Went out to move the truck to the driveway and found it now totally dead. I put a battery in it 3 days before I changed out the rear taillight assemblies.
So first I need to figure out what is killing the battery.
Joy...
BlueManLou,
We got this. Primary failure categories to consider:
* Good battery is a victim of an aftermarket alarm installed by the PO.
* Good battery is victim of parasitic draw on far side of fuses.
* Good battery is victim of parasitic draw from one or more damaged diodes in
the alternator's bridge rectifier. (
diodes in bridge rectifiers)
* Bad battery self-discharging. One or more of the 6 cells are self-discharging
due to conductive muck on bottom interconnecting plates where they shouldn't be.
(Muck = plate material shed due to age, rough roads, discharged battery froze, etc.)
****
Recovery plan:
1) Anything aftermarket installed in the truck? If so, temporarily disconnect, and see if
truck will now work at least twice the observed failure interval. If this fixes it, then
delete the aftermarket item. Or upgrade it to a more battery-friendly version.
2) If step #1 wasn't applicable or didn't fix the issue, then set up ammeter in series
(note most meters have spendy 10A internal fuse, so consider running ammeter through a
8A fused jumper) and measure the milliamp current draw when the truck is OFF.
Record the value, and if it's high, then start pulling fuses, starting at the IP (Instrument
Panel) fuse block. Most will make no difference, but when you hit the correct fuse the
multimeter reading will drop appreciably. Write down which fuse it is, look up that
fuse's power distribution circuit in the Service Manual, and then to figure out is the
milliamps being drawn are normal for that option, or is it excessive? This may require
some quality rabbit hole time. :0)
3) If none of the fuses provided the Aha moment, then temporarily disconnect the
alternator and see if that fixes the parasitic draw? If so, then remove alternator
and have it tested for free at the parts store. Usually one or more blown diodes
will be picked up by the test station and be flagged as a fail.
4) Still no joy? Fully charge the battery, and then disconnect it from the truck.
If the truck was discharging over, say, a 5 day stretch, then leave the battery
disconnected for the same time interval, reconnect it, and then see if the
truck will or will not start.
****
Sounds like more work than it really is. Maybe do the battery check first, and
then depending on how that goes, then dive into the truck itself. (ie: Battery
as victim, truck as perpetrator.) Of course the converse could be true (truck
is victim, battery as perpetrator) ...but given the stream of replacement parts
I'm thinking the odds are truck: 51, battery: 49.
Hmmm...you just posted a photo, looks like you are already off to the races?
Let us know what you find.
Cheers --