P240A — Evaporative Emission System Leak Detection Pump Heater Control #

Note: The code label for P240A can differ depending on manufacturers.

• P240A: Evaporative Emission System Leak Detection Pump Heater Control Circuit/Open (Ford, GM, Toyota)
• P240A: EVAP System Leak Detection Pump Heater Control Circuit Low (BMW, Mercedes-Benz)
• P240A: Evaporative System Leak Detection Pump Heater Malfunction (Volkswagen, Audi)

Code summary for P240A #

P240A is a diagnostic trouble code (DTC) that indicates the Powertrain Control Module (PCM) has detected an issue with the heater control circuit for the Evaporative Emission (EVAP) System’s Leak Detection Pump (LDP). The EVAP system is designed to trap fuel vapors from the fuel tank and prevent them from escaping into the atmosphere. The leak detection pump, sometimes equipped with a heater, helps the system check for leaks by pressurizing the EVAP system. P240A specifically points to a problem with the electrical control of the pump’s heater, not the pump operation itself. This code is most often related to wiring issues, failed heaters, or connector problems rather than an actual leak in the system.

Frequent symptoms for code P240A #

When P240A is stored in your vehicle’s memory, symptoms can range from minimal to obvious, depending on your car and its emissions strategy. Generally, the driver may notice one or more of the following:

• Check Engine Light illuminated (most common)
• EVAP system not completing readiness monitors
• Slight decrease in fuel efficiency (rare)
• Failed emissions test
• No noticeable drivability concerns in most cases

Likely causes for code P240A (from most to least common) #

Diagnosing P240A starts with understanding what can interrupt the heater circuit for the leak detection pump. The most probable issues are:

1. Faulty leak detection pump heater
2. Broken or corroded wiring to the heater circuit
3. Loose, dirty, or damaged electrical connectors
4. Blown fuse (if circuit is fused separately)
5. PCM/ECU software issue or rare internal failure

Step-by-step diagnostic process for P240A #

Proper diagnosis of a P240A code ensures you don’t replace unnecessary parts. Here’s a recommended approach:

• Step 1: Confirm code with a scan tool and check for other related DTCs (especially any EVAP system or circuit codes).
• Step 2: Visually inspect wiring and connectors at the leak detection pump and along the harness for damage, corrosion, or disconnection.
• Step 3: Test the heater circuit for continuity and proper voltage with a multimeter per your OEM wiring diagram.
• Step 4: Check the fuse(s) associated with the EVAP system and heater circuit.
• Step 5: Using a scan tool with bi-directional control, command the pump heater ON/OFF and observe circuit response.
• Step 6: If all wiring checks out, bench-test the leak detection pump heater for resistance and operation.
• Step 7: If no faults are found, consider PCM/ECU software updates or rare module failure.

Possible repairs for code P240A #

Once you’ve pinpointed the fault, here are the most common repair actions for P240A:

• Repair or replace damaged wiring to the leak detection pump heater
• Clean or tighten corroded/loose connectors at the pump or harness junctions
• Replace the leak detection pump assembly (if heater element is failed and not serviceable separately)
• Replace blown fuse (if applicable) and identify underlying cause
• Update PCM/ECU software or replace module if all hardware checks pass and TSBs (Technical Service Bulletins) recommend it

Is it safe to drive with code P240A? #

Yes, but with limitations: Driving with P240A will not typically cause immediate drivability problems or damage your engine. However, your EVAP system may not test for leaks properly, which means you could fail an emissions inspection. If your region requires regular emissions checks, you’ll want to resolve this code before your next test. Extended driving with any emissions system fault is not recommended, as it can mask other issues.

Vehicles most affected by code P240A #

P240A is most commonly seen on modern vehicles equipped with advanced EVAP systems, especially those from the following manufacturers:

• Toyota/Lexus/Scion (2005+)
• Volkswagen/Audi (2006+)
• BMW/MINI (2007+)
• General Motors (Chevrolet, GMC, Buick, Cadillac, 2005+)
• Ford/Lincoln/Mercury (2008+)
• Mercedes-Benz (2007+)

Other makes may store this code, but it’s particularly prevalent among those listed above.

Frequent mistakes & best practices for P240A #

A few common pitfalls can slow down or complicate the repair process for this code. Here’s what to watch for:

• Replacing the leak detection pump without checking wiring: Often, the issue is a simple wiring fault.
• Ignoring Technical Service Bulletins (TSBs): Some OEMs have released TSBs addressing this code with software updates or revised parts.
• Overlooking the basics: Always check fuses, connectors, and grounds before replacing expensive components.
• Assuming it’s a fuel cap or EVAP leak issue: P240A points to a heater control fault, not a vapor leak.

Quick FAQ for code P240A #

Here are answers to some of the most common questions about this code:

• Q: Will clearing the code fix P240A?
  A: No. Clearing the code may turn the light off temporarily, but the fault will return unless the underlying issue is fixed.
• Q: Can I replace just the heater or do I need the whole pump?
  A: It depends on your vehicle. On many models, the heater is integrated into the leak detection pump and not serviceable separately. Check your OEM parts catalog for specifics.