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Fail-Safe Chart [11/2023 - ]

If any of the following DTCs are stored, the engine stop and start ECU enters fail-safe mode to preserve vehicle operability.

DTC Component Fail-safe Operation Fail-safe Deactivation Condition
P0555-00
P0555-2A
  • Vacuum sensor assembly
  • Brake booster assembly
  • Vacuum hose (brake booster hose)
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 One of the following conditions is met:
  • Vacuum changes while the brake pedal is depressed
  • Vacuum changes a specified number of times while the vehicle is being driven faster than a certain vehicle speed
P0555-11
P0555-15		 Vacuum sensor assembly circuit
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Sensor output is within standard range
P0604-44 Engine stop and start ECU Stop and start control is prohibited Pass condition detected and DTC is cleared
P0606-29 Engine stop and start ECU
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Pass condition detected and ignition switch turned to ON
P060B-1C
P060B-49
P060B-71		 Analog to digital converter (Engine stop and start ECU) Stop and start control is prohibited Pass condition detected and ignition switch turned to ON
P0615-11 ST relay circuit Stop and start control is prohibited Pass condition detected and DTCs are cleared
P0615-19 Starter circuit
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Communication with ECM returns to normal and one of the following conditions is met:
  • The STA signal detected by the ECM and STA signals detected by the engine stop and start ECU are on for 0.3 seconds
  • The STA signal detected by the ECM and STA signals detected by the engine stop and start ECU are off for 5 seconds
P1644-00
  • Starter drive circuit
  • ST relay
  • Engine stop and start ECU
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Voltage of engine stop and start ECU internal drive circuit for starter is correct when engine is idling and restarted
P2530-14 IG signal circuit
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 All of the following conditions are met for 10 seconds or more:
  • Ignition switch ON
  • Normal communication with ECM
P323A-00
P323A-16
P323B-14
P323B-29
P323B-38		 Backup boost converter circuit
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Pass condition detected and DTCs are cleared
U0100-87 CAN communication (ECM)
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Communication with engine stop and start ECU continues for 2 seconds or more
U0101-87 CAN communication (TCM)
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Communication with engine stop and start ECU continues for 1 second
U0129-87 CAN communication (skid control ECU (brake actuator assembly))
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Communication with engine stop and start ECU continues for 4.4 seconds or more
U0140-87 CAN communication (main body ECU (multiplex network body ECU)) - Communication with engine stop and start ECU continues for 7.2 seconds or more
U0151-87 CAN communication (airbag sensor assembly) - Communication with engine stop and start ECU continues for 21.2 seconds or more
U0155-87 CAN communication (combination meter assembly)
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Communication with engine stop and start ECU continues for 21.2 seconds or more
U0164-87 CAN communication (air conditioning amplifier assembly) - Communication with engine stop and start ECU continues for 21.2 seconds or more
U1170-87 Local CAN communication (skid control ECU (brake actuator assembly))
  • Stop and start control is prohibited
  • Engine is automatically restarted if a DTC is stored while the engine is stopped by stop and start control
 Communication with engine stop and start ECU continues for 21.2 seconds or more
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