Motor Electronics Coolant Pump Control Circuit Low
The P0A06 code indicates that the powertrain control module (PCM) has detected a low voltage condition in the control circuit of the motor electronics coolant pump. This pump is responsible for circulating coolant through the inverter and motor electronics in hybrid/electric vehicles. A low circuit voltage typically points to a wiring issue, a faulty pump motor, or a problem with the PCM itself. If left unaddressed, it can lead to overheating of the motor electronics, reduced performance, or potential damage to the hybrid system.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Overheating of motor electronics or inverter
- Reduced hybrid system performance
- Possible warning messages on dashboard
2. Most Common Causes
- Faulty power electronics coolant pump (internal short)
- Control circuit wiring shorted to ground
- Pump power supply circuit open or high resistance
- Damaged, corroded, or loose connectors at pump or control module
- Internal pump driver failure in PCM/inverter ECM
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the coolant pump connector and wiring for damage or corrosion.
Step 3: Test the pump control circuit voltage with a multimeter (should be near battery voltage when commanded on).
Step 4: Check pump resistance and compare to specs; replace if out of range.
Step 5: If wiring and pump are okay, test PCM output or reprogram as needed.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the motor electronics may overheat, causing reduced performance or damage. Short trips to a repair shop are acceptable if the vehicle is not overheating.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, but can be higher if the pump needs replacement (parts and labor may total $200-$500).
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.