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Dutchgixxer

How to remove power limitations 1st and 2nd gear

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I have derestricted the 1st and 2nd gear power limitations. I have made a simple scematic :

post-20539-073954900 1286865358_thumb.jp

post-20539-068319400 1286865405_thumb.jp

You will get falsh readings on the dash when 1st or 2nd gear are engaged.

I am busy decoding the serial link between ECU and dash.

To be continued

Edited by Dutchgixxer

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I have derestricted the 1st and 2nd gear power limitations. I have made a simple scematic :

post-20539-073954900 1286865358_thumb.jp

post-20539-068319400 1286865405_thumb.jp

You will get falsh readings on the dash when 1st or 2nd gear are engaged.

I am busy decoding the serial link between ECU and dash.

To be continued

While this looks feasible in some respects, I would caution that unless you know what the I/O interface properties are, you may be violating circuit constraints which would then risk a blown sensor or worse. I offer the following scenarios:

1. Each output of the GPS is an open drain that is asserted Low (or simply grounded) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired OR gate and will logically work.

2. Each output of the GPS is an open drain that is asserted High (or simply opened) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired AND gate and will NOT work as all 3 outputs must be asserted High simultaneously which will never happen.

3. Each output of the GPS is a CMOS type output that is asserted High (i.e. actively driven high) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a definite circuit rules violation as the output that is attempted to be driven high will be actively countered by the other two outputs which are actively driven Low, thus causing a near direct short to the supply voltage and maybe a fried GPS.

Perhaps you've already found that it does work as shown, in which case scenario #1 is most likely true. If it doesn't work, then beware of scenario #3 which could end up costing you some $$$ to fix.

Good luck in your efforts, I wish I could do the same but the DCT control needs to know the actual gear selection otherwise it would be constantly trying to downshift below third and never finding it.

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I have derestricted the 1st and 2nd gear power limitations. I have made a simple scematic :

post-20539-073954900 1286865358_thumb.jp

post-20539-068319400 1286865405_thumb.jp

You will get falsh readings on the dash when 1st or 2nd gear are engaged.

I am busy decoding the serial link between ECU and dash.

To be continued

While this looks feasible in some respects, I would caution that unless you know what the I/O interface properties are, you may be violating circuit constraints which would then risk a blown sensor or worse. I offer the following scenarios:

1. Each output of the GPS is an open drain that is asserted Low (or simply grounded) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired OR gate and will logically work.

2. Each output of the GPS is an open drain that is asserted High (or simply opened) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired AND gate and will NOT work as all 3 outputs must be asserted High simultaneously which will never happen.

3. Each output of the GPS is a CMOS type output that is asserted High (i.e. actively driven high) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a definite circuit rules violation as the output that is attempted to be driven high will be actively countered by the other two outputs which are actively driven Low, thus causing a near direct short to the supply voltage and maybe a fried GPS.

Perhaps you've already found that it does work as shown, in which case scenario #1 is most likely true. If it doesn't work, then beware of scenario #3 which could end up costing you some $$$ to fix.

Good luck in your efforts, I wish I could do the same but the DCT control needs to know the actual gear selection otherwise it would be constantly trying to downshift below third and never finding it.

Thanks for your reply.

I found from the honda scematic that if a gear is selected the ECU input is pulled to ground. ( your option 1 ) The screenshot with the color in it is a screenshot from the OEM honda scematic.

This mod is not working for a DCT.

I have added 2 scans of the OEM scematic.

schema L.pdf

schema R.pdf

Edited by Dutchgixxer

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This mod is not working for a DCT.

I was just gonna say that I doubt this would work on a DCT model, and you've already gone and said it.

I imagine it would play all sorts of havoc with a DCT....

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1. Each output of the GPS is an open drain that is asserted Low (or simply grounded) for a given gear selection.

2. Each output of the GPS is an open drain that is asserted High (or simply opened) for a given gear selection.

3. Each output of the GPS is a CMOS type output that is asserted High (i.e. actively driven high) for a given gear selection.

If the wiring diagram provided is correct then situation number one is almost certainly the design.

The diagram shows the switch being dropping to ground... so situaiton #3 is ruled out as there would be no source of voltage at the switch (per the diagram provided). Situation #2 would require a unique type of switch of the kind I have never encountered in years of servicing industrial equipment.

#1 is, by reasoning, almost certainly the case.... because the type of switch that drops only one lead to the ground would be of a very common type that I have seen in many different applications. From the engineering point of view I would think that the EE who designed the logic side of the circuit would have many logic chips available to choose from that had sinking transistor inputs.

