Below is the verified pinout for EFSE ECUs used in Hijet models from 1990–1999. Pin numbering is viewed from the wire side of the connector (harness side), with the clip facing up.
| Pin | Wire Color | Function | Signal Type | Hot Failure Mode | |-----|------------|----------|-------------|-------------------| | 1 | Black/Red | Injector 1 (Cyl #1) | Ground switched (ECU) | Open circuit hot; injector stays closed | | 2 | Black/White | Injector 2 (Cyl #2) | Ground switched | Same as above | | 3 | Black/Yellow | Injector 3 (Cyl #3) | Ground switched | Same as above | | 4 | White/Black | Main Relay Control | Ground output | Relay drops out when hot (no fuel pump, no power to sensors) | | 5 | Yellow | Check Engine Light | Ground output (lamp driver) | Dim or flickering when hot | | 6 | Blue/Red | Tachometer Output | 12V square wave | Signal drops at high temps | | 7 | Black | Switched 12V (main power) | Power input | Voltage drop when hot due to corroded fuse | | 8 | Red/Black | Battery 12V (backup) | Constant power | Keeps adaptives; no start if hot? Check fuse. | | 9 | Green/White | Engine Ground (sensor return) | Sensor ground | Leakage causes MAP/TPS drift hot | | 10 | Brown/Yellow | MAP Sensor Signal | 0-5V analog | Voltage drives low when heat-soaked | | 11 | White/Green | TPS Signal | 0-5V analog | Intermittent dropouts hot | | 12 | Green/Red | Intake Air Temp | 0-5V (thermistor) | Resistance changes abnormally hot | | 13 | Blue/White | Coolant Temp | 0-5V (thermistor) | Critical: reads low when hot, causing rich running | | 14 | Green | O2 Sensor (if equipped) | 0-1V narrowband | Slow response hot | | 15 | Black/Blue | Ignition Timing Control (IGT) | 5V digital | ECU stops sending timing signal hot | | 16 | White/Red | Ignition Confirmation (IGF) | 5V feedback | ECU sees no IGF, cuts fuel hot | | 17 | Orange | Starter Signal (STA) | 12V input | Cranking only; no effect hot unless shorted | | 18 | Red/White | Neutral Safety Switch | Ground or 12V | Not critical hot | | 19 | Black/Red | Injector 1 (duplicate ground) | Same as pin 1 | Redundant path | | 20 | Black/White | Injector 2 (duplicate) | Same as pin 2 | Redundant | | 21 | Black/Yellow | Injector 3 (duplicate) | Same as pin 3 | Redundant | | 22 | Blue/Black | ISC Valve (Idle Speed Control) | Coil driver | Sticky when hot; idle surge | | 23 | Yellow/Black | Fuel Pump Relay | Ground output | Intermittent hot = no fuel pressure | | 24 | Brown | Power Ground (E01) | High current ground | Most critical hot – voltage drift here kills ECU | | 25 | Brown/White | Power Ground (E02) | High current ground | Same as above – must be <0.1Ω to battery | | 26 | Red | 5V Sensor Reference Out | 5V supply | Drops below 4.8V hot = all sensors fail | | 27 | Blue/Green | Cam Signal (G1/G2) | AC sinewave/Hall | Misses sync hot; no start | | 28 | White/Black | Crank Signal (Ne) | AC sinewave | Same as above | | 29 | Not used | – | – | – | | 30 | Green/Yellow | Vehicle Speed Sensor (VSS) | 12V pulse | Not critical hot unless auto trans | | 31 | Black/Green | AC Switch Signal | 12V input | Adds idle-up; no effect hot | | 32 | White/Blue | Power Steering Oil Pressure | 12V input | Idle-up only | | 33 | Black/Orange | Brake Switch | 12V input | – | | 34 | Blue | Diagnostic Terminal (T) | 12V/data | Shorting to ground flashes codes | | 35 | Not used | – | – | – | | 36 | Black/Yellow | ECU Backup Power (battery direct) | Constant 12V | Losing this while hot resets learned values | daihatsu hijet efse ecu pinout hot
Heat is the EFSE ECU’s nemesis. The ECU is often mounted on the firewall or near the heater core. Over time, thermal cycles cause: Below is the verified pinout for EFSE ECUs
When searching for a “hot” pinout, you need to know which pins carry high current and which carry sensitive 5V signals. Heat is the EFSE ECU’s nemesis
Keep this printed in your glovebox:
| Symptom (Hot) | Check Pin(s) | Expected Hot Value | |------------------|----------------|------------------------| | No fuel pump prime | 4 (Main relay), 23 (Fuel pump) | Ground (0V) during crank | | Cranks, no spark | 15 (IGT), 16 (IGF) | 5V pulses | | Runs rich, black smoke | 13 (Coolant), 10 (MAP) | C Temp: <1V, MAP: 1.5V idle | | No 5V to sensors | 26 (Ref), 9 (Return) | 5V ±0.15V | | Erratic tach | 6 (Tach out) | ~6V square wave | | Intermittent dying | 24, 25 (Power grounds) | <0.1V drop to battery |