Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Input Displays
BCM input displays are operated as defined under SELECTING OF TESTS . When troubleshooting a malfunction, BCM input display can be used to determine if switched inputs can be properly interpreted.
When one of various input tests is selected, state of that device is displayed as HI or LO. The display also indicates if input changed state so that technician can activate or deactivate any listed device and return to display to see if it changed state. If a change of state occurred, an "X" will appear next to HI/LO indicator, otherwise a "O" will remain displayed.
The "X" will only appear once per selected input although HI/LO indication will continue to change as input changes. Some tests are momentary and "X" can be used as an indication of a change. The following is a list of BCM and LIGHTING inputs:
- BI03 Driver Door Jamb Switch
BI03 is LO when driver's door is open. - BI04 Passenger Door Jamb Switch
BI04 is LO when passengers door is open. - BI08 Low Refrigerant Pressure Switch
BI08 is LO when system is low on refrigerant. - BI09 Washer Fluid Level Switch
BI09 is LO when vehicle is low on washer fluid. - BI21 Brake Fluid Level Switch
BI21 will read HI with proper brake fluid level. - BI30 Time/Temp Switch
BI30 is LO when button is depressed. - BI55 Trunk Cylinder Switch
BI55 reads HI until key is rotated to unlock position in trunk lock cylinder. - BI60 Theft Alarm
BI60 indicates status of alarm output of theft module. LO indicates that theft deterrent has been setoff. HI is a normal reading. - BI61 Door Lock Switch
BI61 reads HI until key is rotated to unlock position in either door lock cylinder. - BI62 Soft Top Up Switch
BI62 will read LO with soft top up (if equipped). - BI63 Hard Top Connected
BI63 will read LO with hard top installed and connected (if equipped). - BI64 Oil Level Switch
BI64 will indicate LO with proper oil level. - BI90 Right Turn Signal
BI90 will indicate LO with right turn selected. - BI91 Left Turn Signal
BI91 will indicate LO with left turn selected. - BI92 Headlamp Switch
BI92 will read LO with headlamp switch ON - BI93 High Beam Switch
BI93 will indicate HI unless headlamp dimmer switch is pulled. - BI95 Brake Switch
BI95 will read HI with service brake applied.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.