However.... there is usually logic present in applications I have encountered that would sense multiple inputs when there should not be (failed switch, operator attempting to bypass a function or shorted wiring)... that would cause the logic chip to put out an error to the ECU and throw the program into a fail safe or keep run mode.

I hope gixxer gives this a try so our specualtion can be answered.

Edit: well that is what I get for replying to a post before reading to the bottom.... I guess gixxer has shown it is situaiton #1

And I also now notice that gixxer has negated the multiple input problem by snipping the wires above the jumpers.

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Guest notinline

I am thinking a plug and play right off the gear position switch where it leaves the crankcase "might " be the ticket here. I don't want to splice.

At your convenience , can someone count the number of wires coming off the gear position switch ? Photos of the actual connector if possible.

It should be left side of engine above the shifter . To locate it via a parts fiche ,see Ron Ayers and click crankcase.

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First off...congrats to dutchgixxer for being what appears, on the verge of solving the lower gear power limitation. But would someone help me out here? I may have missed it but in all the reading of posts, I have not seen it addressed why the VFR1200 was detuned in the first place. Somewhere....in Japan...around some engineering table, the decision was made to do this. On a bike that is already at or beyond the maximum consumer price point, why did they elect for the added production costs of the sensors and what-not for this detuning? Was it to make the rear tire last longer? Was it to keep the front wheel on the ground? Was it to keep the rear passenger on the seat? Was it to prevent over-torqueing the shaft drive system? Somewhere out there is THE valid reason this was settled upon in that engineering room. I'm like everyone else in that there is a never ending desire for more power but before I snipped or jumpered anything on my brand new bike, I would have to understand what was on the minds of the people that built it that way. I understand rev limiters and I understand max speed cutouts designed in some bikes but this detuning in those lower gears is for some other reason. Please anyone/everyone give me your best guess as to what the reasoning might be. Thanks in advance.

I have derestricted the 1st and 2nd gear power limitations. I have made a simple scematic :

post-20539-073954900 1286865358_thumb.jp

post-20539-068319400 1286865405_thumb.jp

You will get falsh readings on the dash when 1st or 2nd gear are engaged.

I am busy decoding the serial link between ECU and dash.

To be continued

While this looks feasible in some respects, I would caution that unless you know what the I/O interface properties are, you may be violating circuit constraints which would then risk a blown sensor or worse. I offer the following scenarios:

1. Each output of the GPS is an open drain that is asserted Low (or simply grounded) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired OR gate and will logically work.

2. Each output of the GPS is an open drain that is asserted High (or simply opened) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired AND gate and will NOT work as all 3 outputs must be asserted High simultaneously which will never happen.

3. Each output of the GPS is a CMOS type output that is asserted High (i.e. actively driven high) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a definite circuit rules violation as the output that is attempted to be driven high will be actively countered by the other two outputs which are actively driven Low, thus causing a near direct short to the supply voltage and maybe a fried GPS.

Perhaps you've already found that it does work as shown, in which case scenario #1 is most likely true. If it doesn't work, then beware of scenario #3 which could end up costing you some $$$ to fix.

Good luck in your efforts, I wish I could do the same but the DCT control needs to know the actual gear selection otherwise it would be constantly trying to downshift below third and never finding it.

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First off...congrats to dutchgixxer for being what appears, on the verge of solving the lower gear power limitation. But would someone help me out here? I may have missed it but in all the reading of posts, I have not seen it addressed why the VFR1200 was detuned in the first place. Somewhere....in Japan...around some engineering table, the decision was made to do this. On a bike that is already at or beyond the maximum consumer price point, why did they elect for the added production costs of the sensors and what-not for this detuning? Was it to make the rear tire last longer? Was it to keep the front wheel on the ground? Was it to keep the rear passenger on the seat? Was it to prevent over-torqueing the shaft drive system? Somewhere out there is THE valid reason this was settled upon in that engineering room. I'm like everyone else in that there is a never ending desire for more power but before I snipped or jumpered anything on my brand new bike, I would have to understand what was on the minds of the people that built it that way. I understand rev limiters and I understand max speed cutouts designed in some bikes but this detuning in those lower gears is for some other reason. Please anyone/everyone give me your best guess as to what the reasoning might be. Thanks in advance.

I have derestricted the 1st and 2nd gear power limitations. I have made a simple scematic :

post-20539-073954900 1286865358_thumb.jp

post-20539-068319400 1286865405_thumb.jp

You will get falsh readings on the dash when 1st or 2nd gear are engaged.

