock circuit too
-now you're done. flip the switch in 1-2,3, or D and it will go into 2nd. just don't do it while you're going 80mph. when the switch is off it will drive 100% stock. if it doesn't, you probably screwed up something with the diodes. they have to be the right kind, facing the right way, and if they get too much heat when you solder they can be damaged.

 

[90Pioneer]

Thanks Brett. Actually my original plan was to just able able to switch into second when I'm in the 1 - 2 position, just like the write up shows. This is still what I would like to be able to do.

What I don't understand, is that I had it set up exactly the same way it shows in the wiring diagrams and the directions in the write up.

After returning it to stock, I brought it up to about 3k rpms in the 1 - 2 position, and it still didn't shift to second. Being in first gear at 3k RPMS (15 - 20mph), and not shifting into second is normal?




I also forgot to mention, before I pulled all of the wires off, I tried removing the diode, to see if it would work. I got the same results... While in D, switch off, it would skip second, and not shift into overdrive.

 

[BrettM]

let me get this straight:

you had it in the 1-2 position, were at a stop, switch in the off position, got on the gas and started going forward, flipped the switch to the on position, and the tranny didn't shift, stayed in 1st?

 

[90Pioneer]

let me get this straight:

you had it in the 1-2 position, were at a stop, switch in the off position, got on the gas and started going forward, flipped the switch to the on position, and the tranny didn't shift, stayed in 1st?

When I had the switch wired in, from a stop, in the 1 - 2 position, the tranny would not shift into second, until I flipped the switch. Just how it's supposed to be.

When I turned the switch off, and placed it back in D, and took off from a start, it would start in first, skip second, go to third, and not shift into overdrive either.


Now I pulled everything I wired in today off, just like stock, and when I put the tranny in 1 - 2 setting, it will not shift to second. However, when I put it in 3rd, or D, it goes 1, 2 ,3, overdrive just like it should.

 

[BrettM]

okay, I think I understand what you're saying now. It works perfectly like the writeup says when in 1-2, but it has screwed up your 3 and D positions. Right?

I also forgot to mention, before I pulled all of the wires off, I tried removing the diode, to see if it would work. I got the same results... While in D, switch off, it would skip second, and not shift into overdrive.

knowing how the logic of the circuit works, this really doesn't make sense. is it possible it's doing 2nd and 3rd only?

 

[90Pioneer]

Bret, here's why I assume it was skipping second...

With the switch off, taking off from a start everything seems normal. Gain a little speed, and I wait for the shift. Instead of acting like normal, when it upshifts, it felt like it shifted into the bottom of a gear I was not going fast enough for. I am positive it shifted into 3rd gear, but it would not shift into overdrive. I also don't think it was downshifting properly either. When I braked, RPMS dropped, but when I gave it gas again, it felt like I was once again, in the bottom of a gear I was moving to fast for.

But I am 99% sure it was skipping second.

 

[BrettM]

i'm really busy right now, but I'll sit down and think about it a little later, and run through the wiring schematics and possibilities.

 

[Eagle]

I just took everything off and it is mostly back to normal. When in "D", it'll shift into first, second, third, overdrive, etc.

However when I put the shifter into the 1 - 2 position, it doesnt shift into second.

WTF is wrong?

Basically, you're screwed. I talked to a guy at NAC Fest who did the exact same thing you did, with the exact same results. He has been driving around for a year now with no second gear.

That write-up is obviously flawed. On the bright side, another friend tried following one of those write-ups and toasted the TCU in his father's XJ. You got off light.

 

[90Pioneer]

Basically, you're screwed. I talked to a guy at NAC Fest who did the exact same thing you did, with the exact same results. He has been driving around for a year now with no second gear.

That write-up is obviously flawed. On the bright side, another friend tried following one of those write-ups and toasted the TCU in his father's XJ. You got off light.

I have second gear just fine, it just wont shift into it when I am in the 1 - 2 position. All other times it acts as normal.

