Check Engine Light/Trouble Code Due to Stuck Open Thermostat on Mazda 3

Submitted by Vehicle Owner · Apr 1, 2025

Published by RepairPal

Problem overview

Some vehicles may experience Check Engine Light illumination with a trouble code indicating the thermostat is stuck open. The thermostat will need to be replaced with a modified one and there is a software update for the Powertrain Control Module (PCM).

84 people reported this problem

38 comments

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Mazda 3 vehicles with this problem

8 model years affected

Average mileage: 92,361 miles

(8,800 - 165,000)

Repairs related to this problem

Thermostat Replacement

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Check Engine Light/Trouble Code Due to Stuck Open Thermostat on Mazda 3

Problem overview

Mazda 3 vehicles with this problem

Need a diagnosis? Trust our Mazda experts.

Search for another problem

Ask our experts about your Mazda.

Need a diagnosis? Trust our Mazda experts.

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