I am busy decoding the serial link between ECU and dash.

To be continued

While this looks feasible in some respects, I would caution that unless you know what the I/O interface properties are, you may be violating circuit constraints which would then risk a blown sensor or worse. I offer the following scenarios:

1. Each output of the GPS is an open drain that is asserted Low (or simply grounded) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired OR gate and will logically work.

2. Each output of the GPS is an open drain that is asserted High (or simply opened) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a wired AND gate and will NOT work as all 3 outputs must be asserted High simultaneously which will never happen.

3. Each output of the GPS is a CMOS type output that is asserted High (i.e. actively driven high) for a given gear selection. Then tying 3 output wires together into one input as you have shown is a definite circuit rules violation as the output that is attempted to be driven high will be actively countered by the other two outputs which are actively driven Low, thus causing a near direct short to the supply voltage and maybe a fried GPS.

Perhaps you've already found that it does work as shown, in which case scenario #1 is most likely true. If it doesn't work, then beware of scenario #3 which could end up costing you some $$$ to fix.

Good luck in your efforts, I wish I could do the same but the DCT control needs to know the actual gear selection otherwise it would be constantly trying to downshift below third and never finding it.

Did you see that youtube video of the kid that throws down his brand new gixxer as he guns it out of the dealership? Rear wheel just spins out like the tire was made out of plastic! Then down she goes...

I saw a video of the VFR1200 being driven by a journalist at a japanese track way back at the initial release and he spun out the rear wheel...saved it, but still... I have a feeling 'if you don't know what your doing' the torque at the rear wheel will bite you in 1st or 2nd gear in this new VFR1200, so Honda played it safe. That's all they needed, all kinds of stories about it being a 'dangerous' bike. I think that is why is has been restricted...poor man's traction control.

Brian

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I saw a video of the VFR1200 being driven by a journalist at a japanese track way back at the initial release and he spun out the rear wheel...saved it, but still... I have a feeling 'if you don't know what your doing' the torque at the rear wheel will bite you in 1st or 2nd gear in this new VFR1200, so Honda played it safe. That's all they needed, all kinds of stories about it being a 'dangerous' bike. I think that is why is has been restricted...poor man's traction control.

+1 with the price point Honda already at with the VFR1200 in current form they probably didn't want to add more R&D cost to install a traction control system so the above statement for me rings very true "poor mans traction control". To think it was done because the drive train couldn't handle the torque in 1st & 2nd gear would mean there would be a potential for it to fail in any other gear which is crazy because in the end the available tyre grip is what will fail first. There is also the thought that maybe it was done for emissions & noise due to lower gears for a given speed the revs are higher, who really knows because your never going to get an official word from Honda. It is simply a strange thing to do to limit lower gears because some riders don't know how to use throttle control & maybe they only did it due to the target market as they don't do it to there full blown sportsbikes unless to abide by a particular countries regulations but that happens through all gears.

I applaud how there are people that always find solutions, I just would like a solution that means I can have the gear indicator still work 1st & 2nd now Honda have finally fitted something I always fit to my motorbikes.

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First off...congrats to dutchgixxer for being what appears, on the verge of solving the lower gear power limitation. But would someone help me out here? I may have missed it but in all the reading of posts, I have not seen it addressed why the VFR1200 was detuned in the first place. Somewhere....in Japan...around some engineering table, the decision was made to do this. On a bike that is already at or beyond the maximum consumer price point, why did they elect for the added production costs of the sensors and what-not for this detuning? Was it to make the rear tire last longer? Was it to keep the front wheel on the ground? Was it to keep the rear passenger on the seat? Was it to prevent over-torqueing the shaft drive system? Somewhere out there is THE valid reason this was settled upon in that engineering room. I'm like everyone else in that there is a never ending desire for more power but before I snipped or jumpered anything on my brand new bike, I would have to understand what was on the minds of the people that built it that way. I understand rev limiters and I understand max speed cutouts designed in some bikes but this detuning in those lower gears is for some other reason. Please anyone/everyone give me your best guess as to what the reasoning might be. Thanks in advance.

I happened to read the test of the DCT in the current issue of Sport Rider in the store the other day. The commentary (I would assume this was the message from Honda) was that in the DCT the dual clutch basket is not quite as robust as that of a single clutch. Kinda makes sense since they are essentially stacked on top and concentric as well. The added 2 inches of width means the huge forces it must transmit are extended farther outbound on the coaxial shafts and clutch basket fingers, my intuition suggests it would not be as structurally sound as a thinner, more compact basket mounted on a solid shaft. This is not to say the structure is weak, but every component no matter how strong still has it's breaking point. Honda being traditionally conservative probably chose to err on the side of restraint and added reliability over all out performance.

