What Does P008C Mean?
The ECM has detected an open circuit condition in the fuel cooler pump control circuit. The fuel cooler pump is used primarily in diesel and some performance gasoline vehicles to cool fuel before it returns to the tank or enters the injection system. An open circuit means the pump cannot be energized. The driver may not notice immediate symptoms but fuel temperature may rise, leading to reduced power and increased emissions under sustained load.
Common Causes
35%
Broken or disconnected wiring in the fuel cooler pump circuit
30%
Failed fuel cooler pump motor (open winding)
20%
Blown fuse or faulty relay in the fuel cooler pump circuit
10%
Corroded or damaged connector at the fuel cooler pump
5%
ECM driver circuit failure preventing pump activation
Diagnostic Steps
1
Locate the fuel cooler pump (typically near the fuel tank or along the fuel line routing) and check the electrical connector for secure connection, corrosion, or damage.
2
Check the fuel cooler pump fuse and relay. Replace the fuse if blown and verify the relay clicks when commanded on. If the fuse blows again immediately, there is a short in the pump or wiring.
3
Disconnect the pump and measure resistance across the motor terminals. An open-loop (OL) reading confirms a failed pump motor. Typical pump resistance is 1–10 ohms depending on design.
4
With the pump disconnected, check for continuity in the supply and ground wires from the ECM/relay to the pump connector. An open circuit in either wire will prevent operation.
5
If wiring is intact and the pump tests good, command the pump on via scan tool and verify the ECM is providing the activation signal using a test light or DVOM at the pump harness.
Estimated Repair Cost
$150 - $600
Parts + labor, varies by vehicle and location
The ECM has detected an open circuit condition in the fuel cooler pump control circuit. The fuel cooler pump is used primarily in diesel and some performance gasoline vehicles to cool fuel before it returns to the tank or enters the injection system. An open circuit means the pump cannot be energize...
The most common cause of P008C (Fuel Cooler Pump Control Circuit Open) is: Broken or disconnected wiring in the fuel cooler pump circuit
Typical repair costs for P008C range from $150 to $600, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Generally safe to drive under normal conditions. The primary risk is elevated fuel temperature during sustained high-load operation (towing, hot weather, highway driving), which can reduce power and increase emissions. Avoid heavy-load driving until repaired, especially in hot climates.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P008C 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
Fuel System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
