Engine Controls - SES Lamp ON/DTC 2EF4 Set
SI B 12 15 05Engine Electrical Systems
September 2005
Technical Service
SUBJECT
N62: Map Thermostat Faults 2EF4/279B
Model
E65/E66 with N62 up to 03/05
E60/E63/E64 with N62 up to 09/05
Situation
"Service Engine Soon" light is illuminated. Fault code 2EF4 (on vehicles with DME ME9.2.2 produced from 09/04), or 279B - "Map cooling thermostat mechanically stuck" are stored in DME.
Engine does not over heat and map thermostat operates properly.
CAUSE
Possible increased contact resistance between thermostat temperature sensor, engine wiring harness and DME connector.
Correction
On a customer complaint basis only, replace engine wiring harness and thermostat temperature sensor. Clear the DME connector.
PARTS INFORMATION
WARRANTY INFORMATION
Covered under the terms of the BMW New Vehicle Limited Warranty.
For the appropriate labor operation and labor allowance refer to the KSD system.
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