FAIL-SAFE CHART
FAIL-SAFE FUNCTION
(a) When communication fails in any of the CAN bus lines (communication lines), a fail-safe function(s) will operate. The fail-safe function that is specified for each system operates to prevent those systems from malfunctioning.
(b) The following table shows the effects on each system when communication is impossible. (For further details, see the pages for each system.)
Function | Control Master | System Related | Fail-safe Operation | Driver Detectable | DTC Detection (ECU that stored DTC) |
---|---|---|---|---|---|
Air Conditioning Control
| Air conditioning amplifier assembly | ECM | Control is performed based on default coolant temperature of 80°C (176°F). | - | U0100 (Air conditioning amplifier assembly) |
Compressor Control
| Air conditioning amplifier assembly | ECM | Control is performed based on default engine speed of 0 rpm. | - | U0100 (Air conditioning amplifier assembly) |
Simple Load Control
| Air conditioning amplifier assembly | Power steering ECU assembly | Load control is not performed. | - | U0131 (Air conditioning amplifier assembly) |
Panel Dimming Control
| Air conditioning amplifier assembly | Main body ECU (multiplex network body ECU) | Dimming mode and non-dimming mode cannot be switched. | - | U0142 (Air conditioning amplifier assembly) |
Destination Identification Control
| Air conditioning amplifier assembly | Main body ECU (multiplex network body ECU) | Maintains the latest state. | - | U0142 (Air conditioning amplifier assembly) |
Insolation Correction Control
| Air conditioning amplifier assembly | Main body ECU (multiplex network body ECU) | While the engine switch on (IG), previous values are maintained. | - | U0142 (Air conditioning amplifier assembly) |
Ambient Temperature Correction Control
| Air conditioning amplifier assembly | Combination meter assembly | Control is performed based on default vehicle speed of 0 km/h (0 mph). |
| U0155 (Air conditioning amplifier assembly) |
Air Conditioning Eco Mode Control
| Air conditioning amplifier assembly | ECM | Maintains the latest state (Maintained in normal condition after reset). | - | U0101 (Air conditioning amplifier assembly) |
Door Lock
| Main body ECU (multiplex network body ECU) |
|
| - | U0100 U0101 U0151 U0155 (Main body ECU (multiplex network body ECU)) |
Display Automatic Dimming
| Main body ECU (multiplex network body ECU) | Combination meter assembly | Automatic dimming control for displays does not operate when taillights are turned on. | - | U0155 (Main body ECU (multiplex network body ECU)) |
Back Door Opener
| Main body ECU (multiplex network body ECU) |
|
| - | U0155 U0230 (Main body ECU (multiplex network body ECU)) |
Illumination Control | Main body ECU (multiplex network body ECU) |
|
| - | U0101 U0327 (Main body ECU (multiplex network body ECU)) |
Seat and Mirror Control
| Main body ECU (multiplex network body ECU) |
|
| - | U0155 U0199 U0200 U0208 U0327 U1115 (Main body ECU (multiplex network body ECU)) |
Smart Beam
| Main body ECU (multiplex network body ECU) |
| Smart beam system does not operate. | Displays messages on the multi-information display. | U0182 U023A (Main body ECU (multiplex network body ECU)) |
Engine System Indicator Display
| ECM | Combination meter assembly |
| - | - |
Electric Load Control
| ECM |
| Idle up according to electric load is not performed. | Not possible. (Idle speed changes.) | - |
Air Conditioning Cooperative Operation
| ECM | Air conditioning amplifier assembly | Air conditioning system does not use cooperative controls. (Idle up is not performed.) | Air conditioning system does not operate. | - |
PTC Heater
| ECM | Air conditioning amplifier assembly | PTC heater does not operate. |
| - |
Charge Control
| ECM |
| Idle up according to charging request is not performed. | Taillights flicker and blower airflow changes. | - |
Eco Control
| ECM | Air conditioning amplifier assembly | Eco mode does not operate. | - | - |
ECT System Indicator Display
| ECM | Combination meter assembly | Indicator light does not illuminate. | - | - |
Coast Downshift Timing Change According to Air Conditioning Load
| ECM | Air conditioning amplifier assembly | Coast downshift does not occur. | Coast downshift shock reduction performance deteriorates. | - |
Cruise Control
| ECM |
| Cruise control does not operate. | Displays messages on the multi-information display. | U012287 (ECM) |
Power Steering Control
| Power steering ECU assembly |
| Assist force restricted. | - | U0100 U0129 (Power steering ECU assembly) |
VDIMα System
|
| Skid control ECU (brake actuator assembly) | VDIMα control is stopped. | - | - |
LKA System
|
|
| LKA control is stopped. | - | U0129 (Power steering ECU assembly) |
Entry Function
|
|
| Entry unlock is performed again. |
| U0100 U0142 U0155 (Certification ECU (smart key ECU assembly)) |
Entry Function/Wireless Control | Main body ECU (multiplex network body ECU) |
| Entry lock/unlock control is not possible. | - | U0142 (Certification ECU (smart key ECU assembly)) |
