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 logical successor to CHARM, I recommend you try it!

Link: lemon-manuals.la

Knock Retard

The scan tool displays 0-25.5 degrees. This indicates the amount of spark the PCM is removing from IC spark advance in response to the signal from the Knock Sensors (KS). The desired torque signal from the Electronic Brake And Traction Control Module (EBTCM) may cause knock retard to display a value greater than 0 degrees if the traction control is active.