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Tahoe / Yukon Service Manual

DTC B1A30 (UD5)

Diagnostic Instructions Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Review Strategy Based Diagnosis for an overview of the diagnostic approach. Diagnostic Procedure Instructions provides an overview of each diagnostic category. DTC Descriptors DTC B1A30 Object Sensor Voltage Reference For symptom byte information, refer to Symptom Byte List. Diagnostic Fault Information

Circuit Circuit Function Short to Ground Open/High Resistance Short to Voltage Signal Performan
2374 Voltage Reference B1A30 11 B132B 16, B132C 16, B132D 16, B132E 16, B13B0 16, B13B1 16 B1A30 12 —
6581 Voltage Reference B1A30 11 B13AE 16, B13AF 16, B13BB 16, B13BC 16, B13BD 16, B13BE 16 B1A30 12 —

Circuit/System Description The B306 Parking Assist Alarm Sensors are 3-wire ultrasonic sensors that are used to determine the distance between the vehicle and an object. The K182 Parking Assist Control Module supplies a voltage reference to the B306 Parking Assist Alarm Sensors via voltage reference circuits 2374 and 6581 and provides ground via low reference circuits 2379 and 5214. The K182 Parking Assist Control Module triggers the B306 Parking Assist Alarm Sensors in a sequential loop. After each B306 Parking Assist Alarm Sensor transmits, the K182 Parking Assist Control Module uses the sensor echo received through the signal circuits to calculate the distance and position of an object. Conditions for Running the DTC Ignition ON Conditions for Setting the DTC B1A30 11 The K182 Parking Assist Control Module has determined the voltage reference circuit 2374 or 6581 is shorted to ground B1A30 12 The K182 Parking Assist Control Module has determined the voltage reference circuit 2374 or 6581 is shorted to voltage B1A30 19 The K182 Parking Assist Control Module has identified high current on the voltage reference circuit 2374 or 6581 Action Taken When the DTC Sets Parking assist is disabled. The driver information center may display a system service message. Conditions for Clearing the DTC The condition for setting the DTC is no longer present. Reference Information Schematic Reference Parking Assistance Systems Schematics Connector End View Reference Master Electrical Component List Description and Operation Parking Assist Description and Operation Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Scan Tool Reference Control Module References for scan tool information Circuit/System Testing

  1. Ignition OFF, disconnect the X2 and X3 connectors at the K182 Parking Assist Control Module.
  2. Test for infinite resistance between the following voltage reference circuit terminals and ground: Termina 4 X2 Termina 7 X3 ⇒ If less than infinite resistance Repair the short to ground on circuit 2374 or 6581. ⇓ If infinite resistance
  3. Ignition ON.
  4. Test for less than 1 V between the following voltage reference circuit terminals and ground: Termina 4 X2 Termina 7 X3 ⇒ If 1 V or greater Repair the short to voltage on circuit 2374 or 6581. ⇓ If less than 1 V
  5. Ignition OFF, connect the X2 and X3 connectors at the K182 Parking Assist Control Module.
  6. Disconnect the connector at each B306 Parking Assist Alarm Sensor, ignition ON.
  7. Verify DTC B1A30 is not set as current. ⇒ If DTC B1A30 is set as current Replace the K182 Parking Assist Control Module. ⇓ If DTC B1A30 is not set as current
  8. Connect each B306 Parking Assist Alarm Sensor, one at a time. Verify DTC B1A30 is not set as current after connecting each B306 Parking Assist Alarm Sensor. ⇒ If DTC B1A30 is set as current Replace the B306 Parking Assist Alarm Sensor that was connected immediately before DTC  B1A30 set as current. ⇓ If DTC B1A30 is not set as current
  9. A fault is currently not present and may be an intermittent condition. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Parking Assistance Systems Component Replacement Reference Control Module References for control module replacement, programming, and setup.