Lexus Es350 Parts And Lexus Es350 Accessories
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What a Code P0505 of your Lexus ES350 Check Engine Light Means
Having an illuminated Check Engine Light is never a cause for celebration. As much as it hates being the bearer of bad news, the Check Engine Light (CEL) is only trying to do its job, which is to warn you that something is wrong with the engine of your Lexus ES350 and that maybe you should check it out before it worsens. It\'s really quite simple, but the number of people who ignore their CEL is alarmingly still a large one.
How the Check Engine Light Works
Once the Check Engine Light comes on, a diagnostic trouble code (DTC) is sent to the Engine Control Unit (ECU). Even after the light goes out, the control module will still store the DTC or even several trouble codes. When you take your Lexus ES350 for inspection, retrieval of the DTC(s) would be needed so the problem can be properly diagnosed. This is always the first step in knowing which direction to go. There could be so many reasons why the Check Engine Light is illuminated, but right now, the focus is on the P0505 code.
Unfolding the Code P0505
A P0505 code generally means that the IAC (Idle Air Control) motor of your Lexus ES350 has gone bad. The IAC valve is responsible for controlling the engine\'s idle speed, which is done by allowing only a certain amount of air around the throttle plate. A shutter acts as a door for the bypass air passageway. The idle speed rises when the IAC lets in more air around the throttle plate.
Meanwhile, a Powertrain Control Module (PCM) uses the IAC valve in keeping the idle speed correct, even with changing demands from the engine. Another responsibility of the PCM is to ensure that the IAC circuits are giving off correct voltage; otherwise it will set the P0505 code.
Aside from the Check Engine Light coming on, another sign that there is something wrong with your IAC motor is a sudden stalling of your engine. A broken IAC motor could definitely affect the idle speed of your Lexus ES350.
The Best Solution
There are cases where resetting of the ECU of the Lexus ES350 does the trick, and so does cleaning the throttle body, but keep in mind that these cases are very rare. These solutions might cost less, but they are also difficult to accomplish. As with anything, if you are unsure of the necessary steps, paying an expert to do it would still be the best option.
Checking for leaks or loose connections in the induction system should also be done. There are possibilities that these leaks or loose connections are the actual culprit for the illuminated Check Engine Light. However, the common causes for a P0505 are still either it being due to damage of an IAC motor connecter or that one or some of the IAC circuits have shorted. A permanent solution would be to just go ahead and replace the whole throttle body assembly, a unit where the IAC motor belongs to. Although having it replaced would cost more, it should be done if you want to avoid further problems.