Torque converter lockup override switch? (Prado)

rowinz · Post by **rowinz** » Fri Jun 15, 2007 3:52 pm

Anyone have any experience or (useful) thoughts on installing a driver-controlled selector switch to lock up torque converter (t/c)
From readings, ECT controlled trannies usually lockup in 3rd or 4th, needing other conditions to be met (engine temp, brake pedal not depressed, engine speed, road speed, etc).
From experience in the Prado, the t/c locks up when tranny selector in "L" (ie 1st gear), whether in low or high box.
I was going to install a manual ON/OFF switch on dash to activate t/c lockup solenoid so the engine and trans are directly linked if I so choose.

Was thinking of simply sending a energise signal to the controlling solenoid. Will this kill the ECT (with back current) or the tranny? This will require manually turning OFF as road speed drops. This is so I can crawl in Low 2 with direct connection engine-to-wheels.

Any advice appreciated. This is for 94 Prado 1KZ-TE with A343F trans

Next step might be manual selection of gear, but that seemed a bit too involved just at the mo.
Cheers
Rowan

wjw · Post by **wjw** » Fri Jun 15, 2007 4:15 pm

its doable... Ill see if I can dig out the docs I found...

Mattman · Post by **Mattman** » Fri Jun 15, 2007 6:21 pm

These guys do a manualised kit with torque converter control.

http://awshifting.com/kit.htm

Matt.

Shane · Post by **Shane** » Fri Jun 15, 2007 7:27 pm

rowinz wrote:Anyone have any experience or (useful) thoughts on installing a driver-controlled selector switch to lock up torque converter (t/c)
From readings, ECT controlled trannies usually lockup in 3rd or 4th, needing other conditions to be met (engine temp, brake pedal not depressed, engine speed, road speed, etc).
From experience in the Prado, the t/c locks up when tranny selector in "L" (ie 1st gear), whether in low or high box.
I was going to install a manual ON/OFF switch on dash to activate t/c lockup solenoid so the engine and trans are directly linked if I so choose.

Was thinking of simply sending a energise signal to the controlling solenoid. Will this kill the ECT (with back current) or the tranny? This will require manually turning OFF as road speed drops. This is so I can crawl in Low 2 with direct connection engine-to-wheels.

Any advice appreciated. This is for 94 Prado 1KZ-TE with A343F trans

Next step might be manual selection of gear, but that seemed a bit too involved just at the mo.
Cheers
Rowan

I have fitted a switch to my GQ safari,I removed the wire from TCU and just power it up with the switch(Dont power it up still connected to TransControlUnit)One of the best things I'v done for on road driving,you just have that little bit more control esp when short on power.
The toyota should be the same,just a matter of powering up the lock/up solenoid.

My friend what to do his 80# VX also.

Shane

matwelli · Post by **matwelli** » Fri Jun 15, 2007 8:03 pm

This is something I have been considering for the Pajero, whats it like having the extra control when offroad ?

wjw · Post by **wjw** » Fri Jun 15, 2007 8:17 pm

spent five minutes hunting for that info, the guys above are corret you just have to turn the lockup solenoid on, i'll be doing it eventually as I want to be able to lock the truck in 2nd for river crossings...

oldblue · Post by **oldblue** » Fri Jun 15, 2007 9:45 pm

http://www.toyotasurf.asn.au/forum/viewtopic.php?t=12654

Post by **Mark** » Fri Jun 15, 2007 11:24 pm

http://www.automatictransmission.com.au/release.asp?NewsId=12101 wrote:Eliminates all convertor slippage and convertor runaway on steep down hill descents allowing full 100% engine braking. Will stall engine if not turned off before stopping! Just like not engaging a Manual clutch before coming to a stop.

Allows for full time Lock-Up in any gear including 3rd when heavy towing greatly reducing transmission over heating, eliminating constant Lock-Up engagement and disengagement, Longer life expectancy of the Lock-Up plate and giving you greater fuel economy in all of the above circumstances.

Very interesting...

Shane, I am VERY interested in this lockup thing for my whale. I'm not really an auto man and whenever I drive on the open road I always say how I wished I had a manual. This may be a small compromise and I think it would be great for towing the boat.

Are you able to share a small "how to" on this mod for a Safari? Did you do something similar to this:
http://members.bettanet.net.au/~conody/Lockup%20Trans%20Switch.htm

Cheers

Shane · Post by **Shane** » Sat Jun 16, 2007 11:33 am

Much more simple than that set up,I just use a switch that powers up the solenoid with a relay.
It wont lock up in first gear on GQ models but well on the GU's.
I dont use it off road that much,but is handy when going up a long climb with a large group were you cant always go at the speed that best suits you(its like a gear in between gears)and is also good on sand/snow helps stop trans over heating.
Pic below of TCU with wire(Black tape) that controls lockup.DONT power up solenoid when still connected to TCU.

