jonsole/toyotune8Daughter-board for reprogramming 1990's Toyota ECUs
Carrier is an open-source printed circuit board by jonsole, from the jonsole/toyotune repository on GitHub, published under the GPL-3.0 licence. It is a 4-layer board of 55 × 35 mm with 30 parts on 17 nets, routed with 45 tracks and 14 vias.
It is built around the TJA1051T/3, 24LC256-I/P and IRLML6402, with the PESD2CAN, SMBJ26A and SS34 among its other parts. Its parts include 8 capacitors, 6 resistors, 4 diodes, 3 ICs and 3 connectors.
Reverse engineering and ROM tuning for Toyota ECUs built on the Toshiba/Denso 8X (D8X) microcontroller — a proprietary part with an instruction set derived from the Motorola 68HC11.
The best entry point is Inside the 3S-GTE ECU, an architectural tour of the 1993 SW20 MR2 turbo ECU: three processors, adaptive fuel trim and per-cylinder knock learning in 16 KB of ROM.
roms/ — disassembly, annotation and tuned-ROM production.
One directory per engine family (1G-GTE, 1G-GZE, 1JZ-GTE, 1UZ-FE, 3S-GE,
3S-GTE, 3VZ-FE, 4A-GE), each holding one subdirectory per ECU part number.
roms/3S-GTE/ is the most thoroughly documented family —
its README maps every part number to market,
vehicle and CPU, and gen3/ holds the subsystem
write-ups.roms/docs/ documents the D8X MCU itself — instruction
set, opcode matrix, registers — which every family here shares.roms/d8x_assembler/ is a Python reimplementation
of the D8X assembler, and what the Makefiles actually build with.hw/ — the Toyotune interface board: PCB, CPLD and host-MCU
firmware for reading and rewriting these ECUs, including live access while
the engine is running.sw/ — IDA Pro installs used to open the .idb databases.Ongoing and incomplete. The 3S-GTE Gen 3 pair is the furthest along; other families are largely raw disassembly. Coverage is stated honestly in each document — see session_journal.md for what is done and what is pending.
| Qty | Value | Footprint | References |
|---|---|---|---|
| 4 | 100n | Capacitor_SMD:C_0603_1608Metric | C3, C5, C6, C9 |
| 4 | M2 | MountingHole:MountingHole_2.2mm_M2 | H1, H2, H3, H4 |
| 2 | 4k7 | Resistor_SMD:R_0603_1608Metric | R5, R6 |
| 2 | 60R4 | Resistor_SMD:R_0805_2012Metric | R3, R4 |
| 1 | 100k | Resistor_SMD:R_0805_2012Metric | R2 |
| 1 | 10u | Capacitor_SMD:C_0805_2012Metric | C2 |
| 1 | 10u/50V | Capacitor_SMD:C_1206_3216Metric | C1 |
| 1 | 12V | Diode_SMD:D_SOD-123 | D5 |
| 1 | 1A | Fuse:Fuse_1206_3216Metric | F1 |
| 1 | 1k | Resistor_SMD:R_0603_1608Metric | R1 |
| 1 | 24LC256 | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U3 |
| 1 | 470u/10V | Capacitor_SMD:CP_Elec_8x10.5 | C4 |
| 1 | 4n7 | Capacitor_SMD:C_0603_1608Metric | C7 |
| 1 | IRLML6402 | Package_TO_SOT_SMD:SOT-23 | Q1 |
| 1 | Loom in | Connector_Molex:Molex_Micro-Fit_3.0_43045-0400_2x02_P3.00mm_Horizontal | J2 |
| 1 | Loom out | Connector_Molex:Molex_Micro-Fit_3.0_43045-0400_2x02_P3.00mm_Horizontal | J3 |
| 1 | PESD2CAN | Package_TO_SOT_SMD:SOT-23 | D3 |
| 1 | SMBJ26A | Diode_SMD:D_SMB | D1 |
| 1 | SS34 | Diode_SMD:D_SMA | D2 |
| 1 | TJA1051T/3 | Package_SO:SOIC-8_3.9x4.9mm_P1.27mm | U2 |
| 1 | TSR 1-2450 | Converter_DCDC:Converter_DCDC_TRACO_TSR-1_THT | U1 |
| 1 | To display module | Connector_PinSocket_2.54mm:PinSocket_1x08_P2.54mm_Vertical | J1 |
It measures 55 × 35 mm and has 4 copper layers, 1.6 mm thick.
30 parts, built around the TJA1051T/3, 24LC256-I/P, IRLML6402 and PESD2CAN. The full list of its parts is on this page, with links to each part's symbol and footprint where PCBKit's library has them.
From the jonsole/toyotune repository on GitHub, at the commit this page was made from: the board is hw/dash_cluster/carrier/carrier.kicad_pcb and its schematic hw/dash_cluster/carrier/carrier.kicad_sch. PCBKit opens the board in the browser, with nothing to install.
Its repository publishes it under the GPL-3.0 licence: you may reuse it on that licence's terms (keep the author's notice, and for a copyleft licence share your changes alike).
dhruxraj/stm32-can-ecu
A compact, "ECU-style" CAN node for learning and prototyping automotive-type embedded software. It has an STM32G4 MCU, a CAN transceiver with protection and switchable termination, a 6-axis IMU, a protected 8-18 V…
nathanfraske/CEC-Platform
ONE board file, kept current by the wave (owner directive 2026-07-25: "the current best should be placed into a candidate folder per board and kept current with only one board ideally so we have a reference").
DerNiccoo/WLED-PCB-Designs
Collection of my WLED PCB Controllers and Boards
haya1010/esp32-c3-safe-dip-led-controller
Protected ESP32-C3 2.54 mm DIP controller with USB-C and 3-channel 5/12/24 V LED PWM outputs
Lnotti/5-Channel-High-Current-Li-po-Discharger
A PCB designed to discharge 6S LiHV battery packs to storage voltage (3.8V per cell / 22.8V total) across up to 5 independent channels simultaneously.
pyshrekek/ufluidics
Firmware for an Elegoo Mega 2560 R3 driving five NEMA17 syringe pumps on a microfluidic device.
DevKiDCosmo/SATELLITE-EDGE-MODULE
A satellite edge module ready for competition