That said, it does not explain why the same crippling in the first 2 gears is present on the standard clutch model which does not suffer the same mechanical concerns unique to the DCT. It could be that for the first year out they want to be conservative with both models to gain some real world reliability data, and perhaps dial back the degree of restraint in subsequent releases. Dunno why, but you have a good point that Honda (and virtually all companies) certainly has their rationale for the engineering decisions they make. The last thing any manufacturer wants is a massive design flaw that will cost them millions to fix. Just ask Aprilia about their RSV4 woes.

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Did you see that youtube video of the kid that throws down his brand new gixxer as he guns it out of the dealership? Rear wheel just spins out like the tire was made out of plastic! Then down she goes...

I saw a video of the VFR1200 being driven by a journalist at a japanese track way back at the initial release and he spun out the rear wheel...saved it, but still... I have a feeling 'if you don't know what your doing' the torque at the rear wheel will bite you in 1st or 2nd gear in this new VFR1200, so Honda played it safe. That's all they needed, all kinds of stories about it being a 'dangerous' bike. I think that is why is has been restricted...poor man's traction control.

Brian

I think you hit the nail on its head. :biggrin:

Edited by Dutchgixxer

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Did you see that youtube video of the kid that throws down his brand new gixxer as he guns it out of the dealership? Rear wheel just spins out like the tire was made out of plastic! Then down she goes...

I saw a video of the VFR1200 being driven by a journalist at a japanese track way back at the initial release and he spun out the rear wheel...saved it, but still... I have a feeling 'if you don't know what your doing' the torque at the rear wheel will bite you in 1st or 2nd gear in this new VFR1200, so Honda played it safe. That's all they needed, all kinds of stories about it being a 'dangerous' bike. I think that is why is has been restricted...poor man's traction control.

Brian

I think you hit the nail on its head. :biggrin:

I have chanced the scematic a bit. I have made de de restriction switchable. Some testing learned that when using sports tires ( i do ) in cold weather or in the wet its very easy to spin the rear wheel.

Phobe had alterted the wiring near the ecu. I have made the mod near the GPSensors connector. Its just a choise

post-20539-081796300 1287037092_thumb.jp

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Did you see that youtube video of the kid that throws down his brand new gixxer as he guns it out of the dealership? Rear wheel just spins out like the tire was made out of plastic! Then down she goes...

I saw a video of the VFR1200 being driven by a journalist at a japanese track way back at the initial release and he spun out the rear wheel...saved it, but still... I have a feeling 'if you don't know what your doing' the torque at the rear wheel will bite you in 1st or 2nd gear in this new VFR1200, so Honda played it safe. That's all they needed, all kinds of stories about it being a 'dangerous' bike. I think that is why is has been restricted...poor man's traction control.

Brian

I think you hit the nail on its head. :biggrin:

I have chanced the scematic a bit. I have made de de restriction switchable. Some testing learned that when using sports tires ( i do ) in cold weather or in the wet its very easy to spin the rear wheel.

Phobe had alterted the wiring near the ecu. I have made the mod near the GPSensors connector. Its just a choise

post-20539-081796300 1287037092_thumb.jp

:idea3:Which explains why Honda put a restriction on in the first place, really........

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I have chanced the scematic a bit. I have made de de restriction switchable. Some testing learned that when using sports tires ( i do ) in cold weather or in the wet its very easy to spin the rear wheel.

Phobe had alterted the wiring near the ecu. I have made the mod near the GPSensors connector. Its just a choise

post-20539-081796300 1287037092_thumb.jp

Now you have individual switches for 1st and second gear... Good idea I might do the same. It's probably advisable not to flip the switches when the bike is in first or second. Otherwise you could throw a fault code.

edit: a DPDT switch would also work.

Edited by phobe

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I have chanced the scematic a bit. I have made de de restriction switchable. Some testing learned that when using sports tires ( i do ) in cold weather or in the wet its very easy to spin the rear wheel.

Phobe had alterted the wiring near the ecu. I have made the mod near the GPSensors connector. Its just a choise

post-20539-081796300 1287037092_thumb.jp

Now you have individual switches for 1st and second gear... Good idea I might do the same. It's probably advisable not to flip the switches when the bike is in first or second. Otherwise you could throw a fault code.

edit: a DPDT switch would also work.

Please explain what a DPDT switch is.

Thanks

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Did you see that youtube video of the kid that throws down his brand new gixxer as he guns it out of the dealership? Rear wheel just spins out like the tire was made out of plastic! Then down she goes...