Shane

Dace · Post by **Dace** » Sat Jun 16, 2007 12:14 pm

above all good ideas but it would be possible to just splice the wire into the origional wire, you would need to put a diode (sort of one way valve for electrical current) between the splice and the ECU which will basically stop your override switch current going back up to the ecu while still letting the ECU lock the TC when it need to

maybe there is a sparky in here some where that could help

Post by **Mark** » Sat Jun 16, 2007 12:36 pm

http://members.bettanet.net.au/~conody/Lockup%20Trans%20Switch.htm

I believe that is what the "Control Relay" in the above setup does. It remains hooked up to the TCU and when the override is triggered the relay breaks the connection between the TCU and the lockup solenoid and diverts the connection to the manual override circuit.

That's what it looks like to me anyway :oops:

I'm not sure that I would bother with the foot switch or brake relay, but I like the idea of having it controlled by the TCU still when the manual override is disengaged.

Thanks for the photo Shane. I might go and plug my voltmeter into that wire and wee what happens when I go for a drive.

Mattman · Post by **Mattman** » Sat Jun 16, 2007 5:54 pm

Yep a diode should allow you to keep the connection to the TCU and do what you like with it.

Matt.

Post by **Mark** » Sat Jun 16, 2007 8:11 pm

So what sort of diode would you use and where would you get one? I have never done anything with diodes before but I like the sound of that option rather than using a relay setup (much simpler wiring, meaning less risk of cocking it up). I had a quick look on the Dick Smith website and didn't see anything that resembled a 12V ~10 Amp diode. What would you look for?

The research I have done has not come up with any mention of using a diode to solve that problem of feeding back to the TCU. Why would that be? Is there something we are forgetting?

Shane · Post by **Shane** » Sat Jun 16, 2007 9:08 pm

They use a constent(spell??)on relay that works like normal (auto operation)when switch is in off position and powers up the solenoid only in on position.that how I would do it anyway.

Also when you back probe(no pun

)the lock up wire the voltage should ramp up,doesnt just hit 24v's(just so you dont think its the wrong wire)

Shane

rowinz · Post by **rowinz** » Sat Jun 16, 2007 10:22 pm

thanks guys. I had thought of the diode setup because then the ECT unit is always working , and you have manual control also. Just not sure on what currents/voltages the ECT puts out. Other thought was a bypass switch, so disconnect the ETC to activate the manual switch.
I was gonna ask Toyota, see if they would know the correct current/voltages for the diode setup. You could also have a dash light to indicate the ETC lockup-signal. Just an additional track of what the ECT is doing.

Bill, OldBlue, you guys don't happen top know where the ETC unit is mounted in these Prados per chance - haven't had a chance to look yet)?
Solenoid : I assume it locks up when power is put onto it?

May not have a chance to do this for a while yet. No2 child was due yesterday...waiting, waiting...
ThxR

wjw · Post by **wjw** » Sat Jun 16, 2007 10:37 pm

Take the glove box inner lining out , its above that ;-)

kiwipete · Post by **kiwipete** » Sat Jun 16, 2007 11:06 pm

Mark wrote:So what sort of diode would you use and where would you get one?

Try DSE, its a 40V3A one, should do the trick.http://www.dse.co.nz/cgi-bin/dse.storefront/4673c3600130e98e273fc0a87f3306e8/Product/View/Z3252

Post by **Mark** » Sat Jun 16, 2007 11:18 pm

kiwipete wrote:
Mark wrote:So what sort of diode would you use and where would you get one?

Try DSE, its a 40V3A one, should do the trick.http://www.dse.co.nz/cgi-bin/dse.storefront/4673c3600130e98e273fc0a87f3306e8/Product/View/Z3252

Thanks. I might get a couple and have a play.

Mattman · Post by **Mattman** » Mon Jun 18, 2007 5:36 pm

The amperage should be quite low - you probably don't even need a relay to switch the solenoid.

If you locate the lockup solenoid on the trans you can unplug the connector and measure the resistance across it using an ohmeter.

amps = volts/resistance so amps = 14 or 24/whatever you measure. This will give you your current draw that you need to support.

If it's only a couple of amps then don't worry about a relay, a simple switch with the output spliced into the existing wiring along with a diode to prevent feedback to the TCU and you are all done.

Perhaps a light with the switch so you know when you are on override. Most switches will easily support 4-5 amps. Select a suitable power source that is fused as well that has capacity to spare and perhaps fuse your circuit as well.

Matt.

Torque converter lockup override switch? (Prado)

Torque converter lockup override switch? (Prado)

Re: Torque converter lockup override switch? (Prado)