Terminals Of ECM
WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK ECM
- Measure the voltage of the connectors.ECU CONNECTOR TERMINAL SPECIFIED CONDITION
Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition STP (E5-4) - E1 (E3-7) G-R - BR Stop light switch input signal Brake pedal released (Stop light switch OFF) Below 1 V STP (E5-4) - E1 (E3-7) G-R - BR Stop light switch input signal Brake pedal depressed (Stop light switch ON) 10 to 14 V CCS (E5-31) - E1 (E3-7) R-BR Cruise control main switch output signal Ignition switch ON 10 to 14 V CCS (E5-31) - E1 (E3-7) R - BR Cruise control main switch output signal Ignition switch ON, CANCEL switch ON 6.6 to 10.1 V CCS (E5-31) - E1 (E3-7) R - BR Cruise control main switch output signal Ignition switch ON, -/SET switch ON 4.5 to 7.1 V CCS (E5-31) - E1 (E3-7) R - BR Cruise control main switch output signal Ignition switch ON, +/RES switch ON 2.3 to 4 V CCS (E5-31) - E1 (E3-7) R - BR Cruise control main switch output signal Ignition switch ON, Main switch ON Below 1 V ST1- (E6-8) - E1 (E3-7) Y-G - BR Cruise cancel input signal Ignition switch ON, Brake pedal depressed (Stop light switch ON) Below 1 V ST1- (E6-8) - E1 (E3-7) Y-G - BR Cruise cancel input signal Ignition switch ON, Brake pedal released (Stop light switch OFF) 10 to 14 V E1 (E3-7) - Body ground BR - Body ground Ground Always Below 1 V SPD (E6-22) - E1 (E3-7) W-R - BR Vehicle speed is actual speed Vehicle is driving Pulse generation (see b waveform 1) If the result is not as specified, the ECM may have a malfunction.
- Inspect using an oscilloscope.
Waveform 1 (Reference)
WAVEFORM REFERENCE CHARTItem Content Symbols (Terminal No.) SPD (E6-22) - E1 (E4-7) Tool Setting 2 V/DIV., 20 msec./DIV. Vehicle Speed 20 km/h (12 mph) HINT:
The wavelength becomes shorter as vehicle speed increases.
- Measure the voltage of the connectors.