The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 20, 2010
Filed:
May. 16, 2008
Keiji Wakahara, Inazawa, JP;
Keiji Wakahara, Inazawa, JP;
DENSO CORPORATION, Kariya, JP;
Abstract
A plug of a power cord of a block heater, which is mounted to a cylinder block of an engine, is connected to a household power receptacle to energize the block heater during an engine stoppage in cold climate. Thus, an engine coolant is kept warm to prevent freeze. Existence/nonexistence of the energization to the block heater during the engine stoppage is determined based on a behavior of coolant temperature or a behavior of engine rotation speed immediately after an engine start. If it is determined that the energization to the block heater exists, abnormality diagnosis of a cooling system is prohibited or a condition for the abnormality diagnosis is corrected and estimation coolant temperature is corrected.