Rear Park Assist Sensors Faulty or Inoperative Genuine Accessory
Diagnostic Fault Information
Perform the
Diagnostic System Check - Vehicle prior
to using this diagnostic procedure.
Circuit/System Description
The parking sensors, situated in the rear bumper operate both as transmitters
and receivers of ultrasonic signals. When the system is active and these ultrasonic
sound waves are distorted the rear park assist (RPA) module interprets this as an
approaching object and will alert the driver by sounding a sequence of pulses or continuous
tone from the warning buzzer.
Reference Information
Schematic Reference
Object Detection Schematics.
Connector End View Reference
Component Connector End Views
Electrical Information Reference
Circuit/System Testing
Important: Prior to performing circuit/system testing,
ensure that the RPA module is receiving a satisfactory power/ground supply when reverse
is selected. Refer to: Rear park assist inoperative.
Important: If one or more RPA sensors are suspected
of being faulty perform the RPA sensor component test prior to performing circuit/system
testing to identify the faulty sensor(s).
- Ignition OFF, disconnect the parking sensor harness connectors.
- Ignition ON, engine OFF, select reverse and test for (4.8 -- 5.2)
volts between the 5-volt reference circuit terminal 2 and ground. Repeat
for all sensors.
⇒ | If any value is less than the specified range, test the 5-volt reference
circuit for a short to ground or an open/high resistance. If greater than the specified
range, test the 5-volt reference circuit for a short to voltage. |
- Ignition OFF, disconnect the parking sensor harness connectors X2, X3,
X4, X5 at the RPA module.
Test for less than 1.0 Ohm resistance
between each low reference circuit listed below.
• | Right rear parking sensor terminal 1 and RPA connector X5 1. |
• | Centre right rear parking sensor terminal 1 and RPA connector X4 1. |
• | Centre left rear parking sensor terminal 1 and RPA connector X3 1. |
• | Left rear parking sensor terminal 1 and RPA connector X2 1. |
⇒ | If greater than the specified value, test the harness for open/high resistance. |
- Test for infinite resistance to ground. Repeat for all circuits listed
below:
• | Right rear parking sensor harness terminal 1 |
• | Centre right rear parking sensor harness terminal 1 |
• | Centre left rear parking sensor harness terminal 1 |
• | Left rear parking sensor harness terminal 1 |
⇒ | If not the specified value, repair/replace the parking sensor harness. If the
circuits test normal, replace the RPA module. |
Component Testing
Important: When removing connectors inspect for damage
or corrosion. Damage or corrosion in the following areas will require repair or replacement
of the affected component/connector.
• | RPA module harness connectors. |
• | RPA sensor harness connectors. |
Complex objects may not be detected if the transmitted sound waves are
reflected away from the objects rather than returning to the receiving parking sensor.
- Ensure parking sensors are clean of road dirt.
- Ensure parking sensors are not damaged.
- Verify parking sensors are correctly installed.
⇒ | Refer to installation instructions. |
- Ignition OFF, disconnect harness connectors X3, X4, X5 at the RPA module.
- Ignition ON, engine OFF, select reverse.
- Place an RPA detectable object in front of the left rear parking sensor,
the RPA warning buzzer should sound continuously. Move the object in small increments
away from the left rear parking sensor. The warning buzzer should reduce its continuous
sound to a decreasing pulsating sound as the object is moved further away from the
left rear parking sensor.
⇒ | If the RPA system is not triggered by the left rear parking sensor, turn the
ignition OFF and disconnect X2 at the RPA module and connect it to the X5 socket at
the RPA module. Ignition ON, engine OFF, select reverse and repeat test step 6.
If the RPA system does not respond disconnect the left rear parking sensor and substitute
a known good parking sensor. If the RPA system still do not respond, replace the RPA
module. |
Important: Ensure that the ignition is turned OFF before
the parking sensors are disconnected and ON when the test is performed.
- Substitute the left rear parking sensor with the rest of the parking sensors
one after the other and repeat test step 6 for each parking sensor. Replace
any of the parking sensors if:
• | A parking sensor does not trigger the RPA system. |
• | A parking sensor causes the system to sound continuously even after the
object has been removed. |
• | A parking sensor does not cause the RPA system to change to a pulsating
sound. |
• | A parking sensor appears to be too sensitive. |
Repair Instructions
For component removal and installation refer to the accessory fitting instructions.
Perform the
Diagnostic Repair Verification after
completing the diagnostic procedure.