Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Expanded Diagnostic Protocols Table


Expanded Diagnostic Protocol Table (Part 1 Of 2):





Expanded Diagnostic Protocol Table (Part 2 Of 2):






The table lists the string of characters entered in a generic scan tool when accessing the enhanced diagnostic PID information that may not be common on all OBD II vehicles.


NOTE: A formula may need to be performed on an Expanded Diagnostic Protocol PID for displaying a value in volts.

Formula Chart:






Example: 32000 Counts divided by 13107 = 2.44 Volts (scaled from 0 to 5)