P1EB9
DTC P1EB9
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 P1EB9
- High Voltage Energy Communication Bus Enable Circuit
For symptom byte information, refer to Symptom Byte List Symptom Byte List.
Diagnostic Fault Information
Circuit/System Description
The Hybrid Powertrain Control Module 2 activates the high voltage energy management communication enable circuit when the vehicle is on. This circuit wakes up the devices for high voltage energy bus communication.
Conditions for Running the DTC
* The system voltage is between 9-16 V.
* The vehicle power mode master requires serial data communication to occur.
Conditions for Setting the DTC
The Hybrid Powertrain Control Module 2 detects a fault in the high voltage energy management communication enable circuit.
Action Taken When the DTC Sets
DTC P1EB9 is a type A DTC.
Conditions for Clearing the DTC
DTC P1EB9 is a type A DTC.
Diagnostic Aids
Short to ground will also set multiple no communication codes for devices on high voltage energy serial data bus.
Reference Information
Schematic Reference
* Data Communication Schematics [1][2]Electrical Diagrams
* Control Module References Programming and Relearning
Connector End View Reference
Component Connector End Views Hybrid/EV Battery Pack X1
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 Programming and Relearning for scan tool information
Special Tools
EL-48900 - HEV Safety Kit
For equivalent regional tools, refer to Special Tools Tools and Equipment.
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 includes the following steps:
* 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 15 meters (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 with leather protectors at all times when working with the high voltage battery assembly, whether the system is energized or not.
Failure to follow the procedures may result in serious injury or death.
Danger: The Volt Battery Pack will utilize an exchange program. Please consult the most recent revision of bulletin/PI #PIP4841, available in Service Information (SI), for a list of approved Volt Battery Pack service procedures. Components that may be removed and serviced without exchanging the complete battery pack are identified in the bulletin/PI. Please contact the GM Technical Assistance Center if you have any questions.
Note: Use the schematics to determine which devices are on the K114B Hybrid Powertrain Control Module 2 terminal 48 X2 high voltage energy management communication enable circuit. Use the connector end views to identify the B+, ignition, and high voltage energy management communication enable circuit terminals for each of those devices.
1. Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 meters (9.8 feet) away from vehicle. Disconnect the X2 harness connector at the K114B Hybrid Powertrain Control Module 2. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for greater than 100 ohms, but less than infinite resistance, between the high voltage energy management communication enable circuit terminal 48 X2 and ground.
• If 100 ohms or less
Refer to Testing the High Voltage Energy Management Communication Enable Circuits for a Short to Ground.
• If infinite resistance
Test for an open/high resistance in the high voltage energy management communication enable circuit.
• If greater than 100 ohms and less than infinite resistance
3. Vehicle in Service Mode.
4. Verify that a test lamp illuminates between each B+ circuit terminal and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Vehicle OFF.
2. Test for less than 2 ohms in the B+ circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, verify the fuse is not open and there is voltage at the fuse.
• If the test lamp does not illuminate and the circuit fuse is open
1. Vehicle OFF.
2. Test for infinite resistance between the B+ circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the K114B Hybrid Powertrain Control Module 2.
• If the test lamp illuminates
5. Vehicle in Service Mode.
6. Verify that a test lamp illuminates between each ignition circuit terminal and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Vehicle OFF.
2. Test for less than 2 ohms in the ignition circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, verify the fuse is OK and there is voltage at the fuse.
• If the test lamp does not illuminate and the circuit fuse is open
1. Vehicle OFF.
2. Test for infinite resistance between the ignition circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the K114B Hybrid Powertrain Control Module 2.
• If the test lamp illuminates
7. Replace the K114B Hybrid Powertrain Control Module 2.
Testing the High Voltage Energy Management Communication Enable Circuits for a Short to Ground
1. Perform the High Voltage Disabling procedure. Refer to High Voltage Disabling High Voltage Disabling.
2. Reconnect the 12 V battery.
3. Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 meters (9.8 feet) away from vehicle. Disconnect the harness connector at an easily accessible device that shares the K114B Hybrid Powertrain Control Module 2 terminal 48 X2 high voltage energy management communication enable circuit. It may take up to 2 minutes for all vehicle systems to power down.
4. Test for less than 100 ohms between the K114B Hybrid Powertrain Control Module 2 high voltage energy management communication enable circuit terminal 48 X2 and ground.
• If 100 ohms or greater
Replace the device that was just disconnected.
• If less than 100 ohms
5. Repeat step 3 until all devices on the K114B Hybrid Powertrain Control Module 2 high voltage energy management communication enable circuit terminal 48 X2 have been disconnected.
6. Repair the short to ground on the high voltage energy management communication enable circuit.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
Control Module References Programming and Relearning for device replacement, programming and setup.