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The MANU switch. Is this an on/off switch? Or just a push switch / momentarily switch?
 

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Arnout said:
The MANU switch. Is this an on/off switch? Or just a push switch / momentarily switch?
I thought it was a momentary switch just like the TRAC switch. I think everytime you start the car it defaults into auto mode so you would have to press it every time.

I could be wrong though. I have never actually driven an auto mkiv before.
 

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You have to turn it on if you re-start the car. IT just allows you to have full manual shifting over the auto, but it wont kick into OD (at least on my car it doesnt).

Good for parking lots, lock it in 2nd, so you dont get the annoying thump from 1st to 2nd about 5 times! As soon as it drops below 15 mph, it goes into 1st, rises back to 15 mph, back into 2nd. Thump!

I am working on a modification to the shifter to lockout neutral and make the shifts more positive. How many times have you gone from 1st to 3rd, or 2nd to neutral??? Too many!! It is a very poor design that needs improvement.

I will be posting the results very soon..........

Al
 

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Re: Re: manual switch on auto tranny

Mary-Kate Olsen said:

I thought it was a momentary switch just like the TRAC switch. I think everytime you start the car it defaults into auto mode so you would have to press it every time.

I could be wrong though. I have never actually driven an auto mkiv before.
yeah it resets when you cut the car off.
If that's what you call momentary.
I guess you could say it's electronic, not analog.
 

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Does anyone know if the manu button assembly can be fixed. My button does not stay depressed and pushing it does not activate manu mode. No modifications trac is on and functional
 

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It does not stay pushed in.

Its not a “throw” switch. You push it in to turn MANU on and then push it again to turn it off.

Hence what the others said about momentary, it’s only making contact the “moment” you have it depressed.

In a circuit like that, pushing it in pulls ground high or low depending on the current state. In a throw switch, the circuit is completed and stays that way until you switch it off again.

It’s like your TRAC button. But unlike your emergency flasher button.

If it won’t activate, do you still have your TRAC ECU? Checked the fuse? Relay? Bulb good? Cleaned the switch harness and switch contacts?
 

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It does not stay pushed in.

Its not a “throw” switch. You push it in to turn MANU on and then push it again to turn it off.

Hence what the others said about momentary, it’s only making contact the “moment” you have it depressed.

In a circuit like that, pushing it in pulls ground high or low depending on the current state. In a throw switch, the circuit is completed and stays that way until you switch it off again.

It’s like your TRAC button. But unlike your emergency flasher button.

If it won’t activate, do you still have your TRAC ECU? Checked the fuse? Relay? Bulb good? Cleaned the switch harness and switch contacts?
Hi,
So an update this evening the manu light is always on when in P. However in L, 2, or D it disappears and wont turn on. Car is stock no mods to ecu or anything. Bulb is good, fuse is okay, i will try and check the harness.
 

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Have you tried to pull codes?
The shop that i went to only said code 42 speed sensor. But we all know that wasnt gonna do squat. So right now im at maybe button assembly is faulty. Or some threads state its an ecu problem. But no other codes.
 

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Code 42 is actually one that causes some grief, have you done the pink wire mod?
Not yet. Correct me if im wrong but if my Odometer and cruise control work, doesnt that mean the speed signal is okay, meaning the odometer isnt messing with the signal? (Cold solder problem). I dunno if its related but my speedometer also has trouble going over 45-50mph while im doing 65-70. So im also trying to get enough courage to change the capacitors.
 

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So the a340e has two speed sensors. One sensor looks like VSS1 but it’s used to measure the forward drum speed. That one is further toward the front of the trans.

They look like cam position sensors.

The deal is though, and I may have this backwards, VSS1 is considered the primary speed sensor, it runs through the odometer circuit and it’s signal (waveform) is smoothed out using a buffer circuit to feed a clean signal to the ECU, if VSS1 fails, it will use VSS2 as a backup, which is a sensor that is opposite side of VSS1, both are toward the back but #2 has a plastic gear that turns a shaft that slides in to VSS2.

The drum speed sensor and VSS1 look the same.

If you have the code for one of them, replace it, they used to be expensive but you can get AISIN branded speed sensors on Amazon and EBay cheap now.

You can have a bad odometer and/or bad solder joints in the odometer and it still count miles and your speedo be off. That is why a lot of people bypass the odo buffer circuit to just send the signal straight from the trans to the ECU.

From your other threads, you likely have one or more problems, it looks like you have at least one bad VSS and a jacked up ECU too. Very common.

When my ECU was failing, sometimes I would be going 60 or 70 and it would be stuck at 35mph. Even when I stopped at a light it would slowly creep down. I couldn’t pull codes from it, AC was all stupid, cruise wouldn’t engage, idled like a fuel rich race car, various other stupid things and etc.

