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

Recommended Tools and Equipment

USE
A Digital Multimeter DMM (10 megaohm input impedance) . It can safely be used to diagnose and test most vehicle systems.

DON'T USE
Test lights. They are not recommended due to the possibility of damage to the computer or air-bag circuits.

BE PREPARED
Before attempting to diagnose a circuit for an open or a short, it is important that you:

1. Have the proper reference material available:

^ Power Supply Routings
^ Applicable Wiring Diagrams
^ Troubleshooting Information

2. Understand how the system works.
3. Have a good understanding of what condition you are diagnosing:

^ Situation when the problem occurs. (weather, loads, etc.)
^ What systems interact with the one you are diagnosing?
^ Is it intermittent or a consistent problem?

4. Have proper equipment to perform the diagnosis such as a digital voltmeter, alligator clips, and probe leads.