Service Information

Volt

DTC B1405

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 B1405 02: Control Module Voltage Reference Output 2 Circuit Short to Ground

DTC B1405 03: Control Module Voltage Reference Output 2 Circuit Low Voltage

DTC B1405 07: Control Module Voltage Reference Output 2 Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
8V Reference	B1405 02	B0954 06, B0955 06, B0956 06, B0957 06, B0958 06, B0959 06, B0960 06, B0961 06, B1405 03	B0954 06, B0955 06, B0956 06, B0957 06, B0958 06, B0959 06, B0960 06, B0961 06, B1405 07	-
Left Front Object Sensor Signal	B0954 06	B0954 06	B0954 01	B0954 08, B0954 21
Left Middle Front Object Sensor Signal	B0955 06	B0955 06	B0955 01	B0955 08, B0955 21
Right Middle Front Object Sensor Signal	B0956 06	B0956 06	B0956 01	B0956 08, B0956 21
Right Front Object Sensor Signal	B0957 06	B0957 06	B0957 01	B0957 08, B0957 21
Left Rear Object Sensor Signal	B0958 06	B0958 06	B0958 01	B0958 08, B0959 21
Left Middle Rear Object Sensor Signal	B0959 06	B0959 06	B0959 01	B0959 08, B0959 21
Right Middle Rear Object Sensor Signal	B0960 06	B0960 06	B0960 01	B0960 08, B0958 21
Right Rear Object Sensor Signal	B0961 06	B0961 06	B0961 01	B0961 08, B0961 21
Low Reference	--	B0954 06, B0955 06, B0956 06, B0957 06, B0958 06, B0959 06, B0960 06, B0961 06	--	--

Circuit/System Description

The object sensors are 3 wire sensors that are used to determine the distance between the vehicle and an object of interest. The parking assist control module supplies 8 V to the object sensors via the 8 V reference circuit and provides ground via the low reference circuit. The parking assist control module triggers the sensors in a sequential loop. After each sensor transmits, the parking assist control module uses the sensor echo received through the signal circuit to calculate the distance and position of an object.

Conditions for Running the DTC

•	Vehicle in Service Mode or ON

•	The parking assist is activated. The activation takes place through putting in the reverse gear or through operating the parking assist switch.

Conditions for Setting the DTC

B1405 02

The parking assist control module has detected the 8 V reference circuit is shorted to ground.

B1405 03

The parking assist control module has detected the 8 V reference circuit is less than 6.3 V.

B1405 07

The parking assist control module has detected the 8 V reference circuit is greater than 10.4 V.

Action Taken When the DTC Sets

•	The parking assist is disabled.

•	The driver information centre displays SERVICE PARK ASSIST.

Conditions for Clearing the DTC

The condition for setting the DTC is no longer present.

Reference Information

Schematic Reference

Object Detection Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Object Detection Description and Operation : UVC → UD5

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 Verification

Vehicle in Service Mode, activate the parking assist, observe the scan tool Park Assist Sensor Reference Voltage parameter. The reading should be between 6.3-10.4 V.

Circuit/System Testing

Vehicle OFF, disconnect the harness connector at each of the object sensors.
Start at the B78G Rear Object Sensor - Left Outer, Vehicle in Service Mode, activate the park assist, test for 6.3-10.4 V between the 8 V reference circuit terminal 1 at the object sensor harness connector and ground.

⇒	If less than the specified range, test the 8 V reference circuit for a short to ground. If the circuit tests normal, replace the K41 Front and Rear Parking Assist Control Module.

⇒	If greater than the specified range, test the 8 V reference circuit for a short to voltage. If the circuit tests normal, replace the K41 Front and Rear Parking Assist Control Module.

Install each object alarm sensor harness connector one at a time, checking DTCs after each sensor is connected. Verify DTC B1405 is not set as current.

⇒	If the DTC is set, replace the object alarm sensor that was connected immediately before the DTC set.

Note: Make sure to check front object sensors.

If all circuits test normal, replace the K41 Front and Rear Parking Assist Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

•	Front Parking Assist Alarm Sensor Replacement

•	Rear Parking Assist Alarm Sensor Replacement

•	Control Module References for parking assist control module replacement, programming and set-up