What Does P0C4D Mean?
The voltage in the hybrid battery coolant pump power supply circuit is above the acceptable threshold. This indicates excessive voltage reaching the pump, which can damage the pump motor and control electronics.
Safety Warning
Excessive voltage can damage pump motor and electronics, potentially causing pump failure and battery overheating. May also indicate charging system fault that could damage other vehicle electronics.
Common Causes
35%
Faulty voltage regulator causing overcharging condition
25%
Failed pump relay with incorrect voltage routing
20%
Wiring fault causing connection to higher voltage source
15%
Control module voltage sensing circuit failure
5%
Damaged power distribution module routing incorrect voltage
Diagnostic Steps
1
Step 1: Measure voltage at pump power supply terminal (should not exceed 16V with engine running)
2
Step 2: Check charging system output voltage at battery and compare to specifications (typically 13.5-14.8V)
3
Step 3: Test pump relay for correct voltage output and proper contact operation
4
Step 4: Inspect wiring for incorrect connections or damage causing high voltage exposure
5
Step 5: Verify voltage sensing circuit at control module for accurate readings
Estimated Repair Cost
$200 - $1,000
Parts + labor, varies by vehicle and location
The voltage in the hybrid battery coolant pump power supply circuit is above the acceptable threshold. This indicates excessive voltage reaching the pump, which can damage the pump motor and control electronics.
The most common cause of P0C4D (Hybrid Battery Pack Coolant Pump Supply Voltage Circuit High) is: Faulty voltage regulator causing overcharging condition
Typical repair costs for P0C4D range from $200 to $1,000, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Excessive voltage can damage pump motor and electronics, potentially causing pump failure and battery overheating. May also indicate charging system fault that could damage other vehicle electronics.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P0C4D to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Hybrid Battery Cooling System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
