Charge Air Cooler Coolant Pump Control Circuit High
The P023C code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the control circuit of the charge air cooler (CAC) coolant pump. This pump circulates coolant through the intercooler to reduce intake air temperature. A high voltage signal typically points to a short to power, a faulty pump, or a wiring issue.
1. Most Common Causes
- Short circuit of the pump control wiring to battery voltage (B+)
- Internal failure of the pump control transistor or driver within the ECM
- Intercooler coolant pump with altered internal resistance or mechanically seized
- Damaged connector or wiring with bent pins or corrosion causing a high voltage reading
- Faulty pump control relay if applicable to the vehicle design
2. Symptoms You Will Notice
- Check Engine Light on
- Reduced engine performance or power loss
- Possible overheating of charge air cooler
- Increased intake air temperatures
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to verify P023C and check for related codes.
Step 2: Visually inspect the CAC coolant pump connector and wiring for damage or corrosion.
Step 3: Test the pump control circuit voltage with a multimeter; compare to manufacturer specs.
Step 4: Check pump resistance and operation; replace if faulty.
Step 5: Clear codes and test drive to confirm repair.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with a high voltage circuit can cause further electrical damage or pump failure, leading to reduced engine performance and potential overheating.
How much does it cost to fix?▼
Typical repair costs range from $50 to $150 for parts and labor, depending on the cause. A pump replacement may cost more if the pump itself is faulty.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.