Q: Lexus IS250 2007 166K miles. No problems ever. Power failing; will run if all systems off; smells like ozone. Thinking alternator

asked by on January 07, 2017

Car runs completely normal until the climate control is turned on. Then, after a few minutes, electric starts pitching with various computer outputs like "CHECK 4WD" and the compass not working, dimming of things, etc. Turn them off and then it goes back to normal in about 2-3 min. of idling.

My car has 166500 miles.
My car has an automatic transmission.

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Hi there. I believe you may be correct about the alternator. Perform a visual inspection of the valve cover area above the alternator for oil. If there is oil leaking onto the alternator, this will need to be corrected as a new alternator will fail from oil contamination. Otherwise, this definitely sounds like an alternator failing and should be properly tested to confirm. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several technicians available that can assist you with an electrical problems inspection.

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