Toyota Sienna Service Manual: Radar Sensor Malfunction

DTC P1570 Radar Sensor Malfunction

DESCRIPTION

The laser sensor emits laser beams towards an object in front and measures the distance and direction of the object by receiving the beam reflections. Based on the reflections, the sensor calculates the difference in speed between your own vehicle and an object in front. This data is transmitted to the distance control ECU.

HINT: The laser sensor monitors the laser emission and reception by itself. This DTC is detected when it cannot monitor. When rain drops or snowflakes strike the laser sensor face, the distance between the vehicle in front and your own vehicle cannot be measured correctly. The dynamic laser cruise control system functions by detecting the reflector of the vehicle directly in front. In the following cases, the system may not be able to detect the vehicle in front and may not properly maintain the correct vehicle-to-vehicle distance:

•  The vehicle in front is a tall trailer.
•  The back of the vehicle in front is extremely dirty.
•  Emission from the vehicle in front or vehicles in other lanes is heavy.
•  The vehicle in front has no reflector.
•  The laser sensor is receiving a strong flash of light (sunlight, etc. )

INSPECTION PROCEDURE

NOTICE: When the laser sensor is replaced with a new one, adjustment of the laser sensor beam axis must be performed

1 ADJUST LASER SENSOR

Refer to adjustment.

HINT: It is necessary to make the ECM recognize specification information (whether the vehicle is equipped with the dynamic laser cruise control system or not). When this procedure has not been carried out, this DTC may be output.

1.  Clear the DTCs and then recheck for DTCs.

OK: DTC is not output.

SYSTEM IS OK