01 How Automatic Transmissions Decide When to Shift • 02 Drivers Are Left Stunned After Discovering The Real Purpose… • 03 ELECTRIC PARKING BRAKES (EPB): COMPONENTS, WORKING PRINCIPL… • 04 Charging Anxiety vs. Green Future: Why Americans Aren't Buy… • 05 Is the Land Rover Defender 2022 Worth a Trial? • 06 Feeling the Heat? Troubleshoot Your Car's AC System Problem… • 07 Automotive Abbreviations: A Guide for Car Enthusiasts • 08 Car Won't Start or Running Rough? Don't Ignore a Faulty Cam… • 09 6 Simple Ways to Tell the Difference When Buying a Car • 10 Fueling Your Journey: A Comprehensive Guide to the Fuel Sup… •

DTC codes / P0Exx · Hybrid propulsion / P0E64

P0E64Battery Charger A Enable Circuit Intermittent/Erratic

P0E64 indicates that the powertrain control module (PCM) has detected an intermittent or erratic signal on the enable circuit for battery charger A, which is typically part of the high-voltage charging system in hybrid and electric vehicles. The PCM monitors the enable circuit for consistent voltage when the charger is commanded on, and this code sets when the signal momentarily drops out or fluctuates beyond an acceptable threshold.

SystemPowertrain
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyProfessional
AreaHybrid propulsion

Symptoms you may notice

  • Illumination of the check engine light or service vehicle soon message
  • Often no symptoms besides the warning light, especially if the fault is intermittent
  • Reduced or absent high-voltage charging, leading to a low state of charge
  • The vehicle may fail to start or enter a reduced power mode if the auxiliary battery is not maintained
  • Inconsistent charging performance noticed through the charge indicator or range estimate
  • Possible stored history codes in other modules related to charging or battery management

Common causes, most likely first

  1. Loose, corroded, or damaged electrical connectors at the battery charger enable circuit
  2. Chafed or broken wiring in the enable circuit, often due to vibration or routing issues
  3. Faulty battery charger assembly with an internal intermittent connection
  4. Poor ground connection for the charger or its control module
  5. PCM software glitch or internal driver issue causing erratic enable signal
  6. Water intrusion or contamination in connectors causing intermittent shorts
  7. Aftermarket accessories improperly tapped into the enable circuit

How to diagnose and fix it

  1. Inspect and clean all connectors related to the battery charger enable circuit, checking for corrosion or loose pins
  2. Perform a wiggle test on the wiring harness while monitoring the enable circuit signal with a scan tool or multimeter
  3. Check the enable circuit for continuity and resistance, looking for opens or high resistance
  4. Verify the ground connections for the charger and control module are clean and tight
  5. Swap the battery charger with a known-good unit if the fault persists and wiring is confirmed good
  6. Reprogram or update the PCM software if a known issue exists for intermittent enable signals
  7. Clear codes and road test to confirm the repair, monitoring live data for any recurrence

Intermittent enable faults often misdiagnosed

  • A common oversight is replacing the battery charger when the real problem is a chafed wire hidden inside a loom, so always perform a thorough harness inspection before condemning the charger.
  • The code can be set by a momentary voltage spike or drop on the enable circuit that does not affect charging performance, so do not assume the charger is failing based solely on this code.
  • Some vehicles use the enable circuit to wake the charger from a sleep state, and a weak auxiliary battery can cause erratic signals that mimic a circuit fault.
  • Aftermarket alarm or remote start installations often tap into the enable circuit, introducing intermittent connections that set this code.
  • The PCM may set P0E64 as a companion code to other charging system faults, so always check for related codes before focusing on the enable circuit alone.

Can I keep driving with P0E64?

If the warning light is on but the vehicle drives normally and charging appears consistent, you can drive short distances to a repair shop, but avoid relying on the vehicle for long trips. If charging is intermittent or the vehicle enters reduced power mode, stop driving and seek professional diagnosis to prevent being stranded.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage