Simos 33a Pinout Top [hot]

The Simos 3.3A (and its variant 3.3) engine control unit (ECU) was widely used in Volkswagen and SEAT vehicles, particularly for the 1.6L 74kW engine (codes AEH, AKL, APF, AUR) around the early 2000s. Core Pinout Information

: Numbers usually proceed sequentially along a row before moving to the next. Key Identification Points Main Power (+12V) : Often found on specific pins like Terminal 30 for constant power and Terminal 15 for ignition-switched power. Ground (GND) : Common ground connections are often labeled as Terminal 31 Communication simos 33a pinout top

5. Important Practical Notes

• No onboard immobilizer control on the top connector – Immobilizer functions (if present) are on the lower (C) connector via K-line.
• Waste-spark ignition: The SIMOS 33A typically uses a double-ended coil pack (two coils firing two plugs each). Pins 16 & 17 control it directly (no external ignition module).
• MAP vs. MAF: SIMOS 33A is speed-density (MAP + IAT), not MAF-based. No MAF sensor.
• Injector wiring: All injectors share a common +12V (from fuel pump relay) and are ground-switched by the ECU via pins 11, 12, 23, 24.
• No transmission control: Automatic transmission is a separate TCU; the ECU only receives signals (e.g., load reduction).

For detailed wiring diagrams including sensor colors and relay locations, the VW ElsaWin software The Simos 3

• VW Golf Mk7 / Touran
• Audi A3 8V
• Skoda Octavia III
• SEAT Leon 5F

is designated for the signal from the second petrol injector. Sensor Inputs G28 Engine Speed Sender : Crucial for determining RPM and ignition timing. Knock Sensors No onboard immobilizer control on the top connector