Tons of people have done this mod, and the write ups are practically the same on bigoffroad and go-jeep. Why didn't the other people get the same results as I did?

And if I did cause some actual damage, the only thing I could have fubared would be the TCU, right? Just put in a new one and I should be golden (back to there I started in the first place)?

 

[90Pioneer]

i'm really busy right now, but I'll sit down and think about it a little later, and run through the wiring schematics and possibilities.

That would be fantasitc!!!! Thanks Brett!

 

[4WDXPRT]

Why don't you just email Troy Morris in Colorado as he did the write up...I actually own his XJ that he did all these mods too and I use the one/two switch all the time. His address is still the correct one at the bottom of the Bigoffroad.com article. I know he read through the FSM and figured out all the wiring on his own. I would suspect that the diode may be the wrong kind or something.

I can take some digitals of his rig and show you how he actually wired it.

I'm sure he would be more than happy to go over the install.

 

[90Pioneer]

Why don't you just email Troy Morris in Colorado as he did the write up...I actually own his XJ that he did all these mods too and I use the one/two switch all the time. His address is still the correct one at the bottom of the Bigoffroad.com article. I know he read through the FSM and figured out all the wiring on his own. I would suspect that the diode may be the wrong kind or something.

I can take some digitals of his rig and show you how he actually wired it.

I'm sure he would be more than happy to go over the install.

Actually I'm one step ahead of you and have already fired off an email to him.

I actually tried removing the diode, and got the same results, so I know that wasn't the problem.

A picture of the TCU with the wiring splices would be great! Then I can compare that to my own, and see where/if I went wrong. Although I would bet my life I had it set up exactly the way he describes it in the write up.

Thanks

 

[Cheapjeep2]

Hey, This is Troy, I got your email, I will read through the thread as time permits here at work and will try and figure it out. BTW, the process is not flawed as 100's of folks have donet his mod with total success so we just have to figure out what the problem is.

 

[Inisadow]

Just wanted to clarify things a little here. Pioneer In STOCK form(no mods done at all to it) in 1-2 the AW-4 will not shift into 2nd unless its over 4000rpms at least, This is why people do the 2nd gear shift button, for the most part. So your jeep is perfectly fine after taking the stuff off.

 

[Cheapjeep2]

90Pioneer,

This should be really simple to fix I think I know where your problems are.

1st. Inisdow is correct ""Just wanted to clarify things a little here. Pioneer In STOCK form(no mods done at all to it) in 1-2 the AW-4 will not shift into 2nd unless its over 4000rpms at least, This is why people do the 2nd gear shift button, for the most part. So your jeep is perfectly fine after taking the stuff off.""

When the tranny shifter is in the 1-2 position the tranny will not shift to second gear until your RPM hits 4K-5K RPM. If you have never experience it feels like something is broke until it violenly shifts to second with the motor racing... This is normal.

2nd. It sounds like from what you have wrote that everything is wired correctly. First hook everything back up with out the diodes. You won't hurt anything. Once you get it working, add the diodes. If it quits working, the diodes are backwards and you can simply turn them around.

3rd. The Problem. I have experienced and have had others report as well that when occasionally when using a an illumiated switch the mod will act up or won't work right. I basically believe this has something to do with the ground wire on the switch that is used to make the connection for the illumination. When I originally wired this mod I had a switch like you described, it didn't work very well and acted funny, I purscheded a simple Toggle switch with out the light that has one of those on-off cover plates. When I used this everything worked fine. I concluded that this is due to the ground leaching through the switch and interferring with the signals on the TCU. Wire everything like you did with a standard toggle and let me know the results. If it works, add your diodes and enjoy it. If you are still having problems we'll look deeper.

Cheapjeep2

 

[Cheapjeep2]

90Pioneer...

Quote: "While out on the "test drive", the tranny goes from 1st gear to 3rd. It doesn't into second, and it wont shift into overdrive either. This is with the switch off (unlighted), and the transmission in "D"."

This is the problem I had. This is what the ground for the illumination on the switch was causing.