Shift Cut Issues, Help A Numpty !

This section is dedicated to discussion of DTA engine control units such as the DTA E48 EXP, P8 Pro, DTA S40, S60, S80, and S100, as well as all things ECU related.
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Steve Tilburn
Posts: 13
Joined: Thu Dec 30, 2021 7:09 am
ECU Model: S60 Pro
Distributor: Direct from DTA
Firmware Version: 86.2

Shift Cut Issues, Help A Numpty !

Post by Steve Tilburn »

Hi All,
I have been using a single output hall effect pot with my 5 speed Tractive and S60 Pro with fair results, the pot feeds the gear position indicator and the ECU and I have been using pot to cut and pot to end shift, this has been OK for several years although it occasionally gives me a slight unwanted shift delay usually when short shifting in higher gears but I have also had a few sensor failures in the last few years.
Somebody advised me that the "split" single pot is not ideal and can cause issues, and suggested fitting a twin output sensor using one output for the gear position sensor and the other for the ecu to avoid interference.
So I have fitted a twin output pot and separated the wiring, the first interesting thing was that when I plugged in the gear position sensor, before tackling the ECU connection, the gear position sensor read backwards! I simply swapped the pot outputs and that rectified the issue but I guessed it would cause fun with the ECU later!
The second feed was wired as instructed with a 5v ECU output to the red, earth to black and white wire to the ECU shift cut pin, when connected, as expected the voltages were the wrong way round with high in reverse and lowering as I went through the gears, I thought it would be as simple as swapping the red and black wires assuming the pot wiring was wrong, but this just gave me a continual 5v reading, so I changed them back, then I selected the "Reverse Voltage" setting in flatshift settings which had no effect?
Please somebody put a dipstick right!
Alex DTA
Posts: 1622
Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Shift Cut Issues, Help A Numpty !

Post by Alex DTA »

Reverse Voltage should work as you expect.
Did you press F4 to send the changes to the ECU?
Steve Tilburn
Posts: 13
Joined: Thu Dec 30, 2021 7:09 am
ECU Model: S60 Pro
Distributor: Direct from DTA
Firmware Version: 86.2

Re: Shift Cut Issues, Help A Numpty !

Post by Steve Tilburn »

Hi Alex,
NO!
So should I tick Reverse Voltage then F4 ? I knew it might be my ignorance as usual!
Why did the swapping of the live and earth not work?
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Shift Cut Issues, Help A Numpty !

Post by Rob Stevens »

The hall sensors only work one way round, they are an electronic device, it is not like a passive potentiometer where it would work
Steve Tilburn
Posts: 13
Joined: Thu Dec 30, 2021 7:09 am
ECU Model: S60 Pro
Distributor: Direct from DTA
Firmware Version: 86.2

Re: Shift Cut Issues, Help A Numpty !

Post by Steve Tilburn »

Cheers Rob, so why are the two outputs different from the same sensor?, presumably it's common hence the Reverse Voltage option?
And Do I have to use F4 to enable?
I am rubbish at this stuff!
Steve Tilburn
Posts: 13
Joined: Thu Dec 30, 2021 7:09 am
ECU Model: S60 Pro
Distributor: Direct from DTA
Firmware Version: 86.2

Re: Shift Cut Issues, Help A Numpty !

Post by Steve Tilburn »

Just pushed F4 and voltage reversed nicely, what a Numpty Eh!
Still don't really know what I'm doing though!
Gadgetman
Posts: 34
Joined: Sat Sep 03, 2011 9:29 am
ECU Model: S80 Pro

Re: Shift Cut Issues, Help A Numpty !

Post by Gadgetman »

F4 is the keyboard command that sends what ever change you've made in the software to the ecu itself, until you press F4, the ecu isn't updated.
Steve Tilburn
Posts: 13
Joined: Thu Dec 30, 2021 7:09 am
ECU Model: S60 Pro
Distributor: Direct from DTA
Firmware Version: 86.2

Re: Shift Cut Issues, Help A Numpty !

Post by Steve Tilburn »

What a doughnut I am!
Many thanks for everyone's help should be ok from here, if anyone is local ish to Norfolk it would be great to have someone who knows what they are talking about check my other flatshift settings, happy to pay, would be nice to understand a bit more!
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Shift Cut Issues, Help A Numpty !

Post by Rob Stevens »

Steve
Duel output hall triggers often have output opposing scales.
These sensors are often used in fly by wire control and use both outputs to signal the throttle controller (TC). If one signal gets corrupted due to wiring or sensor fault the TC will go into safe mode. As a further safety feature having one signal operate the other way round gives the TC a chance to spot if the 2 signals have been joined somehow and go into safe mode, if the 2 signals are the same the TC would not be able to spot the fault.
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