Diesel Data: Automotive Repair

P16B7




DTC P16B7

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions 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/System Description

The wake up signal circuit is energized 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 above 9 V.
* The ignition is ON.
* The A/C compressor receives serial data message from engine control module 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.
* The control module is never signaled; therefore the specific subsystems will not function.

Conditions for Clearing the DTC

DTC P16B7 is a type B DTC.

Diagnostic Aids

Short to ground may set multiple no communication codes for high speed GMLAN control modules.

Reference Information
Schematic Reference

* Data Communication Schematics [1][2]Electrical Diagrams
* Control Module References Control Module References

Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1 A4
Description and Operation

Data Link Communications Description and Operation Description and Operation
Electrical Information Reference

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

Scan Tool Reference

Control Module References Control Module References for scan tool information
Special Tools

EL-48900 - HEV Safety Kit



Circuit/System Verification

Verify that DTC P06E4 is not set.

If the DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

Circuit/System Testing

Danger: Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.


The High Voltage Disabling procedure will perform the following tasks:


* Identify how to disable high voltage.

* Identify how to test for the presence of high voltage.

* Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.


Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:


* Safety glasses with appropriate side shields when within 50 feet of the vehicle, either indoors or outdoors.

* Certified and up-to-date Class "0" Insulation gloves rated at 1000V with leather protectors.


- Visually and functionally inspect the gloves before use.

- Wear the Insulation gloves at all times when working with the high voltage battery assembly, whether the system is energized or not.


Failure to follow the procedures exactly as written may result in serious injury or death.


Danger: This diagnostic has NOT been validated on-vehicle. Follow all safety protocol and utilize all appropriate personal protective equipment to ensure your safety. Failure to follow the procedures exactly as written may result in serious injury or death.


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

1. Perform the High Voltage Disabling procedure before proceeding with this diagnostic. Refer to High Voltage Disabling High Voltage Disabling.
2. Reconnect the 12 V battery.
3. Ignition OFF, disconnect the X1 harness connector at the G1 A/C compressor.
4. Ignition ON, verify that a test lamp illuminates between the wake up circuit terminal 2 X1 and ground.

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

5. Ignition OFF, verify that a test lamp does not illuminate between the wake up circuit terminal 2 X1 and ground.

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.

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

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Control Module References Control Module References for control module replacement, programming and setup