P2CEF · メーカー技術情報

LOTUS · 2026-09-30

Emira 4-Cylinder vehicles only - Issue 3 includes updated information on thermostat the testing method and replaces version 2 of this bulletin published on 05.08.2026. Diagnosing medium temperature engine coolant thermostat operation to prevent unnecessary thermostat replacement. The information in this bulletin is intended as a procedure that should be performed if a 4-cylinder Emira has generated Diagnostic Trouble Code (DTC) P2CEF00 Auxiliary Thermostat “A” Stuck Open (see image for thermostat location). Generation of DTC P2CEF00 may also result in: - Illumination of the Malfunction Indicator Lamp (MIL). - A low coolant temperature warning message being displayed. IMPORTANT: Do not continue with the procedure in this bulletin If DTC P2CEF00 has NOT BEEN generated. ACTION If DTC P2CEF00…

LOTUS · 2026-03-11

Diagnosing medium temperature engine coolant thermostat operation to prevent unnecessary thermostat replacement. The information in this bulletin is intended as a procedure that should be performed if a 4-cylinder Emira has generated Diagnostic Trouble Code (DTC) P2CEF00 Auxiliary Thermostat “A” Stuck Open (see image for thermostat location). Generation of DTC P2CEF00 may also result in: - Illumination of the Malfunction Indicator Lamp (MIL). - A low coolant temperature warning message being displayed. IMPORTANT: Do not continue with the procedure in this bulletin If DTC P2CEF00 has NOT BEEN generated. 1. If the thermostat MOVES FREELY when heated and cooled, then refit the original thermostat with a new gasket and refill the engine with new antifreeze/coolant. 2. If the thermostat DOES…

MERCEDES-BENZ · 2025-10-13

Complaint Customer states that the CEL is lit in the instrument cluster. Various codes may be active/stored: Stored in N3/10 in model series 206, 254 or 232: P012800 - The coolant temperature is below the coolant thermostat specified temperature. and/or P01169D - Malfunction in coolant temperature sensor 1. Under temperature in the component or system. For model series 177, 118, 247 in n3/10 (only valid for M139.980 facelift (code 9U8)): P2CEF00 - Electrical fault or open circuit in coolant thermostat. and/or P011685 - Malfunction in coolant temperature sensor 1. There is a signal above the permissible limit. Cause Debris in the coolant system Remedy An updated thermostat must be installed. Order the correct thermostat part number for your application: CLA45/GLA45 with SA Code 9U8: A 139…