LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2022 >> Hummer EV >> Repair and Diagnosis >> Electrical >> Motors, Switches, Relays >> Hybrid/EV Energy Storage - Diagnostic Information And Procedures (1 Of 2) >> Diagnostic Information and Procedures >> DTC P3061 >> Circuit/System Testing

Circuit/System Testing

WARNING:

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.

High Voltage System Bus Diagnosis

  1. Disable the high voltage for every high voltage component. High Voltage Disabling .
  2. NOTE:

    This test is performed at the module high voltage terminals with the expected test measurement initially several Meg ohms and slowly varying to a steady value. You must measure with a high-impedance digital multimeter (DMM). DO NOT use the EL-50772  Insulation Multimeter to measure insulation resistance.

  3. Print the Complete High Voltage System schematic to assist you in your testing. Refer to Drive Motor Battery System Description to obtain the system schematic.
  4. Print the Component Resistance Test Table below.
  5. NOTE:
    • You may test components in any order.
    • The component should be disconnected from all other high voltage components when testing.
    • Test between the high voltage terminals, not to chassis ground.
    • Meter test probe polarity to module terminal polarity will effect results, refer to the Component Resistance Test Table 
    • Print the Component Resistance Test Table and record your testing results.
  6. Test and record the minimum resistance between each components high voltage terminals as indicated by the Component Resistance Test Table.
  7. Replace any component that tests less than the MINIMUM expected resistance and repeat Circuit/System Verification.
  8. If all components test within DMM Expected Results, leave all high voltage connectors disconnected and refer to High Voltage Bypass Testing below.
Component Resistance Test Table

Components Digital Multimeter (DMM) Test Point Digital Multimeter (DMM) Expected Results Actual Result
NOTE:

High Voltage MUST be disabled prior to testing any components. Refer to Circuit/System Verification and Circuit/System Testing.

G1HV Air Conditioning With Motor Compressor DMM positive to X1-1, DMM negative to X1-2 OL initial, 10K Ω minimum  
DMM positive to X1-2, DMM negative to X1-1 several meg initial, 10K Ω minimum  
E54V Hybrid/Electric Vehicle Coolant Heater DMM positive to X1-1, DMM negative to X1-2 OL initial, 10K Ω minimum  
DMM positive to X1-2, DMM negative to X1-1 several meg initial, 10K Ω minimum  
T18 Battery Charger DMM positive to X2-1, DMM negative to X2-2 several meg initial, 10K Ω minimum  
DMM positive to X2-2, DMM negative to X2-1 several meg initial, 10K Ω minimum  
K107A Drive Motor 1 Control Module DMM positive to X2-1, DMM negative to X2-2 3.5M Ω initial, 10K Ω minimum  
DMM positive to X2-2, DMM negative to X2-1 1.5M Ω initial, 10K Ω minimum  
K107B Drive Motor Control Module 2* DMM positive to X2-1, DMM negative to X2-2 3.5M Ω initial, 10K Ω minimum  
DMM positive to X2-2, DMM negative to X2-1 1.5M Ω initial, 10K Ω minimum  
K107C Drive Motor Control Module 3* DMM positive to X2-1, DMM negative to X2-2 3.5M Ω initial, 10K Ω minimum  
DMM positive to X2-2, DMM negative to X2-1 1.5M Ω initial, 10K Ω minimum  
*As applicable to Vehicle Option Content

High Voltage Bypass Testing

  1. GM5905627Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    The following procedure enables high voltage (HV) while high voltage connectors are disconnected. Always observe the following:

    • Wear your Personal Protection Equipment at all times while handling HV connectors.
    • ONLY perform this procedure if directed by the High Voltage System Bus Diagnosis procedure to do so. If you replaced a component during High Voltage System Bus Diagnosis, do not perform this High Voltage Bypass Testing.
    • You should have disabled high voltage (HV) and disconnected all HV components during High Voltage System Bus Diagnosis.

    With high voltage disabled, identify the A4 Hybrid/Electric Vehicle Battery Pack high voltage connectors X2 (3), X6 (2), and X7 (1), and disconnect them if not already disconnected. Refer to High Voltage Disabling . Cover the exposed high voltage connectors with UL listed, or equivalent, insulation tape rated at a minimum of 600 V on both the module and harness sides.

  2. Reconnect ALL high voltage connectors throughout the vehicle EXCEPT the A4 Hybrid/Electric Vehicle Battery Pack-DC connectors X2 (3), X6 (2), and X7 (1). These are the smaller HV connectors around the A4 Hybrid/Electric Vehicle Battery Pack.
  3. Engage the High Voltage Service Lock Out (HVSL) and reconnect the 12V battery.
  4. Vehicle ON, clear the DTC information. Vehicle OFF and wait 10 minutes.
  5. NOTE:

    With the A4 Hybrid/Electric Vehicle Battery Pack HV connectors X2, X6 and X7 disconnected you may set other DTC (s).

  6. Vehicle ON, verify DTC P3061 does not set.
    • Go to next step: If DTC P3061 is not set 
  7. Turn the vehicle OFF and wait 10 minutes.
  8. Open the High Voltage Service Lockout (HVSL).
  9. NOTE:

    From this step on you will reconnect components one at a time until DTC P3061 sets.

  10. While wearing your Personal Protection Equipment remove the electrical tape from the A28 Hybrid/Electric Vehicle Battery high voltage connectors X6 and reconnect.
  11. Close the High Voltage Service Lockout (HVSL).
  12. Vehicle ON, verify DTC P3061 does not set.
    • If the DTC sets 
    1. Perform High Voltage Disabling  for servicing at all the components.
    2. E54V Hybrid/Electric Vehicle Coolant Heater - Replace - High Voltage Battery Heater Module Replacement
    • Go to next step: If the DTC does not set 
  13. Turn the vehicle OFF and wait 10 minutes.
  14. Open the High Voltage Service Lockout.
  15. While wearing your Personal Protection Equipment remove the electrical tape from the A4 Hybrid/Electric Vehicle Battery Pack high voltage connector X7 and reconnect.
  16. Close the High Voltage Service Lockout.
  17. Vehicle ON, verify DTC P3061 does not set.
    • If the DTC sets 
    1. Perform High Voltage Disabling  for servicing at all the components.
    2. G1HV Air Conditioning With Motor Compressor - Replace - Air Conditioning with Motor Compressor Replacement
    • Go to next step: If the DTC is not set 
  18. Perform High Voltage Disabling  for servicing at all the components.
  19. T18 Battery Charger - Replace - Battery Charger Replacement