P1EA6
DTC P1EA6 or P1EA7
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 Descriptors
DTC P1EA6
- 14 Volt Power Module Cooling Fan Control Circuit
DTC P1EA7
- 14 Volt Power Module Cooling Fan Enable Circuit
Circuit/System Description
The 14 V power module cooling fan blows air through the 14 V power module to control the temperature of the 14 V power module. The fan is controlled with a pulse-width modulated signal sent from the hybrid/EV powertrain control module 2 to the 14 V power module fan. The longer the duty cycle on the signal the higher the fan speed. Maximum fan speed is 3900 RPM. An enable signal from the hybrid/EV powertrain control module 2 to the 14 V power module fan provides overall control of the fan. When this circuit is high, the fan can operate. The 14 V power module fan provides a hard-wired pulse-width modulated feedback signal to the hybrid/EV powertrain control module 2. During normal operation, this feedback signal provides fan speed information. The 14 V power module fan has some self-diagnostic capability. If it determines there is an internal fault it provides this information on this same feedback circuit instead of speed information.
Conditions for Running the DTC
P1EA6
* The 12 V battery voltage is greater than or equal to 9 V.
* The 14 V power module fan is enabled
P1EA7
The 12 V battery voltage is greater than or equal to 9 V.
Conditions for Setting the DTC
P1EA6
The hybrid/EV powertrain control module 2 has detected an open, short to voltage or short to ground on the 14 V power module cooling fan control circuit
P1EA7
The hybrid/EV powertrain control module 2 has detected an open, short to voltage or short to ground on the 14 volt power module cooling fan enable circuit.
Action Taken When the DTC Sets
DTCs P1EA6 and P1EA7 are type B DTCs.
Conditions for Clearing the DTC
DTCs P1EA6 and P1EA7 are type B DTCs.
Reference Information
Schematic Reference
Hybrid Cooling Schematics Hybrid Cooling Schematics
Connector End View Reference
Component Connector End Views Hybrid/EV Battery Pack X1 A4
Description and Operation
Hybrid Cooling System Description and Operation Hybrid Cooling System 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
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
Ignition ON, with a scan tool, command the 14 V Power Module Fan Command between 10%-90%-10%. Verify that the 14 V Power Module Fan Speed increases and decreases with the command.
Circuit/System Testing
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 (1-877-446-8227) if you have any questions.
1. Ignition OFF, disconnect the harness connector at the G38 14 V power module cooling fan.
2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 ohm between the ground circuit terminal 1 and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Connect a test lamp between the B+ circuit terminal 5 and ground.
4. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 5 and ground circuit terminal 1.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, replace the G38 14 V power cooling module fan.
5. Verify the scan tool Hybrid/EV Battery Pack Coolant Pump Feedback parameter is less than 10%.
• If greater than the specified range, test the signal circuit terminal 2 for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
6. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 4. Verify the scan tool, Hybrid/EV Battery Pack Coolant Pump Feedback parameter is greater than 90%.
• If less that the specified range, test the signal circuit for a short to ground. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
7. Connect a test lamp between the B+ circuit terminal 5 and the control circuit terminal 3.
8. Command the 14 V Power Module Fan ON between 10% and 90% with a scan tool. Verify that a test lamp changes illumination between bright (10%) and dim (90%) between the B+ circuit terminal 5 and the control circuit terminal 3.
• If the test lamp is always dim or does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
• If the test lamp is always bright, test the control circuit for a short to ground. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
9. Connect a test lamp between the enable circuit terminal 4 and ground circuit terminal 1.
10. Command the 14 V Power Module Fan Command ON with a scan tool. Verify that a test lamp illuminates between the enable circuit terminal 4 and ground circuit terminal 1.
• If the test lamp does not illuminate, test the enable circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.
11. Ignition OFF, disconnect the X2 connector at the K114B hybrid/EV powertrain control module 2.
12. Ignition ON, verify that a test lamp does not illuminate between the enable circuit terminal 4 and ground circuit terminal 1.
• If the test lamp illuminates, test the enable circuit for a short to voltage.
13. If all circuits test normal, replace the G38 14 V power module cooling fan.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Accessory DC Power Control Module Cooling Blower Replacement Accessory DC Power Control Module Cooling Blower Replacement
* Control Module References Control Module References for hybrid/EV powertrain control module 2 replacement, programming and setup