Service Information

Volt

DTC P16B7

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 Descriptor

DTC P16B7 00: Electric A/C Compressor Control Module Wake-Up Circuit Performance

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Accessory Wake Up Serial Data 2	P16B7, U016B*	U016B*	U016B*	-
* Other DTCs may set with this fault

The accessory wake-up serial data 2 circuit is energised by the hybrid powertrain control module 2 to immediately activate the A/C compressor connected to this circuit when the body control module (BCM) signals the hybrid powertrain control module 2 that serial data is required.

Conditions for Running the DTC

•	The system voltage is greater than 10.25 V.

•	The A/C compressor is awake.

•	Vehicle ON.

•	The A/C compressor receives a serial data message from hybrid powertrain control module 2 and "Propulsion System Active" is TRUE for 500 ms continuously.

Conditions for Setting the DTC

The A/C compressor detects a fault in the wake-up circuit.

Action Taken When the DTC Sets

DTC P16B7 is a type B DTC.

Conditions for Clearing the DTC

DTC P16B7 is a type B DTC.

Diagnostic Aids

Short-circuit to earh may set multiple no communication codes for high-speed GMLAN control modules.

Reference Information

Schematic Reference

•	Data Communication Schematics

•	Control Module References

Connector End View Reference

Component Connector End Views

Description and Operation

Data Link Communications 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 Verification

Verify that DTC P06E4 is not set.

⇒	If the DTC is set, refer to DTC P06E4 .

Circuit/System Testing

Note: Use the schematic to identify the control modules B+, ignition, earth, communication enable and serial data circuit terminals.

Vehicle OFF, disconnect the X1 harness connector at the G1 A/C compressor.
Vehicle in Service Mode, verify that a test lamp illuminates between the wake-up circuit terminal 2 X1 and earth.

⇒	If the test lamp does not illuminate, test the circuit for a short-circuit to earth or open-circuit/high resistance. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.

Vehicle OFF, verify that a test lamp does not illuminate between the wake-up circuit terminal 2 X1 and earth.

⇒	If the test lamp illuminates, test the circuit for a short to voltage. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.

If all circuits test normal, replace the G1 A/C compressor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for control module replacement, programming and setup