P2559 low

Engine Coolant Level Sensor Circuit Intermittent

The P2559 code means the vehicle's onboard diagnostic system has detected: Engine Coolant Level Sensor Circuit Intermittent. This is a low severity code.

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Keep driving?: Yes, but fix soon
DIY difficulty: easy
Estimated cost: $0 - $150 (parts and labor)

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Common Symptoms

Sporadic low coolant warnings
Coolant level light flickers
Check engine light intermittent
Coolant level reading jumps erratically

Probable Causes (Ranked by Likelihood)

Loose coolant level sensor connector Very High
Coolant splashing causing intermittent readings High
Sensor float sticking intermittently Moderate
Corroded wiring connection at sensor Low

Step-by-Step Diagnostic Procedure

Check sensor connector for looseness
Verify coolant level is not borderline between high and low marks
Clean sensor probe and float mechanism
Inspect wiring connector for corrosion

Frequently Asked Questions

Could my coolant level just be borderline?

Yes. If the coolant is right at the minimum mark, normal fluid movement while driving can cause the sensor to toggle between high and low, triggering intermittent warnings.

Is topping off the coolant a fix for P2559?

If the level is borderline, topping off may resolve the intermittent warnings. If the level is clearly full, the sensor or wiring has an intermittent fault.

How do I clean the coolant level sensor?

Remove the sensor from the reservoir and clean the probe and float with a mild solvent. Remove any scale or debris that could interfere with float movement.