A Prius ECT Spoofer MCU Controlled

Being snowbound for a while I have built up 3 prototypes that use a PIC to drive them.
1, Based on a PIC low pin count demo board
2, A custom SD sized board
3, A SlaGe based unit with switches and a 3 digit LCD to provide adjustability to the temperature trip points

I have NOT hooked it up to my 08 Gen II Prius yet to see how well it works but I have sampled sensors such as ECT, ACT, TOT, MLPS o2 and added Oil Pressure, DFPressure on the Ford EEC-V for a number of years in a 97 TBird and a 02 GT in additon to tapping into the Intel MBUS.

Assembly code continues to be written and I think that it should work fine.
Pics are hosted here







Winston.

 

It Works

I made changes to the Assembly Code in the Prius ECT Spoofer to improve the accuracy of the LCD readout which will now display the coolant temperature at all times.

When the car is warming up it wll start spoofing when the temperature exceeds 112 deg F showing 166 deg F when the actual temperature is between 112 and 166. At 166 it will quit spoofing and pass on the actual temperature to the ECU.

Cooling down from above 166 deg it wll trip on at 166 and display 166 all the way down to the lower trip out point. The Firmware will trip out at 3-4 degrees lower around 108. Four degrees of hysteresis were added to remove the possibility of 'hunting' at the lower trip point.

Once the Spoofer has started spoofing, the temperature displayed on the Scangauge is the spoofed value the actual value is only known to the 'spoofer' hardware which now uses a table lookup algo to convert the A2D reading to deg F and display it on its LCD.

The LCD and the switches add the ability to change the trip points without needing a full re-flash, the Spoofer has code which enables it to change and save the trip points on the fly.

Winston.

 

A marketing case has yet to be made for this project.
I did pick a technology and thereby components to keep the costs as low as the present day technology would permit.
In this scenario the major cost omitted in these projects is my time to capture it on Orcad Schematic Capture , buy parts, build proof of concept units under a microscope (takes hrs), write the code in Assembly, run it thru the Simulator and debug on the bench and later in the car.
My tax accountant has said that my project expenses up to this point are not deductable as they were incurred as a result of 'hobby' activities.

El Presidente where are you when inventors need materiel?

winston

 

Yes the working principle is similar.
I use a PIC16f914 on a custom card in order to drive the LCD, with the appropriate code this enables me to vary the trip points and observe the engine temp when spoofing is active.
The Firmware could be markedly different as a number of routines that I wrote in 2006, had to be pulled in from my sw library to make it work.
The output driver that I use is different.

winston.

 

Some Sections of this project can be open sourced as far as I can tell.

There are a number of things tobe workedout to make this device ready to be open sourced.

The Firmware utilizes some routines that I wish to keep out of public view as I use them in an earlier project which has not made it to market yet because of cost over-runs.

The hardware needs PCB artwork generated and a panel of of say 5x10 PCBs etched, these will have to be sold to cover the payment to the PCB layout guy and the board fab house, DigiKey parts cost is another factor as the PCBs should be sold fully assembled, programmed and tested.

I cannot advise you to continue or not continue with your project.

Would you like to Beta test the MCU ECT Spoofer ? Before you answer a NDA may be required.

winston.

 

I am not looking forward to making another of the SDHC as my eyesight is fading (a combonation of being long in the electronics and laser switching bussines) also and this is why I am thinking of having a number of PCBs etched.

The SDHC version does not have enough pins to drive the LCD display or read the push botton switches to change the trip points but it does have LED indicators to indicate the temperature range of the coolant.

The open-souce Arduino approach is not totally free as you will have to buy the particular Arduino Card plus buy/build another card to carry the driver components. The Atmel Mega/ Arduino Compiler/ is probably free, Source Code and Hex file would be free the for the Arduino Spoofer hence the 'open-source'.

winston.

 

$50 that much !!. But wait I paid $13 for single pin wire pigtail of a ECU connector for the EV hack.

The SDHC version (without the LCD ) with buying parts at 1K pricing range and not providing the SDHC case I think should have a retail price of less than $20 if we can buy the blank PCBs at a 'resonable' price.

To reduce the PCB area to drop the costs even further I was thinking of going to the leadless DFN type of package and seeing if the ECT driver can be changed to a NCh FET and a resistor.
A Micro SD sized card is feasble then but you can always build the circuit up using DIP sized parts on a protoboard.

My efforts this past 2 days has been to test the SDHC version that does not use that routine from my SW Lib and so could be more ameniable to Open Sourcing the Firmware, the schematic and the BOM.
As I will have to pay to get the board laid out the phototool files may not be released as part of that package. I have looked at free autoroute package available on line but it seems that the parts that I use are not in the libraries and I will have to create the footprints for the parts that I use.

winston.

 

The LCD that the Spoofer uses is a simple 3 digit 7 segment 'GLASS' device probably costing around $3. Those serial LCD displays are not cheap. The Noritake Itron VFD is a great looking display but it is even more expensive.

I dont think that the SDHC version should be sold for more than $20 at 100 pcs to defray my direct costs
The LCD version with its LCD, larger processor (more pins to drive the LCD ), and pushbuttons maybe $30

I am currently hacking into my 02 Mustang GT, that uses a MDE2 catch code EEC-V, and I think that it could use this device in addition to code timer changes that I can make to shorten the warm up times which will save the planet a little by saving a few teaspoons of gas.

Will reply to your PM soon.

winston.