P0540 - Intake Air Heater A Circuit

The ECM detected a fault in intake air heater A circuit.

Code Overview

The ECM detected a fault in intake air heater A circuit.

Common Causes

• Failed intake air heater element
• Relay, fuse, or wiring issue
• Connector or control fault

Diagnostic Steps

1. Inspect heater circuit wiring and connectors
2. Check fuse, relay, and power feed
3. Test heater element resistance if applicable

Likely Repairs & Cost Guides

Use test results to confirm the fault before pricing the repair.

Related OBD Codes

Browse the closest code-family pages when the same fault pattern often shows up nearby.

Next Steps

Move from the code to a diagnosis path, then into repair pricing once the fault is confirmed.