ELM327P datasheet(51/51 Pages) ELM

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Section Index

Description and Features....................................................................................... 1

Pin Descriptions..................................................................................................... 2

Ordering Information.............................................................................................. 3

Absolute Maximum Ratings....................................................................................4

Electrical Characteristics........................................................................................ 4

Overview................................................................................................................ 5

Communicating with the ELM327...........................................................................5

AT Commands....................................................................................................... 6

AT Command Summary.......................................................................................17

Reading the Battery Voltage................................................................................ 18

OBD Commands.................................................................................................. 19

Talking to the Vehicle........................................................................................... 20

Interpreting Trouble Codes...................................................................................21

Resetting Trouble Codes......................................................................................22

Quick Guide for Reading Trouble Codes............................................................. 22

Bus Initiation.........................................................................................................23

Wakeup Messages...............................................................................................23

Selecting Protocols...............................................................................................24

OBD Message Formats........................................................................................25

Setting the Headers..............................................................................................27

Monitoring the Bus............................................................................................... 30

CAN Messages and Filtering................................................................................31

Multiline Responses............................................................................................. 32

CAN Message Formats........................................................................................ 34

Altering Flow Control Messages...........................................................................35

J1939 Support...................................................................................................... 36

Restoring Order....................................................................................................37

Programmable Parameters.................................................................................. 38

Using Higher RS232 Baud Rates.........................................................................42

Computer Control................................................................................................. 44

Error Messages.................................................................................................... 44

Example Applications........................................................................................... 46

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ELM327

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ELM327P Datasheet(PDF) 51 Page - ELM Electronics