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)

Or, hide this message: temporarily or permanently

General Information


Description and Operation Powertrain Control Module (PCM) Description

The Powertrain Control Module (PCM) is designed to maintain exhaust emission levels while maintaining excellent driveability and fuel efficiency. The PCM controls the following operations:

- The fuel control

- The ignition control (IC)

- The knock sensor (KS) system

- The automatic transmission shift functions

- The manual transmission 1-4 Upshift and Reverse Inhibit

- The cruise control enable, it the vehicle has this equipment

- The generator

- The evaporative emission (EVAP) purge

- The A/C clutch control

- The cooling fan control

- The on-board diagnostics for the powertrain functions