Engine Switch Backlighting Control
| Certification ECU (smart key ECU assembly) |
| Engine switch backlighting does not illuminate according to interior lights operation. | - | U0142 (Certification ECU (smart key ECU assembly)) |
Security Indicator Display Function
| Certification ECU (smart key ECU assembly) | Main body ECU (multiplex network body ECU) | Security indicator cannot display security status correctly (security indicator blinks or illuminates when in armed state or alarm sounding state). | - | U0142 (Certification ECU (smart key ECU assembly)) |
Vehicle Speed Display | Combination meter assembly | Skid control ECU (brake actuator assembly) | Speedometer is controlled based on a default vehicle speed of 0 km/h (0 mph). |
| U0129 (Combination meter assembly) |
Tachometer Display | Combination meter assembly | ECM | Needle of tachometer remains at 0 rpm. | MIL illuminates. | U0100 (Combination meter assembly) |
Meter Display
| Combination meter assembly |
| Lights do not illuminate or lights remain illuminated. | Abnormal light operation | U0131 U0151 U0182 U1104 (Combination meter assembly) |
ABS control | Skid control ECU (brake actuator assembly) |
| When control is being performed:
When control is not being performed:
|
| U007488 U010087 U010187 U012587 U012687 U015187 (Skid control ECU (brake actuator assembly)) |
VSC/TRAC/VDIM | Skid control ECU (brake actuator assembly) |
| Control cannot be performed. |
| U007488 U010087 U010187 U012587 U012687 U015187 (Skid control ECU (brake actuator assembly)) |
Hill-start Assist Control
| Skid control ECU (brake actuator assembly) |
| Control cannot be performed. |
| U007488 U010087 U010187 U012587 U012687 U015187 (Skid control ECU (brake actuator assembly)) |
Brake Hold Control
| Skid control ECU (brake actuator assembly) |
| Control cannot be performed. |
| U007488 U010087 U010187 U012587 U012687 U015187 (Skid control ECU (brake actuator assembly)) |
Headlight Leveling Control (Headlight Control)
| Headlight ECU sub-assembly LH |
| Headlight Leveling Control is stopped. | - | U0100 (for Multiple Beam Headlight or Single Beam Headlight w/ Automatic Headlight Beam Level Control System) U0129 U0142 (Headlight ECU sub-assembly LH) |
Cornering Light
| Headlight ECU sub-assembly LH |
| Cornering light Control is stopped. | - | U0101 U0126 U0129 U0142 U0155 (Headlight ECU sub-assembly LH) |
Low Beam, High Beam
| Main body ECU (multiplex network body ECU) | Headlight ECU sub-assembly LH | Forces the low beams to illuminate. | - | U0073 U0142 U1000 (Headlight ECU sub-assembly LH) |
AVS Control
| Absorber control ECU |
|
| - | U0100 U0122 U0124 U0126 (Absorber control ECU) |
Air Conditioning Control
| Radio receiver assembly | Air conditioning amplifier assembly |
| - | U0164 (Radio receiver assembly) |
Intuitive Parking Assist System Setting/Notification
| Radio receiver assembly |
| Transitions to the previous screen. | - | U1110 (Radio receiver assembly) |
Fuel Consumption Display
| Radio receiver assembly |
|
| - | U0100 U0129 U0155 (Radio receiver assembly) |
Destination Identification
| Radio receiver assembly | Main body ECU (multiplex network body ECU) | Determines the destination according to the last received value and operates accordingly (if there is no last received value, the system operates using the default value). | Time zone and language selection screen are different from actual destination. | U0140 (Radio receiver assembly) |
Tire Pressure Monitoring System
| Main body ECU (multiplex network body ECU) |
|
| - | U0073 (Radio receiver assembly) |
Power Tilt and Power Telescopic Steering Column Control
| Multiplex tilt and telescopic ECU |
|
| - | U0142 U0208 (Multiplex tilt and telescopic ECU) |
Seat Position Memory System
| Position control ECU and switch assembly LH |
| Controls the seat position based on operation conditions. | - | - |
Mirror Surface Adjustment |
| Main body ECU (multiplex network body ECU) | Mirror surface position cannot be memorized or recalled. | - | - |
Mirror Heaters |
|
| Mirror heaters do not operate. | - | U0142 (Outer mirror control ECU assembly) |
Mirror Retract/Return Operation
|
| Main body ECU (multiplex network body ECU) | Mirrors cannot be retracted or returned. | - | U0142 (Outer mirror control ECU assembly) |
Reverse-shift Linked Door Mirror Operation |
| Main body ECU (multiplex network body ECU) | Reverse-shift linked door mirror function does not operate. | - | - |
Mirror Surface Position Memory and Recall |
| Main body ECU (multiplex network body ECU) | Mirror surface position cannot be memorized or recalled. | - | - |
Illumination Control
|
| Main body ECU (multiplex network body ECU) | Mirror foot illumination is turned off. | - | U0142 (Outer mirror control ECU assembly) |
Seat Memory Switch Signal Forwarding
| Main body ECU (multiplex network body ECU) |
| Seat position memory settings cannot be memorized or recalled. | - | - |
Dynamic Radar Cruise Control System
| ECM |
