This is a KiCad project for a simple ISO-9141 interface board. This allows a microcontroller to be interfaced to car's ISO-9141 (OBD2) port.
Please see related firmware projects:
Here is the official ISO standard document that explains all of the details of this interface. What makes this interesting is that the transmit/receive to/from the vehicle all happens on a single wire.
Send any questions to bruce at mackinnon dot com.
J1 is the connection to the vehicle:
- Pin 1 - 12V battery power
- Pin 2 - KLINE
- Pin 3 - Ground
J2 is the connector to the microcontroller:
- Pin 1 - Data transmit (data from controller to vehicle)
- Pin 2 - Data receive (data from vehicle to controller)
- Pin 3 - Control line which allow the KLINE to be pulled low for the purposes of signalling
- Pin 4 - An indicator LED that can be used by the controller
- Pin 5 - +5V regulated power for controller
- Pin 6 - Ground
The V2 PCB:
Here's what it looks like in real life (V1):
The scanner/instrument uses a SAE J1962 connector (male)
The vehicle uses a J1962F female connector like this: https://www.amazon.com/Goliton-Connection-Connector-Harness-Assembled/dp/B09NBWQLMQ
Copyright (C) 2024 - Bruce MacKinnon
This work is covered under the terms of the GNU Public License (V3). Please consult the LICENSE file for more information.
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