The P240B: Evaporative Emission System Leak Detection Pump Heater Control Circuit Low refers to an issue where the sense circuit for the leak detection pump heater in the evaporative emission system is receiving low voltage. This can lead to ineffective leak detection, increased emissions, and potential failure to pass emissions tests.
P240B – Quick Overview
| Code | Information |
|---|---|
| Meaning | P240B: Evaporative Emission System Leak Detection Pump Heater Control Circuit Low |
| Is it serious? | Yes, low voltage in this circuit can lead to ineffective leak detection and increased emissions. |
| Possible causes | – Low voltage in the leak detection pump heater control circuit – Faulty leak detection pump heater – Wiring or connector issues |
| How to diagnose? | – Measure voltage in the leak detection pump heater control circuit – Inspect and test the leak detection pump heater and wiring – Check connectors for faults |
P240B Meaning
The P240B: Evaporative Emission System Leak Detection Pump Heater Control Circuit Low code indicates that the control circuit for the heater of the leak detection pump in the vehicle’s evaporative emission system is experiencing lower than normal voltage. The heater ensures that the pump operates efficiently, especially in cold conditions, by preventing condensation and ensuring proper functionality. Low voltage in this circuit can prevent the heater from operating correctly, leading to ineffective leak detection, increased emissions, and potential environmental harm. Additionally, this issue can cause the vehicle to fail emissions inspections.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Measure voltage in the leak detection pump heater control circuit | Use a multimeter to measure the voltage in the leak detection pump heater control circuit. Compare the readings to the manufacturer’s specifications to determine if the voltage is indeed low. | Multimeter, Wiring Diagram |
| Inspect and test the leak detection pump heater and wiring | Visually inspect the leak detection pump heater for any signs of damage or wear. Test the heater’s functionality using a diagnostic tool to ensure it operates correctly. Inspect the wiring for any signs of fraying, corrosion, or breaks that could cause low voltage. | Multimeter, Diagnostic Tool, Visual Inspection Tools |
| Check connectors for faults | Inspect all connectors related to the leak detection pump heater control circuit for secure connections and signs of corrosion or damage. Clean or replace connectors as necessary to ensure a proper electrical connection. | Multimeter, Connector Cleaning Tools |
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