Last but not least, the capacitors can also fail in the speedo cluster too. Search for posts by Stu Hagen - you will learn a lot from those.

In the end, I have a functional vehicle, reliable as hell but I still have weird shifting problems. Even after the ECU rebuild, full sensor and connector replacement, my car will gear search while going down the road, shifts at 3500 rpm in every gear, won’t hold manual selected 1st, it auto shifts in to 2nd. Driving it like a good normal car, you never know, it’s just when I want to show out it gets stupid. But I have no codes, speedo is right, trac and manu work. Just don’t expect a full throttle downshift. :)

The a340e transmission control is janky as hell and if one thing is off it will screw up.

I’m going to do like others and go stand alone when I get the time. AEM has one that will control the a340e stock crapbox.
 

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So the a340e has two speed sensors. One sensor looks like VSS1 but it’s used to measure the forward drum speed. That one is further toward the front of the trans.

They look like cam position sensors.

The deal is though, and I may have this backwards, VSS1 is considered the primary speed sensor, it runs through the odometer circuit and it’s signal (waveform) is smoothed out using a buffer circuit to feed a clean signal to the ECU, if VSS1 fails, it will use VSS2 as a backup, which is a sensor that is opposite side of VSS1, both are toward the back but #2 has a plastic gear that turns a shaft that slides in to VSS2.

The drum speed sensor and VSS1 look the same.

If you have the code for one of them, replace it, they used to be expensive but you can get AISIN branded speed sensors on Amazon and EBay cheap now.

You can have a bad odometer and/or bad solder joints in the odometer and it still count miles and your speedo be off. That is why a lot of people bypass the odo buffer circuit to just send the signal straight from the trans to the ECU.

From your other threads, you likely have one or more problems, it looks like you have at least one bad VSS and a jacked up ECU too. Very common.

When my ECU was failing, sometimes I would be going 60 or 70 and it would be stuck at 35mph. Even when I stopped at a light it would slowly creep down. I couldn’t pull codes from it, AC was all stupid, cruise wouldn’t engage, idled like a fuel rich race car, various other stupid things and etc.

Last but not least, the capacitors can also fail in the speedo cluster too. Search for posts by Stu Hagen - you will learn a lot from those.

In the end, I have a functional vehicle, reliable as hell but I still have weird shifting problems. Even after the ECU rebuild, full sensor and connector replacement, my car will gear search while going down the road, shifts at 3500 rpm in every gear, won’t hold manual selected 1st, it auto shifts in to 2nd. Driving it like a good normal car, you never know, it’s just when I want to show out it gets stupid. But I have no codes, speedo is right, trac and manu work. Just don’t expect a full throttle downshift. :)

The a340e transmission control is janky as hell and if one thing is off it will screw up.

I’m going to do like others and go stand alone when I get the time. AEM has one that will control the a340e stock crapbox.
bc2jz. I'm in the same boat as you. I put mine it manu mode and first and it will be in second on its own. Tried everything I have been able to think off to try and sort this but no luck. Let me know if you find a fix.
 

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Another poster on here had the same issue and he said it went away after he went stand-alone.

It’s something that is screwy in the ECU’s even after a repair.

Of note, when I parked the car for several years it didn’t act this way. I had it rebuilt and once I started driving it again is when this started.

The only thing that I think would cause this in the trans would be something valve body related.
 

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Another poster on here had the same issue and he said it went away after he went stand-alone.

It’s something that is screwy in the ECU’s even after a repair.

Of note, when I parked the car for several years it didn’t act this way. I had it rebuilt and once I started driving it again is when this started.

The only thing that I think would cause this in the trans would be something valve body related.
New ECU fixed all! Gear box is shifting like buttah! Manu/Ect button/light is working! Thanks man! Would have never guessed it was the ecu.
 

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New ECU fixed all! Gear box is shifting like buttah! Manu/Ect button/light is working! Thanks man! Would have never guessed it was the ecu.
Where did you get a "new" ecu?
 

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New ECU fixed all! Gear box is shifting like buttah! Manu/Ect button/light is working! Thanks man! Would have never guessed it was the ecu.
Good deal! Happy to hear.

I don’t think I asked, but your ECU before you found a replacement, did you ever have anyone look at it and try to repair it?
 

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Nah here on the islands we don’t have any reliable services that i have seen. The ones that I have seen have terrible reviews. But I do plan to fix the old. one a member recommended Tanin auto electronics. They only advertises fixing is300 GS and a few others but they did email me back asking what car I had and what kind of problems. Then to contact them if the ecu was the problem so I figure they can repair it. I’m gonna contact them when I get the results of my compression/Leakdown test (been bubbling in the overflow tank). No sense fixing anything else if the engine needs a tear down 😞.
 
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