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

Electronic Throttle Actuator: Testing and Inspection

Inspection Using An Oscilloscope (Reference)

NOTE: The duty ratio for the wave pattern can vary with the control conditions. Therefore determine comprehensively where the malfunction occurs among the input systems, output systems, and the PCM,

Throttle control (+)




- Terminal connected: 1B (+) - Negative battery terminal
- Oscilloscope setting; 5 V/DIV (Y): 0.4 ms/DIV (X), DC range
- Measurement condition: IG SW ON

Throttle control (-)




- Terminal connected: 1C (+) - Negative battery terminal
- Oscilloscope setting: 5 V/DIV (Y): 1 ms/DIV (X), DC range
- Measurement condition: As soon as the accelerator pedal is fully released from the fully depressed position while the ignition switch is at ON (engine off).