P278E: Kick Down Switch Circuit Intermittent/Erratic
The P278E code indicates that the powertrain control module (PCM) has detected an intermittent or erratic signal from the kick down switch circuit. This switch is typically located near the accelerator pedal and signals the transmission to downshift for maximum acceleration when the pedal is fully depressed. An intermittent fault can cause unpredictable transmission behavior, such as delayed or harsh downshifts, and may be triggered by a faulty switch, wiring issues, or a loose connection.
01. Most Common Causes
- Faulty kick down switch
- Damaged or corroded wiring/connectors in the switch circuit
- Intermittent short or open in the circuit
- Loose or poor electrical connection
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Transmission fails to downshift when accelerator is fully depressed
- Delayed or harsh downshifts
- Reduced acceleration performance
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for any related codes.
Step 2: Visually inspect the kick down switch and its wiring for damage, corrosion, or loose connections.
Step 3: Test the switch continuity with a multimeter; replace if faulty.
Step 4: Check the circuit for shorts or opens using a wiring diagram and multimeter.
Step 5: Clear the code and test drive to verify repair.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is generally not recommended to drive with this code as it can cause unpredictable transmission behavior, potentially leading to unsafe driving conditions. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150, including parts (switch) and labor. Diagnostic fees may be additional.