Operation CHARM: Car repair manuals for everyone.

Visual Inspection

This inspection will identify modifications or additions to the vehicle operating system that may affect diagnosis. Inspect the vehicle for non-Ford factory add-on devices such as:
- Electronic add-on items:
^ Air conditioning
^ Generator (alternator)
^ Engine turbo
^ Cellular telephone
^ Cruise control
^ CB radio
^ Linear booster
^ Backup alarm signal
^ Computer
- Vehicle modification:

These items, if not installed properly, will affect the Powertrain Control Module (PCM), or transmission function. Pay particular attention to add-on wiring splices in the PCM harness or transmission wiring harness, abnormal tire size, or axle ratio changes.

- Leaks.
- Proper linkage adjustments.