Volkswagen ID.4

P0A78

Caution

Drive Motor "A" Inverter Performance

Severity
Caution
Category
Motor
Code Type
EV-Specific
Applicable Regions
US, EU, Global

What does P0A78 mean?

Fault code P0A78 means "Drive Motor "A" Inverter Performance". It is an EV/Hybrid-specific diagnostic trouble code (DTC) in the powertrain system, classified as "motor" with a severity level of "caution". This is a lower-severity code that should be monitored. Have it checked at your next regular service appointment. This code is defined by the SAE J2012 / ISO 15031-6 standard and applies to OBD-II compliant vehicles sold in the US, EU, and other global markets. [Ford EV-specific: HV Battery Over Voltage. Applies to: Mustang Mach-E, F-150 Lightning, E-Transit] [Volkswagen EV-specific: High Voltage Battery Over Voltage. Applies to: ID.3, ID.4, ID.5] [Volkswagen Group (MEB) EV-specific: High Voltage Battery Over Voltage. Applies to: VW ID.3, VW ID.4, VW ID.5, VW ID.7]

Possible Causes

  • Electric motor winding fault
  • Inverter control module failure
  • Position sensor misalignment or failure
  • Overheating due to cooling system issue

Recommended Actions

  1. 1 Monitor the situation and service at your next scheduled visit
  2. 2 Schedule a diagnostic scan at an authorized service center
  3. 3 Avoid driving at high speeds until inspected

This code applies to all vehicles. View generic P0A78 information →