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99 LS400 strange power failure?

 
Old 03-25-19, 05:59 AM
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Stereorob
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Default 99 LS400 strange power failure?

runs/drives like a dream. everything was fine yesterday and today, however it appears to have had some kind of power failure overnight. lost all memory presets. radio, navi settings and was in pacific region (default when power is out between battery changes etc., seats, clock, trip ODO mpgs and elapsed time all back to zero.

car fired right up. no warning lights, false codes or anything else. battery is only a few months old and terminals are surgically clean. clock was at 4:00 and i was in the car at 7:30, so it probably happened around 3am.

just a weird fluke or could there be something up?
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Old 03-25-19, 08:14 AM
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billydpowe
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If I read your post right, that is scary... you might retell your experience with a little more detail (mileage and such)
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Old 03-25-19, 08:40 AM
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Originally Posted by billydpowe View Post
If I read your post right, that is scary... you might retell your experience with a little more detail (mileage and such)

just lost all its memory. indicates a power failure to me. everything is fine with the car. everything feels great. just lost all its memory. what would cause that?
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Old 03-25-19, 08:50 AM
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I worry about that there may be some extra impedance at connections or the starter is about failing. I'd monitor the voltage drop of related lines when starting up using an oscilloscope which has a memory function.
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Old 03-25-19, 09:19 AM
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Originally Posted by Yamae View Post
I worry about that there may be some extra impedance at connections or the starter is about failing. I'd monitor the voltage drop of related lines when starting up using an oscilloscope which has a memory function.
ill try that. i work at a dealership so i have full access to the entire history of the car, as well as techstream. threw it in a bay the second i got to work this morning, ran it thru a scanner, nothing suspect at all. car was insanley well kept. previous owner spent $27,500 on the car over the years and replaced anything immediatly that even started to look funky or out of spec. nicest well kept one ive ever had. doesnt leak a drop, no clunks knocks sounds or funny smells, car absolutley rockets up on the highway and feels like its riding on air. everything silky smooth. did notice a little watter collecting in the right turn signal lamp lens. maybe something getting wet and pissing off the ECU?
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Old 03-25-19, 02:14 PM
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Default Connector issues causing body ecu problems

You have power, just not to all systems?

Body ECU..or you may have water on connector buss area in lower right passenger kick panel due to water spilloverfrom plugged sunroof drains....this was my issue.
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