TPS PF4C characteristic curve equation

[68C]

I feel like the man finding his way in a cave with a candle when in comes this guy with a generator backpack and a bunch of LED floodlights.

 

Amazing.

[MartyNZ]

Hi Martin,do you know that CTS is the supplier of Magneti Marelli? I won't fish in the dark.

 

Beard (author of the GuzziDiag suite) made an interesting proposal. Which is to use the PF1C. Because it doesn't have the oval holes necessary for rotation, he would modify the contents of the EEPROM and add an offset. And we could adapt the TPS lookup table to the linear curve of it.

The PF1C is available for ~11$ from Alibaba, so I went ahead and ordered one.

 

Cheers

Meinolf

Luhbo claims that the Marelli TPS is made by CTS. http://www.v11lemans.com/forums/index.php?showtopic=8805#entry99551.. CTS claim to be a leading manufacturer of automotive sensors. I don't know any more than that.

 

Kiwi Roy mentioned a Hall Effect TPS replacement, which is likely to be more durable, and tolerant of bad weather than a sliding resistor. Would it be more worthwhile to develop an EEPROM variant for a Hall sensor instead of a PF3C? http://www.v11lemans.com/forums/index.php?showtopic=19647&page=3&do=findComment&comment=217258

[Meinolf]

Hi Martin,

 

Hubert knows what he's talking about. I'll send an inquiry to CTS.

 

Roy and I had an exchange about the the Hall effect sensor some time ago, but I didn't follow it up. Roy, did you?

 

Cheers

Meinolf

[Meinolf]

Hi,

 

a short update. 

 

Concerning the PF4C, 

Finland comes to the rescue. MotoMatti (https://translate.google.de/translate?hl=en&sl=fi&u=http://www.motomatti.fi/&prev=search)  built a contraption to measure angle and voltage. A friend will send him a PF4C, so eventually we will have the curve of the PF4C equation.

Jeff, the CEO of CA Cycleworks, replied to my inquiry. Unfortunately he hasn*t measured a PF4C.

 

And, more great news. Beard (the wizard who programmed GuzziDiag) found out which which addresses of the EEPROM need to be changed to adopt a PF1C (that's the TPS with a known linear curve but holes instead of oval openings). I ordered a PF1C on Alibaba (11$ incl. shipping) and will test it on my ECU bench upon arrival. And the TPS lookup table can be taken from most 15RC BINs, as the PF1C is the OEM TPS.

 

So, all is well

 

Cheers

Meinolf

[Camn]

TPS lookup table can be taken from most 15RC BINs, as the PF1C is the OEM TPS

At first I was: ”but all the V11:s have PF3C” – what does he mean, Meinolf if somebody, should know better...

 

But after checking from GuzziDiag -files => of course there are some models, where there is the 15RC ecu and PF1C tps combined (Breva 750, Nevada Classic 750, Nevada Classic 750 S.E, Nevada 750 S, V7 Classic, V7 Cafè, and early V7 Racer) - he takes the look up table from a BIN -file of one of these... clever.

 

which addresses of the EEPROM need to be changed

If I understand this right, this will be really cool.  Since the PF1C does not have oval screw holes, it cannot be adjusted => how to reach the basic setting of 156 mV (the right value according Meinolf )?  There will be a way to tell with GuzziDiag to the ecu => "now, with this mV tps value, the throttle flap is on the zero opening position (not idle position)".

 

But if you have sandard maps on your ecu, how do you find the idle position after this...(for example 465mV for ”no kat” models or 550mV for ”kat” models) when GuzziDiag (ecu) cannot dispaly values accurate enough for this ?

[docc]

It seems this procedure will require the physical setting of the optimum throttle plate angles before indexing the TPS to the map as on the W5AM system?

[Meinolf]

Hi,

 

a short update.

 

I haven't yet received the PF1C I ordered from AliBaba, but Beard already programmed a patch to the 537-BIN which I tested on my ECU test bed over the weekend. He's added code to the BIN which uses an offset to the ADC-values, which are stored in an unused address of the EEPROM. And it, after ironing out a small bug, works. So the proof of concept is done.

 

The basic idea is to use the offset value stored in the EEPROM value, ranging from -127 to +128, to base-line the actual voltage delivered by the PF1C at a given setting to the TPS look-up table. We are still mulling over the setup procedure, though. After receiving the PF1C I'll attach it to a throttle body and see which setup procedure works and is easy to use. The current idea is to measure V_Actual - V_Target at completely closed throttle and divide the difference by the steps of the 8bit ADC, 0.0196V. The result would be the offset used in the EEPROM value to align the TPS and the look-up table.

 

Cheers

Meinolf

[mikehaven]

its on he site under technical tps