ST162 3sge Short Circuit

[TauhuTauhu]

Hi all, this celica which I have just sold is drawing a lil bit of current when its off, draining the battery over night. The current is very small so it doesnt burn the fuse. When i tested the circuit, it seems that it only shorts whn the engine is hot. Checked the thermostat fan swith and that wasnt the problem. What other possible reasons could there be?
It will be a nightmare to trace the wiring and isolate each area to check =/

[Dale]

Alternator and starter are the only things to have power to them when the ignition is off

[allencr]

Alternator and starter are the only things to have power to them when the ignition is off

They are the only things not fused, so testing the fuses should find it, because alt, & starter problems are Rarely draining batteries. Neither the starter or ignition have any more power to them then anything else, while there might be power to the radio, ECU/s, clock, seatbelt/s, airbag/s, brake & warning lights, sensors, accessories, whatever.

Does the battery have enough power to crank for a few seconds, then that's more then enough to test with. Disconnect one battery terminal, either one, to put in a bulb -tungsten lamp- or an amperage meter between the terminal and the battery, wired in 'series'. Depending on haw much or how little the current draw is, a headlamp might be too big and one from an instrument cluster might be too small, to show any difference or handle the amount of amperage.
The brightness or high meter reading will go down when the offending item is disconnected by pulling the fuse or disconnecting it.
ARE YOU SURE that the battery IS OK? Has it been disconnected overnight and then worked well the next day? Is this a recent problem and what have you done/changed/fixed/modified/looked at just before this problem started, wiring/electrical/battery related or not?

[TauhuTauhu]

the battery is new, literally brand new.

Weird thing is, i tested the 3 main fuse filaments. I disconnected the main fuse from the battery terminal, connected a bulb between the filament to +ve terminal of batt, 1 by 1 and they were all drawing current when the ign was off.

After that i tried testing the wires going into the main fuse 1 by 1 and there is this white wire thts is shorting. It only happens whn the engine is hot. Dont know what that wire is and where it splits to.

on the main fuse holder, there are 3 wires going in. 1 side has 2 wires (red+blck strips, and white), the other side has another wire. It is the white one which draws current. Any idea where tht wire goes to?

I have not been driven the car for months until i got it a new battery just last week.

[Mos]

I currently have an ST162 loom apart. Do you have the version with the ALT/AM1/AM2 fuses on the battery terminal (early) or inside the fusebox (late)?
I think you're talking about the AM1 fuse, which provides the alternator sense wire, amongst many things. Disconnect the alternator and see if it stops. Repeat the test you did pulling out all the other smaller fuses.
If it only does it when the engine is hot I'd tend to think it's running through the engine loom and the alternator wires do that.
Mos.