Simos 33a Pinout Top
For the Siemens (often labeled with part number 06A 906 033 A ) found in VAG vehicles like the Audi A3 1.6i, the "top" or bench pinout is primarily used for reading pincodes, IMMO OFF procedures, or cloning. Simos 3.3A Bench Pinout
For repair or pinout tracing, group logically: simos 33a pinout top
| Pin | Typical Wire Color | Function | Notes / Conditions | |-----|--------------------|-----------------------------------------------|----------------------------------------------| | 1 | Red/Yellow | Permanent battery voltage (ECU main power) | 30a, fused | | 2 | Brown | ECU ground (main chassis ground) | GND, connects to engine block / chassis | | 3 | Black/Yellow | Ignition switched power (15) | Provides +12V when key is in ON/START | | 4 | - | Not connected | | | 5 | - | Not connected | | | 6 | Grey/Red | Throttle position sensor (TPS) – signal | Linear 0-5V output | | 7 | Brown/Green | Intake air temperature (IAT) – sensor ground | Shared sensor ground | | 8 | Yellow/Black | Engine speed sensor (RPM) – signal positive | Variable reluctance sensor | | 9 | Yellow/Blue | Engine speed sensor – signal negative | | | 10 | Blue/Black | Knock sensor – signal | Shielded wire | | 11 | Green | Injector cylinder 3 – control (ground switch) | Low-side output | | 12 | Grey/White | Injector cylinder 1 – control | | | 13 | Green/Yellow | Fuel pump relay control | Activates relay (ground trigger) | | 14 | Green/White | EGR valve (if equipped) – control | PWM output | | 15 | Black/Green | Secondary air injection relay (if equipped) | Ground trigger | | 16 | White/Green | Ignition coil – cylinder 1 & 4 control | Waste-spark ignition (paired) | | 17 | White/Black | Ignition coil – cylinder 2 & 3 control | Waste-spark ignition (paired) | | 18 | Brown/Yellow | Lambda (O2) sensor – heater ground | Shared sensor return | | 19 | White/Yellow | Lambda (O2) sensor – signal (bank 1) | 0-1V narrowband | | 20 | Blue/White | Coolant temperature sensor – signal | NTC sensor, voltage divider | | 21 | - | Not used | | | 22 | Brown/Red | Engine speed sensor – shield / ground | | | 23 | Blue/Grey | Injector cylinder 4 – control | | | 24 | Brown/Black | Injector cylinder 2 – control | | | 25 | Black/Grey | Idle air control (IAC / idle stepper) – coil A| Bipolar stepper motor | | 26 | Brown/White | IAC – coil B | | | 27 | Black/Blue | IAC – coil C | | | 28 | Brown/Red | IAC – coil D | | | 29 | White/Grey | MAP sensor – signal (if speed-density system) | 0-5V output | | 30 | Brown/Blue | MAP sensor – ground | | | 31 | Yellow/Grey | Oxygen sensor heater – control (ground side) | PWM driven | | 32 | Blue/Yellow | Camshaft position sensor (if equipped) – signal| Used for sequential injection (late SIMOS 33A)| For the Siemens (often labeled with part number
Understanding the pinout for the —commonly found in Volkswagen models like the Beetle, Golf, and Polo—is essential for bench programming, diagnostics, or IMMO off procedures. Simos 3.3A ECU Bench Pinout Always verify with your specific wiring diagram
This write-up provides the (60-pin or 64-pin depending on production year), used in majority of SIMOS 33A ECUs. Always verify with your specific wiring diagram.