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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- Powertrain/On-Board Diagnostic System Check

Diagnostic Chart:




Diagnostic Flow Diagram:






The PFI system check should be the starting point for all diagnosis of the Powertrain Control System. It will direct you to the appropriate performance test.

If you are reasonably certain that the problem is powertrain related, the best place to start is with the PFI SYSTEM CHECK.

If you are unsure whether the problem is powertrain related, you may want to start with the DIAGNOSTIC CIRCUIT CHECK.