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?s re: checking oil and inverter

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by bfh, Jan 1, 2005.

  1. bfh

    bfh New Member

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    Hello.

    The 2005 Prius owner's manual recommends checking the engine oil's level with the engine at operating temperature (but not running).

    I've always checked engine oil when the engine is cold.

    Can someone please explain Toyota's rationale for this?

    Also, exactly what is the inverter in the Prius and what does it do?

    Thanks in advance.
     
  2. Frank Hudon

    Frank Hudon Senior Member

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    checking the oil when warm gives a better indication of the level Hot oil expands and cold oil contracts. Hot hight level cold lower. The inverter takes the battery voltage which is direct current and converts it to alternating current to drive the motor(MG2). It also takes the output from the MG1 (generator) and converts it to dc to go thru the converter attached to the bottom of the inverter and charge the auxillary 12Volt battery and it also lowers the voltage from MG1 (500volts) to charge the High Voltage battery(200 volts). It's the box on the right hand side of the engine compartement.
     
  3. bfh

    bfh New Member

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    Frank:

    Many thanks for the helpful reply.

    However, the idea of checking the oil level while the engine is hot still makes little sense to me.

    If you measure the oil when it's hot, then you're getting an indication of the oil level while some oil is in other parts of the engine rather than an indication of the oil level in the oil pan.

    If the level is low and you add oil, then when the engine is cold, wouldn't you have too much oil in the oil pan?