P240C — Evaporative Emission System Leak Detection Pump Heater Control #

Note: The wording of this code may differ depending on the vehicle manufacturer (OEM). Always check your service manual for the most accurate description for your application.

• Evaporative Emission System Leak Detection Pump Heater Control Circuit (Chrysler, Dodge, Jeep, RAM)
• EVAP System Leak Detection Pump Heater Control Malfunction (Volkswagen, Audi)
• EVAP Leak Detection Pump Heater Control Circuit Low (BMW, Mini)

Summary of DTC P240C #

The P240C diagnostic trouble code (DTC) points to a problem with the leak detection pump heater control circuit in the vehicle’s Evaporative Emission Control (EVAP) system. The leak detection pump (LDP) is a component responsible for pressurizing the EVAP system to check for leaks in fuel vapor containment. Some modern vehicles use a heater element in the LDP to ensure accurate operation, especially in cold conditions. When the Engine Control Module (ECM) detects an abnormality—such as voltage outside of the expected range or an open/short circuit—in the heater control circuit, it triggers code P240C. This code may not cause immediate drivability issues, but it often points to a breakdown in emissions system integrity.

Frequent Symptoms for Code P240C #

While the P240C code is primarily related to emissions and the EVAP system, some symptoms may be subtle or go unnoticed by the driver. However, in certain cases, you may experience:

• Illuminated Check Engine Light (CEL)
• Mild fuel odor around the vehicle, especially near the fuel tank or rear
• Failed emissions test or readiness monitor not setting
• Slightly reduced fuel economy (rare)
• No noticeable drivability issues in most cases

Most Probable Causes for Code P240C #

The P240C code is usually caused by electrical or component faults within the leak detection pump heater circuit. Here are the most common reasons, listed in order of likelihood:

1. Faulty leak detection pump heater (the heater element itself has failed)
2. Wiring issues (open circuit, damaged, or corroded wires/connectors in the heater control circuit)
3. Blown fuse (if the heater is fused separately)
4. Faulty relay or control module (rare, but possible in some models)
5. ECM/PCM software issue (very rare, but possible with certain OEMs)

Step-by-Step Diagnostic for P240C #

Addressing the P240C code requires a logical, stepwise approach. Here’s how a technician or advanced DIYer would proceed:

• Verify the code using a professional scan tool to confirm P240C is active and record any related codes.
• Inspect the EVAP leak detection pump and its heater wiring for obvious damage, corrosion, or loose connectors.
• Check the heater circuit fuse (if applicable) for continuity; replace if blown and investigate why.
• Test the leak detection pump heater resistance using a digital multimeter; compare to OEM specs (often 10–30 ohms—always consult service data).
• Backprobe the circuit to verify the ECM/PCM is providing correct voltage and ground to the heater circuit during self-test or activation.
• Test for continuity and shorts between the ECM/PCM and the leak detection pump heater connector.
• Clear the code and perform a drive cycle or EVAP test to confirm successful repair.

Possible Repairs for P240C #

Depending on which cause you identify, the following repairs may resolve the P240C code:

• Replace faulty leak detection pump (especially if the heater element is part of the assembly and tests out of spec)
• Repair or replace damaged wiring/connectors in the heater circuit (corrosion, rodent damage, or pinched wires are common offenders)
• Replace blown fuse and address root cause (short circuit or failed component)
• Replace faulty relay or ECM/PCM (rare, only if confirmed by testing and all other causes have been ruled out)

Can You Drive with Code P240C? #

Yes, you can usually drive with code P240C for a limited time, as it does not directly impact engine performance or safety. However, prolonged driving with this code may cause your vehicle to fail emissions testing and could allow fuel vapors to escape, which is environmentally harmful. It is best to address the issue promptly, especially if your vehicle inspection is due soon.

Vehicles Most Commonly Affected by P240C #

While P240C can appear on a wide variety of vehicles equipped with advanced EVAP systems, it is most often reported on:

• Chrysler, Dodge, Jeep, and RAM models (especially 2005–2020)
• Volkswagen and Audi (2005–2015)
• BMW and Mini (2007–2016, particularly with turbocharged engines)
• Some Toyota and Lexus hybrids

Common Mistakes & Best Practices for P240C #

Misdiagnosis of P240C is not uncommon, largely due to the hidden nature of the EVAP system. To avoid headaches and unnecessary parts replacement, keep in mind:

• Don’t just clear the code without a proper inspection—the issue will likely return.
• Always check wiring and connectors before replacing expensive components.
• Verify with a wiring diagram to ensure you’re testing the correct circuit and not confusing the heater circuit with the pump motor circuit.
• Use OEM parts when replacing the leak detection pump for best compatibility and reliability.

Express FAQ for DTC P240C #

Q: Will P240C cause my car to run poorly or stall?
A: No, P240C is an emissions system code and does not directly affect engine operation or drivability in most cases. However, it will trigger your check engine light and may prevent inspection readiness monitors from completing.

Q: How urgent is it to fix a P240C code?
A: While not an emergency, you should repair the issue within a reasonable timeframe to avoid emissions failures and potential vapor leaks. Ignoring it for months could cause other EVAP-related issues to go undetected.