Patch Overview
This patch modifies a stock ME7.5 2.0L naturally aspirated ECU to:
- Enable Speed Density fueling (MAP/IAT based)
- Provide full closed-loop turbo boost control using the N75 valve
- Disable the MAF sensor entirely (sensor + DTC)
- Integrate VE, Boost Target, and IAT Bias maps
- Route boost control output to the former SAI relay control pin (T121/114)
Map Address Summary
VE Table: 0xF1000, 12x16, 8-bit, VE %
Boost Target Map: 0xF1100, 12x16, 16-bit, millibar ABS, Little-endian
IAT Bias Table: 0xF1200, 1x16, 8-bit, Multiplier (128 = 1.00)
MAP ADC Raw: 0xF0300, 1x, 16-bit, ADC, Little-endian (via MAF input)
IAT ADC Raw: 0xF0310, 1x, 16-bit, ADC, Little-endian
N75 PWM Output: 0xF0200, 1x, 8-bit, PWM duty (0-255)
Custom Logic Location
Custom logic injected at 0xF0000
Includes boost PID, SD load calculation, IAT correction, and N75 control
Required Hardware Modifications
1. MAP Sensor Wiring:
- Connect MAP sensor signal wire to ECU pin T121/43 (former MAF signal)
- Power MAP sensor from 5V and GND lines used by the MAF
2. N75 Valve Wiring:
- Connect N75 valve signal wire to ECU pin T121/114 (former SAI relay control)
- Ensure N75 has switched 12V on the other pin (same as factory)
Note: N75 is ground-switched by the ECU. Signal at T121/114 is PWM from 10 to 95 percent