TOYOTA PARKING ASSIST-SENSOR SYSTEM PROBLEM SYMPTOMS TABLE

Tech Tips

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

General
Symptom	Suspected Area	See page
System does not operate at all (Initial check function also does not operate)	Proceed to "Clearance sonar main switch circuit"	Click here
	Proceed to "Parking brake switch circuit"	Click here
	Replace clearance warning ECU	Click here
System operates even when vehicle speed is 10 km/h (6.2 mph) or more	Proceed to "Speed Signal Circuit"	Click here
	Replace clearance warning ECU	Click here

Sonar Function
Symptom	Suspected Area	See page
Clearance warning indicator indicates front corner clearance sonar sensor is frozen	Clean sensor surface	Click here
	Proceed to "Front Corner Clearance Sonar Sensor LH Circuit"	Click here
	Proceed to "Front Corner Clearance Sonar Sensor RH Circuit"	Click here
	Replace clearance warning ECU	Click here
Clearance warning indicator indicates front center clearance sonar sensor is frozen	Clean sensor surface	Click here
	Proceed to "Front Center Clearance Sonar Sensor LH Circuit"	Click here
	Proceed to "Front Center Clearance Sonar Sensor RH Circuit"	Click here
	Replace clearance warning ECU	Click here
Clearance warning indicator indicates rear corner clearance sonar sensor is frozen	Clean sensor surface	Click here
	Proceed to "Rear Clearance Sonar Sensor LH Circuit"	Click here
	Proceed to "Rear Clearance Sonar Sensor RH Circuit"	Click here
	Replace clearance warning ECU	Click here
Clearance warning indicator indicates rear center sonar sensor is frozen	Clean sensor surface	Click here
	Proceed to "Back Sonar Sensor LH Circuit"	Click here
	Proceed to "Back Sonar Sensor RH Circuit"	Click here
	Replace clearance warning ECU	Click here
Clearance warning indicator indicates open in front clearance sonar sensor circuit	Initial check function	Click here
	Proceed to "Front Corner Clearance Sonar Sensor LH Circuit"	Click here
	Proceed to "Front Corner Clearance Sonar Sensor RH Circuit"	Click here
	Proceed to "Front Center Clearance Sonar Sensor LH Circuit"	Click here
	Proceed to "Front Center Clearance Sonar Sensor RH Circuit"	Click here
	Replace clearance warning ECU	Click here
Clearance warning indicator indicates open in rear clearance sonar sensor circuit	Initial check function	Click here
	Proceed to "Rear Clearance Sonar Sensor LH Circuit"	Click here
	Proceed to "Back Sonar Sensor LH Circuit"	Click here
	Proceed to "Back Sonar Sensor RH Circuit"	Click here
	Proceed to "Rear Clearance Sonar Sensor RH Circuit"	Click here
	Replace clearance warning ECU	Click here
Clearance sonar sensors operate when shift lever is not in R, or do not operate even when shift lever is in R	Proceed to "Park/Neutral Position Switch Circuit"*1	Click here
	Proceed to "Back-up Light Switch Circuit"*2	Click here
	Replace clearance warning ECU	Click here

*1: except Manual Transaxle
*2: for Manual Transaxle

Buzzer Function
Symptom	Suspected Area	See page
System operates but clearance warning buzzer does not sound	Proceed to "Clearance Warning Buzzer Circuit"	Click here
System operates but clearance warning buzzer does not sound	Replace clearance warning ECU	Click here
Clearance warning buzzer volume is low	Adjust buzzer volume	Click here
Clearance warning buzzer volume is low	Replace clearance warning ECU	Click here

Switch Function
Symptom	Suspected Area	See page
System cannot be turned off	Proceed to "Clearance Sonar Main Switch Circuit"	Click here
System cannot be turned off	Replace clearance warning ECU	Click here
Switch indicator does not illuminate when back sonar or clearance sonar switch is on	Inspect back sonar or clearance sonar switch assembly	Click here
	Proceed to "Clearance Sonar Main Switch Circuit"	Click here

Indicator Function
Symptom	Suspected Area	See page
Indicator does not dim at night, or illuminates dimly during daytime	Proceed to "Taillight Relay Circuit"	Click here
	Replace clearance warning ECU	Click here
Detection operation is normal but clearance warning indicator does not illuminate	Proceed to "Indicator Circuit"	Click here
	Replace clearance warning ECU	Click here