Fail-Safe Chart

FAIL SAFE CHART

1. FAIL SAFE OPERATION

- If there is a problem with sensor signals or hydraulic brake booster systems, the skid control ECU prohibits power supply to the hydraulic brake booster and informs the ECM of VSC system failure.

The hydraulic brake booster turns off each solenoid and the ECM shuts off VSC control (traction control signal) from the skid control ECU accordingly, which turns out to be as if the ABS, TRAC and VSC systems were not installed.

The ABS control will be prohibited, but EBD control continues as much as possible. If EBD control is impossible, the BRAKE warning light comes on to warn the driver.

- If system components have any malfunction before starting control, immediately stop the operation. If system components have any malfunction during control, gradually stop the control so as not to trigger a sudden change in vehicle conditions. If it is impossible to control the systems, the warning light comes on to inform the driver of termination of the systems.

HINT: If the hydraulic brake booster encounters a malfunction, brake performance is gradually lost and ABS, BA, TRAC, A-TRAC, VSC, DAC and HAC system control is prohibited.




ABS & EBD & BA system:

HINT: A malfunction in either the ABS or BA system will result in an identical operation, with ABS, BA, TRAC, A- TRAC, VSC, DAC and HAC system control prohibited.




TRAC & A-TRAC & VSC & DAC & HAC system:

HINT: As for the TRAC, A-TRAC, VSC, DAC and HAC systems, different systems prohibit different controls according to a malfunctioning part.

2. SYSTEM TEMPERATURE PROTECTION OPERATION




If the TRAC, A-TRAC, DAC, or HAC system has been used constantly for a long time, the temperature of the hydraulic brake booster may excessively increase. If the temperature excessively increases, the skid control buzzer will sound intermittently. If the temperature increases more, the skid control buzzer sounds for 3 seconds and the indicator light either comes on or blinks.

HINT:
- If the SLIP indicator light goes off (as for the DAC system, the DAC indicator light also comes on), the systems automatically return to normal operating conditions.
- As this is not a malfunction, no DTC will be recorded.