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DTC codes / P2Dxx · Hybrid propulsion / P2D6E

P2D6EBattery Charging System Positive Contactor D Control Circuit Low

P2D6E indicates that the battery charging system's positive contactor control circuit, specifically for contactor D, has been detected by the control module as having a low voltage condition. The computer monitors the control circuit for the contactor that connects the high-voltage battery to the charging system and sets this code when the circuit voltage falls below the expected threshold, which can prevent the contactor from closing and disrupt charging.

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

Symptoms you may notice

  • Illumination of the battery/charging system warning light or a dedicated service vehicle soon message.
  • The vehicle may fail to start or enter a ready-to-drive state because the high-voltage battery contactor does not close.
  • Charging system may not operate, leaving the high-voltage battery depleted over time.
  • In some cases, the vehicle may run normally with no noticeable performance change besides the warning light.
  • A no-crank or no-start condition may occur if the contactor control circuit is completely open or shorted to ground.
  • Other systems powered by the high-voltage battery, such as electric climate control, may become inoperative.

Common causes, most likely first

  1. A short to ground or open circuit in the positive contactor D control wire, often due to chafed insulation or a broken conductor.
  2. Corroded, loose, or damaged electrical connectors at the contactor or control module, causing high resistance or intermittent connection.
  3. A failed positive contactor D coil, which may be open or shorted internally and draw excessive current or none at all.
  4. A faulty control module driver circuit that cannot supply the proper voltage or current to the contactor coil.
  5. Water intrusion or contamination in the contactor housing or connector, leading to corrosion and low circuit voltage.
  6. A blown fuse or relay that supplies power to the contactor control circuit, though this is less common on dedicated control lines.

How to diagnose and fix it

  1. Verify the code with a scan tool and check for any related codes in the charging system and high-voltage battery modules.
  2. Inspect the contactor D control circuit wiring and connectors for visible damage, corrosion, or loose pins, and repair as needed.
  3. Measure the control circuit voltage at the contactor connector with the key on and compare to the manufacturer's specification to confirm the low condition.
  4. Test the contactor coil resistance and compare to specification; replace the contactor if it is open or shorted.
  5. Check the control module output signal with an oscilloscope or bidirectional scan tool to confirm the driver is functioning correctly.
  6. If the control module is suspected, perform a pinout and continuity test between the module and contactor before replacing the module.
  7. After repairs, clear the code and perform a charging system test to verify the contactor closes and the charging system operates normally.

Contactor Control Circuit Checks You Might Overlook

  • A low voltage on the control circuit can be caused by a short to ground anywhere along the wire, not just at the contactor, so a thorough wiggle test and continuity check from end to end is essential.
  • The contactor may be commanded open by the control module due to a separate fault, such as an over-temperature or isolation fault, which can set this code as a secondary effect rather than a direct circuit failure.
  • Some vehicles use a smart contactor with an integrated driver, and a low control circuit code may indicate a failed internal driver rather than a wiring issue, requiring replacement of the entire contactor assembly.
  • A weak or failing 12-volt auxiliary battery can cause erratic control module behavior and set this code, so always check the 12-volt system before condemning high-voltage components.
  • After replacing a contactor or control module, some vehicles require a learn or adaptation procedure for the contactor to be recognized, and skipping this step can cause the code to return immediately.

Can I keep driving with P2D6E?

Do not continue driving with this code if the vehicle fails to start or shows a high-voltage system warning, as the contactor may not close and the vehicle could lose power unexpectedly. If the vehicle still drives, limit use to reach a safe location or service center, and avoid relying on the charging system until the fault is repaired.

Tools that help

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

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