To be fair, the bike in that video had brand new, cold tires, which is pretty much like riding on ice if you give it any gas. I also have an '08 GSX-R1000, and believe me, you have to do something very stupid for the bike to get out of shape that badly with the tires in normal operating condition. I once watched an ex-racer dump his ZR-7 (hardly a fire-breathing monster) in the middle of the road after turning out of the parking lot to go home for the day. You just have to be careful...

Whether Honda is trying to save the drivetrain or the rider is anybody's guess at this point, but if I owned the bike, I would definitely want it unrestricted.

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I have chanced the scematic a bit. I have made de de restriction switchable. Some testing learned that when using sports tires ( i do ) in cold weather or in the wet its very easy to spin the rear wheel.

Phobe had alterted the wiring near the ecu. I have made the mod near the GPSensors connector. Its just a choise

post-20539-081796300 1287037092_thumb.jp

Now you have individual switches for 1st and second gear... Good idea I might do the same. It's probably advisable not to flip the switches when the bike is in first or second. Otherwise you could throw a fault code.

edit: a DPDT switch would also work.

Please explain what a DPDT switch is.

Thanks

Double pole, double throw - Equivalent to two SPDT switches controlled by a single mechanism: A is connected to B and D to E, or A is connected to C and D to F.

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Now you have individual switches for 1st and second gear... Good idea I might do the same. It's probably advisable not to flip the switches when the bike is in first or second. Otherwise you could throw a fault code.

edit: a DPDT switch would also work.

Please explain what a DPDT switch is.

Thanks

Double-Pole-Double-Throw On-On switch. Like this one: http://www.thesource.ca/estore/Product.aspx?language=en-CA&catalog=Online&category=Switches+Switches&product=2750636

It is an "on-on" switch with 6 terminals. I think I might repair my harness wiring then install one of these under the seat tied into the wiring near the GPS for switchable power modes.

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Now you have individual switches for 1st and second gear... Good idea I might do the same. It's probably advisable not to flip the switches when the bike is in first or second. Otherwise you could throw a fault code.

edit: a DPDT switch would also work.

Please explain what a DPDT switch is.

Thanks

Double-Pole-Double-Throw On-On switch. Like this one: http://www.thesource.ca/estore/Product.aspx?language=en-CA&catalog=Online&category=Switches+Switches&product=2750636

It is an "on-on" switch with 6 terminals. I think I might repair my harness wiring then install one of these under the seat tied into the wiring near the GPS for switchable power modes.

Thanks for the explanation. I prefer 2 single On-On switches.

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Now you have individual switches for 1st and second gear... Good idea I might do the same. It's probably advisable not to flip the switches when the bike is in first or second. Otherwise you could throw a fault code.

edit: a DPDT switch would also work.

Please explain what a DPDT switch is.

Thanks

Double-Pole-Double-Throw On-On switch. Like this one: http://www.thesource.ca/estore/Product.aspx?language=en-CA&catalog=Online&category=Switches+Switches&product=2750636

It is an "on-on" switch with 6 terminals. I think I might repair my harness wiring then install one of these under the seat tied into the wiring near the GPS for switchable power modes.

Thanks for the explanation. I prefer 2 single On-On switches.

Makes sense, gives you 4 options instead of 2.

Brian

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I went to Radio Shack and bought the switch I linked to in post 19. Here is a crude illustration of how I plan to wire it.

I'll mount the switch under the seat... That will ensure that the bike has to be shut off to throw the switch.

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I went to Radio Shack and bought the switch I linked to in post 19. Here is a crude illustration of how I plan to wire it.

I'll mount the switch under the seat... That will ensure that the bike has to be shut off to throw the switch.

post-18833-088373600 1287085640_thumb.jp

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I went to Radio Shack and bought the switch I linked to in post 19. Here is a crude illustration of how I plan to wire it.

I'll mount the switch under the seat... That will ensure that the bike has to be shut off to throw the switch.

Please, please just ride it as you've done now and relay a ride report... patience is tough for me :comp13:

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I went to Radio Shack and bought the switch I linked to in post 19. Here is a crude illustration of how I plan to wire it.

I'll mount the switch under the seat... That will ensure that the bike has to be shut off to throw the switch.

I think your wiring diagram is false. In the derestriced mode 1st and 2 nd are always connected to the ECU. The ECU sees 2 gears engaged.

The GPS for 1st and 2nd wires have to move to both the middle ( P contact ) poles.

Edited by Dutchgixxer

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