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

Sample Calculation

The following information is an EXAMPLE ONLY of the Programming Clip Test procedure.

1. The distance is measured from the center of either rear wheel to the ground and found to be 15 inches, so R=15.

2. The axle ratio is found to be 2.73, so A=2.73.

Pulse Per Mile Calculation (Example):




3. The number of pulses per mile is calculated (see illustration).

Divide Ratio Calculation (Example):




4. The divide ratio is calculated (see illustration).

5. In Table 1, 0.573529 is not present. The next largest number on the table is 0.578125. The correct code is therefore 0001110, so the pins at terminals 4, 3, and 2 must be removed.