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

Function Diagnosis

[FUNCTION DIAGNOSIS]

The table below shows the service data and their normal condition, which are displayed during the "Function Diag." The column "Normal condition" shows values that are shown when each operation is made.


















NOTE: When checking the input signals (off, tail, low-beam or high-beam), turn the ignition switch to the "ON" position in order to disable the headlight automatic shutoff function. However, since the headlight operation does not depend on the ignition switch positions, the scan tool MB991958 (M.U.T.-III Sub Assembly) does not display the title "IGNITION SWITCH".

For checking item "HEADLIGHT HI", the scan tool MB991958 (M.U.T.-III Sub Assembly) displays "OFF" on the item No.2 "DIMMER SW" when the headlights are at high-beam. Therefore, the scan tool MB991958 (M.U.T.-III Sub Assembly) should display "ON" momentarily when the dimmer switch is operated.












NOTE: The headlight automatic shutoff function operates approximately one second after the lighting monitor tone alarm starts sounding, and then the tone alarm ceases sounding.