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Gear indicator display

oxford1327
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oxford1327 Experienced

oxford1327

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Has anybody successfully worked out how to have an aftermarket gear position indicator for an auto in a stagea?

With the Link dash installation almost complete were having issues getting the gear position to show on dash unit, as the factory dash uses 2 seperate signal types between the box and the ECU, as in it receives a square wave signal and transmits a sine wave or vice versa, so it's not reading and allowing the dash panel to show .

It will also be making it potentially worse being that the trans is a manualised valve body and being Jatco 4th gear is electrically selected as well as the lock-up for converter, so they are switched seperate 

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oxford1327 Experienced

oxford1327

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On 6/6/2022 at 8:05 PM, GTSBoy said:

Just do it calculated off of vehicle speed vs RPM.

We can potentially do that, but what about indication for neutral, reverse,park and converter lock up? And would also like to avoid any more thousands in labour costs for calculating and calibration, am reaching out to Link and Aim(dash manufacturers) to see if they have a work around,but thought there may have been someone that's seen it done in a track,drift or drag car that has a Jatco box???

RBW49N Community Regular

RBW49N

Posted
Posted
On 6/6/2022 at 5:48 PM, oxford1327 said:

Has anybody successfully worked out how to have an aftermarket gear position indicator for an auto in a stagea?

With the Link dash installation almost complete were having issues getting the gear position to show on dash unit, as the factory dash uses 2 seperate signal types between the box and the ECU, as in it receives a square wave signal and transmits a sine wave or vice versa, so it's not reading and allowing the dash panel to show .

It will also be making it potentially worse being that the trans is a manualised valve body and being Jatco 4th gear is electrically selected as well as the lock-up for converter, so they are switched seperate 

I can look into the wiring tomorrow and see where it picks up the signal if you want

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GTSBoy Grand Master

GTSBoy

Posted
Posted
On 6/6/2022 at 6:58 PM, oxford1327 said:

neutral, reverse,park

There are switches for those, no?

TC lockup could possibly be inferred from rpm vs speed also. If it sits dead bang on the relationship given by the gearing, then TC is locked up. If it is in the "band" available from TC slip around the gear ratio, then it is unlocked.

oxford1327 Experienced

oxford1327

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On 6/6/2022 at 11:44 PM, GTSBoy said:

There are switches for those, no?

TC lockup could possibly be inferred from rpm vs speed also. If it sits dead bang on the relationship given by the gearing, then TC is locked up. If it is in the "band" available from TC slip around the gear ratio, then it is unlocked.

Yep there are 2 manual switches for 4th gear and lock up, so they're the easiest to solve I spose in comparison, just a bugger that the Link ecu and the Link dash can't bloody read the gear position by themselves, and seems that I'm always the damn guinea pig too, but that's my fault for wanting pretty /shiny things and jumping first....

robbo_rb180 Grand Master

robbo_rb180

Posted
Posted

I have replied in other thread, this is so easy to do and isn't thousands to setup by a competent workshop/tuner.
Its all in what is wired to ecu and in its setup so many people have no idea how to do it right.

joshuaho96 Veteran

joshuaho96

Posted
Posted
On 6/6/2022 at 6:44 AM, GTSBoy said:

There are switches for those, no?

TC lockup could possibly be inferred from rpm vs speed also. If it sits dead bang on the relationship given by the gearing, then TC is locked up. If it is in the "band" available from TC slip around the gear ratio, then it is unlocked.

Can't you snoop the TC lockup solenoid to determine this too?

oxford1327 Experienced

oxford1327

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  • Author
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On 6/8/2022 at 7:57 AM, joshuaho96 said:

Can't you snoop the TC lockup solenoid to determine this too?

Honestly have no idea with anything that has wires cos I tend to let the smoke out of them, so I leave that stuff to others and stick to mechanical things that I can see what they do and how.....

zoomzoom Mentor

zoomzoom

Posted
Posted

The 2 shift solenoids form a 2-bit number which describe the forward gears. But don't assume, 0 is first first gear, and 3 is 4th gear. I think from memory b00 is actually 3rd.  The ECU loom also has wires which are digital states for when central shifter is in reverse, neutral or the forward gears.

Coupled with some microcontroller logic (or lucky you if your ECU is modern and has some flexible inbuilt programmable logic), you could determine what gear is currently active, and drive an LED digit display.

Forget the speed vs rpm method for an auto.

P.S.

From one of my micro programs the solenoid combos are as follow (LSB being solenoid 1)

b00 : 3rd gear
b10 : 2nd
b01 : 4th
b11 : 1st

oxford1327 Experienced

oxford1327

Posted
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On 6/9/2022 at 2:47 PM, zoomzoom said:

The 2 shift solenoids form a 2-bit number which describe the forward gears. But don't assume, 0 is first first gear, and 3 is 4th gear. I think from memory b00 is actually 3rd.  The ECU loom also has wires which are digital states for when central shifter is in reverse, neutral or the forward gears.

Coupled with some microcontroller logic (or lucky you if your ECU is modern and has some flexible inbuilt programmable logic), you could determine what gear is currently active, and drive an LED digit display.

Forget the speed vs rpm method for an auto.

P.S.

From one of my micro programs the solenoid combos are as follow (LSB being solenoid 1)

b00 : 3rd gear
b10 : 2nd
b01 : 4th
b11 : 1st

Cheers, will look into this 

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