| Control stops. | Displays messages on the multi-information display. | U010087 U010487 U012287 (ECM) |
Vehicle Speed Judgment
| Clearance warning ECU assembly | Skid control ECU (brake actuator assembly) | Clearance sonar detection will be operated based on a vehicle speed of 20 km/h or more. | - | - |
Mute Switch Judgment
| Clearance warning ECU assembly | Combination meter assembly | Control operates with the latest setting. | - | U0155 (Clearance warning ECU assembly) |
Intuitive Parking Assist System Control | Clearance warning ECU assembly | Clearance warning ECU assembly | Intuitive parking assist system does not operate. | Clearance sonar indicator does not operate. | U0073 (Clearance warning ECU assembly) |
Shift Position Judgment
| Clearance warning ECU assembly | ECM | Control operates with the default shift position P. | - | U0100 (Clearance warning ECU assembly) |
Intelligent Clearance Sonar System
| Clearance warning ECU assembly |
| Intelligent clearance sonar control is stopped. |
| U0073 U0100 U0124 U0126 U0129 U0151 U1000 (Clearance warning ECU assembly) |
Rear Cross Traffic Auto Brake Function
| Clearance warning ECU assembly |
| Rear cross traffic auto brake control is stopped. |
| U0232 U0233 (Clearance warning ECU assembly) |
Automatic High Beam System
| Forward recognition camera |
| Performs control based on the signals received before the malfunction occurred. |
| U010087 U012587 U012987 U014087 U023587 (Forward recognition camera) |
Front Camera System
| Forward recognition camera |
| Performs control based on the signals received before the malfunction occurred. | Displays messages on the multi-information display. | U010087 U012587 U012687 U012987 U014087 (Forward recognition camera) |
Lane Tracing Assist system
| Forward recognition camera |
| Control stops. | Displays messages on the multi-information display. | U010087 U012587 U012687 U012987 U013187 U015587 U023587 U030051 U030057 (Forward recognition camera) |
Road Sign Assist Function
| Forward recognition camera |
| Road sign assist function is canceled. | Displays messages on the multi-information display. | U010087 U012587 U012987 U014087 U015587 (Forward recognition camera) |
Pre-collision System
| Forward recognition camera |
| Pre-collision alarm function, pre-collision brake assist function and pre-collision brake function are canceled. |
| U010087 U012587 U012687 U012987 U023587 U023A87 U030051 U030057 U041881 (Forward recognition camera) |
Dynamic Radar Cruise Control System
| Forward recognition camera |
| Control stops. | Displays messages on the multi-information display. | U010087 U012587 U012687 U012987 U015587 U023587 U110687 (Forward recognition camera) |
Blind Spot Monitor Control
| Blind spot monitor sensor LH |
| - | Displays messages on the multi-information display. | U0100 U0125 U0126 U0129 U0142 (Blind spot monitor sensor LH) |
Parking Assist Monitor System
| Rear television camera assembly |
| Parking assist monitor function is prohibited. |
| U0100 U0126 U0140 U0163 U1110 (Rear television camera assembly) |
Auto Location
| Tire pressure warning ECU and receiver | Skid control ECU (brake actuator assembly) | Auto Location function is prohibited. | - | U0129 (Tire pressure warning ECU and receiver) |
Panoramic View Monitor
| Parking assist ECU |
| Panoramic view monitor system does not operate. | - | U0073 U0100 U0126 U0129 U0140 U0163 U0233 U0265 U1110 (Parking assist ECU) |
ATC-4WD System
| 4WD ECU assembly |
| Depending on the malfunctioning communication line, any of the following controls are performed.
| Displays messages on the multi- information display. | U0073 U0100 U0126 U0129 (4WD ECU assembly) |
Headup Display (Tachometer) | Combination meter mirror ECU (headup display) | ECM | The tachometer in the headup display shows that the engine speed is 0 rpm. | - | U0100 (Combination meter mirror ECU (headup display)) |
Headup Display (LKA/LDA System) | Combination meter mirror ECU (headup display) | Forward recognition camera | Lane markers are not displayed. | - | U023A (Combination meter mirror ECU (headup display)) |
Driver seat switch operation function
| Multiplex network door ECU |
|
| - | U0101 U0142 U0155 (Multiplex network door ECU) |
Wireless switch operation
| Multiplex network door ECU |
|
| - | U0142 U0327 (Multiplex network door ECU) |
Back door handle operation
| Multiplex network door ECU | Main body ECU (multiplex network body ECU) | Power back door open does not operate. | - | U0142 (Multiplex network door ECU) |
Touchless power back door operation
| Multiplex network door ECU | Main body ECU (multiplex network body ECU) | Power back door automatic open/close does not operate. | - | U0142 (Multiplex network door ECU) |
Pre-collision System
| Millimeter wave radar sensor assembly | Forward recognition camera | Sensing (measured distance) is disabled. | Displays messages on the multi-information display. | U010487 (Millimeter wave radar sensor assembly) |
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