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For 1990-2009 cars only

Ultrasonic Sensor Function Inoperative Genuine Accessory

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

After the alarm system has been armed, causing movement inside the cabin of the vehicle, will cause the alarm siren to be activated. The alarm movement detection feature consists of two ultrasonic sensors and an ultrasonic module. The one sensor transmits an ultrasonic signal and the other sensor receives the ultrasonic signal. When there is a distortion of the ultrasonic sound waves, the ultrasonic module will interpret this as movement. The ultrasonic module will relay this information to the alarm module which in turn will activate the siren. Inoperative ultrasonic function can be caused by the following:

    • Ultrasonic sensor sensitivity set too low.
    • Ultrasonic sensor wiring damaged.
    • The ultrasonic sensors incorrectly connected to the ultrasonic module.
    • Short circuit to ground or incorrect function of the disable switch.
    • Incorrect or poor wiring connections between the alarm module and the body control module.
    • Tilt sensor incorrectly connected to the alarm module

Reference Information

Schematic Reference

Theft Deterrent System Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Testing

Ultrasonic Sensor Sensitivity Set Too Low

  1. Ignition OFF, locate the ultrasonic module sensitivity adjustment screw.
  2. Using a suitable flat blade screwdriver, turn the ultrasonic sensitivity adjustment screw until the marker indicates a higher value. A setting of between 2 and 3 is recommended (do not set to a value of 1).
  3. Function test the alarm ultrasonics before reassembling the vehicle. Adjust the ultrasonic sensitivity if further adjustment is necessary.

Ultrasonic Sensor Wiring Damaged

  1. Locate the ultrasonic sensor wiring.
  2. Inspect the ultrasonic sensors harness routing, ensuring that the cables are not pinched or damaged.
  3. Inspect the ultrasonic sensor connectors at the ultrasonic module for damage.

Ultrasonic Sensors Incorrectly Connected to the Ultrasonic Module

  1. Locate the 2-terminal connector socket on the ultrasonics module marked 'RED'. Ensure that one of the wires that is on the plug connector that connects to the socket marked 'RED' is in fact RED.
  2. Locate the 2-terminal connector socket on the ultrasonics module marked 'BLACK'. Ensure that one of the wires that is on the plug connector that connects to the socket marked 'BLACK' is either BLACK or WHITE.
  3. Ensure that the 4-terminal connector is firmly connected to the centre location on the ultrasonics module.

Short Circuit to Ground or Incorrect Function of the Disable Switch

  1. Ignition OFF, alarm module connector and disable switch disconnected.
  2. Test for infinite resistance between the alarm module harness connector terminal 11 and ground.
  3. If not the specified value, replace the alarm module harness.
  4. Connect the disable switch.
  5. While pressing the disable button, test for less than 1.0 ohm resistance between the alarm module harness connector terminal 11 and ground.
  6. If not the specified value, replace the disable switch.
  7. Release the disable button and test for infinite resistance between the alarm module harness connector terminal 11 and ground.
  8. If not the specified value, replace the disable switch.

Incorrect or Poor Wiring Connections Between the Alarm Module and the Body Control Module

  1. Ignition OFF, alarm module connector disconnected.
  2. Locate the body control module (BCM) connectors  X5 and X6
  3. Test for less than 1 ohm resistance between the BCM harness connector terminal X6-16 and the alarm module harness connector terminal 8.
  4. If not the specified value, replace the harness.
  5. Test for less than 1 ohm resistance between the BCM harness connector terminal X5-18 and the alarm module harness connector terminal 2.
  6. If not the specified value, replace the harness.

Tilt Sensor Incorrectly Connected to the Alarm Module

If the tilt sensor is incorrectly connected to the alarm module the alarm module may not initialize. Refer to the diagnostic procedure for the tilt sensor wiring.

Repair Instructions

For component removal and installation refer to the accessory fitting instructions.