Honda PT3 ECU Technical Reference
Technical reference for the Honda PT3 OBD1 ECU used in 1990-1993 USDM Accord models with the F22A1 SOHC engine.
The PT3 ECU is an OBD1 engine control unit utilized in 1990â1993 USDM Honda Accord models equipped with the F22A1 SOHC non-VTEC engine. This unit shares the same circuit board architecture as the EDM PT5 Accord ECU (board ID: 02D01190-1504).
Board Overview
Hardware Specifications
The PT3 ECU utilizes standard OBD1 architecture. Key components identified in the USDM PT3-A23 manual variant include:
- MCU: OKI 66911
- Logic: 74HC373
- Memory: 38256
Note
The PT3 shares its PCB design with the EDM PT5 variant. Ensure you verify the specific board ID (02D01190-1504) when sourcing replacement components or performing modifications.
ECU Variants and Documentation
| Variant | Application | Details |
|---|---|---|
| PT3-A54 | 1992 Accord LX (Canada) | Automatic Transmission |
| PT3-A23 | 1991 Accord EX (USDM) | Manual Transmission |
Tip
When performing hardware modifications, always reference the specific board revision printed on the PCB to ensure compatibility with existing pinout and component maps.