The Hill start Assist Control (HAC) function helps the vehicle not sleep when start up on a steep hill. The HAC function is operated when the vehicle is on the decline and brake lamp is illuminated when the HAC is operating.
The HECU monitors the brake lamp relay (brake lamp relay) for normal operation. If there is an open or a short in the relay circuit, this DTC is set.
Item | Detecting Condition | Possible cause |
DTC Strategy |
•
Voltage Monitoring | 1. Open or short in the brake lamp relay(brake lamp relay) circuit 2. Faulty brake lamp relay(brake lamp relay) |
Monitoring Period |
•
During HAC activation and brake light switch signal off, the fault is detected with mismatch between the corresponding lamp actuation signal and electrical feedback signa for more than 600ms. | |
Fail-Safe |
•
Inhibit the HAC control and allow the ABS/EBD/ESP control.
•
The ESP warning lamp is activated. |
