Posted before, 2006 4.0 sport, Batt light on after new Batt and 2 rebuilt alt. Wires have not been chewed, messed with, etc. If there is power on both sides of the fuse in the dash fuse block, would that not mean the problem was between there and the dash panel, or am I just being hopeful ? I am starting to think about pulling the fuse block in the engine bay, but if the problem is farther towards the dash, why bother? What is the physical path that the grey "batt" light wire takes after leaving the alt plug? Thanks for any input, I'm about ready to fix it with electrical tape, OVER THE LIGHT !! rsbhunter

Sat bump

@Rsbhunter I can't say physically where that Grey wire routes but looking at the Wiring Schematic... I see a White, Grey, and a Yellow/Red wire leaving that port on the alternator. The Grey wire goes to a connector labeled EA1/EA2 (depending on which Engine you have). The other side of that connector continues as a Grey wire to IC4 ("Instrument Panel Wire and Engine Room Main Wire (Left Kick Panel)"), then to a Junction connector J18(A) From there it splits with one Grey wire going to the body ECU port 14. The other Grey wire leaving J18(A) goes to another Junction Connector labeled J8(A) and leaves that to go to port 16 of the "Combination Meter" C8(A). From there it exits as a "R-L" wire (Red / Lavender?) to a 7.5 amp fuse, that turns into a Black-Red wire to the Ignition Switch.

Adding some additional information on locations of the junctions mentioned above:
Starting from the alternator the EA1/EA2 connector appears to just be a "Connector Joining Wire Harness" the location is listed as "(Under the Engine room R/B)". pg 44/45 shows this under the fuse box near the engine.

The IC4 connector is listed as being located "Instrument Panel Wire and Engine Room Main Wire (Left Kick Panel)". Page 46 shows it 2nd one down, left side in a cluster of 5 connectors near the bottom of the dash behind the drivers door side kick panel.

Junction connector J18(A) appears to be tucked up behind the Instrument cluster Looking at Page 38 the lots of pointers here so hard to tell exactly where in the cluster.

Body ECU port 14 is under the dash looks like between the steering column and above the brake pedal.

The other Grey wire leaving J18(A) goes to another Junction Connector labeled J8(A)/J9(B) which is also tucked up behind the Instrument cluster Looking at Page 38

The "Combination Meter" port 16 C8(A) is not far from J8(A) still behind the cluster but a bit down and towards the drivers door. per Page 37.

From there it exits as a "R-L" wire (Red / Lavender?) to junction block connector 1G which appears to be an inline 4 wire plug going into the Engine room relay box to a 7.5 amp fuse and out via connector 1D as the Black-Red wire to the Ignition Switch IG2 6 That goes through the switch to port "7 AM2" which is a Red Wire going to a 30 amp AM2 fuse or fusible link then on to the battery and Ground.


I hope this description helps you. I tried to upload a copy of the pages but can't seem to add them here.

Boort

Have you checked the grounds? There is one from the battery to the inner fender. There may be others to check. Also back in the day there was a fusible link at the starter. I'm not sure if the 4Runners have them but if one of those melted it would cause a no start or cause a charging problem.