Hello y'all, new here this is my intro post to the forum. Just purchased a new-to-me 2011 LX570 with 123k miles on it. Bought it from a fairly popular online auction site I won't name because unsure it violates any rules.
It is a stock truck, no aux battery, no winch, no fridge no accessories really using any power besides a dashcam while the car is on connected to the 12v socket. Bought it about two weeks ago, so I don't know its history besides what was on the listing and carfax.
Previous owner had with a Group 24F AGM in it, which I've since learned is the wrong group for these anyway (should be 27F). This battery died a week into driving it. Despite the gague reading it was above 14v.
Replaced it with a Toyota TrueStart 27F. And the battery light came on right away, the alternator seems to be charging it weakly, the AGM higher voltage may have been tricking the gague staying high and battery light away... ?
Behavior has been intermittent. Sometimes the light is on at startup with no charging at all, then it kicks in after an incline or once I'm up to highway speed and settles around 13.4V. Other times it clears on its own after a highway run and sits around 13.8v.
Last night was the first time I'd driven it after dark, so the first time the headlights were actually on.
- Engine off: 12.59V
- Running, no headlights: 13.44V
- Running, headlights on: 12.44V
- Battery light never went out the whole drive
- Around 70 degrees out if that matters for any temperature sensor I heard about.
That 12.44 is below resting voltage, so it's discharging while running.
Haven't been able to reach the B+ post to compare against the battery, measured at the battery post for all testing and/or terminal clamps.
Questions for the group:
1. Does this read as an alternator that's been slowly dying and may need replacing?
2. Brushes or regulator, or high resistance somewhere in the charging circuit? The load-dependent collapse is what makes me wonder about a connection rather than the alternator itself.
3. Anyone chased this on a 200 and found the charge cable or 180A fuse instead of the alternator?
4. Could parasitic draw be the culprit, haven't done any real testing on this yet.
5. Any trick to getting at B+ without pulling the fan and shroud?
6. Could connectors on the alternator be loose or need some sanding and reconnection, there is corrosion since this was a snow climate vehicle.
Any input is highly appreciated, other than this this car has been a dream come true and a goal I had for a very long time. Posting a picture of it, all I've done is put on some stock Tundra TRD Pro wheels on it. It already had a sensor lift.
It is a stock truck, no aux battery, no winch, no fridge no accessories really using any power besides a dashcam while the car is on connected to the 12v socket. Bought it about two weeks ago, so I don't know its history besides what was on the listing and carfax.
Previous owner had with a Group 24F AGM in it, which I've since learned is the wrong group for these anyway (should be 27F). This battery died a week into driving it. Despite the gague reading it was above 14v.
Replaced it with a Toyota TrueStart 27F. And the battery light came on right away, the alternator seems to be charging it weakly, the AGM higher voltage may have been tricking the gague staying high and battery light away... ?
Behavior has been intermittent. Sometimes the light is on at startup with no charging at all, then it kicks in after an incline or once I'm up to highway speed and settles around 13.4V. Other times it clears on its own after a highway run and sits around 13.8v.
Last night was the first time I'd driven it after dark, so the first time the headlights were actually on.
- Engine off: 12.59V
- Running, no headlights: 13.44V
- Running, headlights on: 12.44V
- Battery light never went out the whole drive
- Around 70 degrees out if that matters for any temperature sensor I heard about.
That 12.44 is below resting voltage, so it's discharging while running.
Haven't been able to reach the B+ post to compare against the battery, measured at the battery post for all testing and/or terminal clamps.
Questions for the group:
1. Does this read as an alternator that's been slowly dying and may need replacing?
2. Brushes or regulator, or high resistance somewhere in the charging circuit? The load-dependent collapse is what makes me wonder about a connection rather than the alternator itself.
3. Anyone chased this on a 200 and found the charge cable or 180A fuse instead of the alternator?
4. Could parasitic draw be the culprit, haven't done any real testing on this yet.
5. Any trick to getting at B+ without pulling the fan and shroud?
6. Could connectors on the alternator be loose or need some sanding and reconnection, there is corrosion since this was a snow climate vehicle.
Any input is highly appreciated, other than this this car has been a dream come true and a goal I had for a very long time. Posting a picture of it, all I've done is put on some stock Tundra TRD Pro wheels on it. It already had a sensor lift.
