Component Tests and General Diagnostics

Inspection of BCM and Its Circuits

Voltage and Signal Check
Check voltage and/or pulse signal of BCM (1) using voltmeter (2) and oscilloscope (3).

NOTE:
- Check that battery voltage is 11 V or more.
- For "Ignition mode" described in the following table, it means power supply mode in keyless push start system.
For more details of ignition mode, refer to Description of Keyless Engine Start Function.
- The voltage of terminal with asterisk (*) cannot be measured by voltmeter because it is pulse signal. Check it with oscilloscope if necessary.


























Reference Waveform

Oscilloscope display
Shown below is typical waveform display provided by oscilloscope.

NOTE:
- Display includes the following types of data:







- Waveforms may vary with measurement conditions and vehicle specifications.

CAN communication signal

CAN communication signal (high) (1):







CAN communication signal (low) (2):







Measurement condition
- Ignition mode: ON







Shift up switch signal, shift down switch signal, brake fluid level switch signal, lighting switch signal, trunk lid opener switch signal, power door lock switch signal and parking brake switch signal

Shift up switch signal:







Measurement condition
- Ignition mode: ON
- Shift up switch: OFF

Shift down switch signal:







Measurement condition
- Ignition mode: ON
- Shift down switch: OFF

Brake fluid level switch signal:







Measurement condition
- Ignition mode: ON
- Brake fluid level switch: OFF (brake warning light: OFF)

Lighting switch (CLEARANCE) signal:







Measurement condition
- Ignition mode: ON
- Lighting switch: Other than CLEARANCE position

Lighting switch (AUTO) signal:







Measurement condition
- Ignition mode: ON
- Lighting switch: Other than AUTO position

Trunk lid opener switch signal:






Measurement condition
- Ignition mode: ON
- Trunk lid opener switch: Release

Power door lock switch (Unlock) signal:







Measurement condition
- Power door lock switch (Unlock): OFF

Power door lock switch (Lock) signal:







Measurement condition
- Power door lock switch (Lock): OFF

Parking brake switch signal:







Measurement condition
- Ignition mode: ON
- Parking brake switch: OFF







DRL control signal







Measurement condition
- DRL: ON







Oil pressure switch signal







Measurement condition
- Engine: Running







Wiper switch (AUTO / INT) signal and turn signal switch signal

Wiper switch (AUTO / INT) signal:







Measurement condition
- Ignition mode: ON
- Wiper switch: Other than AUTO / INT position

Turn signal switch (L) signal:







Measurement condition
- Ignition mode: ON
- Turn signal switch (L): OFF

Turn signal switch (R) signal:







Measurement condition
- Ignition mode: ON
- Turn signal switch (R): OFF







Hazard warning switch signal and trunk lid opener cancel switch signal

Hazard warning switch signal:







Measurement condition
- Hazard warning switch: OFF

Trunk lid opener cancel switch signal:







Measurement condition
- Trunk lid opener cancel switch: OFF







Vehicle speed signal







Measurement condition
- Vehicle speed: 40 km/h (25 mph)







Front dome light control signal

Front dome light control (DOOR) signal:







Measurement condition
- Front dome light switch: "DOOR" position
- Any one of the door: Open

Front dome light control (ON) signal:







Measurement condition
- Front dome light switch: "ON" position







Vanity mirror light and rear dome light (ON) signal







Measurement condition
- Vanity mirror light or rear dome light: ON