No head/tail lights or turn signals, squirrel chewed ground at J4

The remote lock hasn't worked in the 18 months I've had the truck.
I think that's the antenna, and the other end is cut, wrapped around drivers visor. There was an oval plastic piece on the end, but it's been cut off for a while now.

 

I think I see it, but I can't get a tester in there or figure out how to unclip it.
If it was bad, I'd replace the fuse box/control unit?

 

I mean now that I see there is aftermarket stuff tied in we need to be sure that isn't tapped into the headlight circuits.

 

Unplugging the exposed red wire didn't change anything.

I jumped 3 to 5 at the head relay, and get low beams only if I wiggle the DIM relay around, switch does nothing.
With the HEAD jumped and DIM removed, the DIM pins 1 and 3 get correct power, but DIM 4 and 5 show ground, whereas 2/ground slot shows nothing ever.

 

HEAD relay has no ground, but does have 12V power at slot 5 (correct), slot 2 (wrong) and 2.71V power from 1/ground (very wrong).
DIM relay (with HEAD removed, no jumper wire in HEAD), has 9V of power to the ground slot and 12V of ground in both headlight slots.

So are we trying to figure out where the ground connection for the HEAD relay is shorted?
The only way I see for power to get to the DIM ground slot when HEAD is removed is if the 5 HEAD slot is shorted to the 1 HEAD slot, and the power is leaking thru the ECU?

 

That's wrong, it shows 9V power, not ground, with high beams on, zero with low beams, with HEAD relay in OR out. 10V with flasher lever pulled back.

 

2 and 5 should have constant power.

We need to make sure that the alarm system or something else isn't tapped into the relay control circuits before condemning the Body ECU.

 

I disconnected the white plug to the left of the stripped red wire, and now the turn signals work. Can't seem to get the blue connector loose.
However, I don't think I'll be able to remove the alarm system myself.
There seems to be a lot of electrical tape and little red donut splicers that cut into the wire they connect to- those seem pretty suspicious.

Are those red donut things testable?

 

I've removed a bunch of aftermarket alarm/remote start systems, typically isn't much to it. Pull all the taps out of the wires they are tapped into and repair any wires that are cut.

Assuming you mean T-Taps, I hate those things but unfortunately thats what alot of aftermarket stuff installed with.

 

Yep, those are the red things, they look pretty annoying.

How is the alarm set up? Is there a connector that came with the truck that needs to be plugged back in somewhere after the alarm box and all taps are removed?

 

I mean every alarm system is different but most aftermarket ones are just spliced in, the Toyota accessory ones use some factory connectors.

Find the tag on the control box to see what you have then google the install instructions and reverse it.

 

Well this is driving me nuts.
It isn't-
the alarm
the ECU
the ECM
the headlight/turn stalk switch.

Changed the ECU, did nothing. Got an actual mechanic to disconnect the alarm, nothing changed, he said have the dealer reprogram the ECM. I bought one programmed for my VIN, installed it, truck seems to run smoother with new ECM, and now low beams come on when I pull back to flash highs.
New stalk/switch changed nothing.
Still the same 9.46 volts of power at headlight relay ground pin (1), while (2) and (5) show correct 12.4V.
The green wire going to (from?) the headlight switch/stalk clip *also* shows the same V of power as the headlight relay ground, 9.46.

I looked inside the engine compartment fuse box, didn't see anything wrong, but that thing is VERY full of wires- how the heck would you find a shorted wire or change that fuse box out for a new one?
From the headlight switch, it looks like the green wire goes off to the passenger side/ECM, but it's hard to be sure.

 

Not sure why we changed ECM, it has nothing to do with anything we are chasing here?

We were suspecting the Body ECU/Junction Box but you said you changed that?

That's the control wire for the Right turn, the multifunction switch grounds it to tell the Turn Signal Flasher to turn on the Right turn signal.

Do we still have low voltage at the IG1 No 2 Fuse?

 

I took it to someone capable of dealing with the alarm, he said the ECM should be reprogrammed by a dealer, which sounded expensive so I switched in a new one at home. Truck seems to run smoother, maybe the mileage will improve, but yes, it had nothing to do with the headlights.

Yes, a replacement ECU changed things least of all.

The voltage at IG1#2 is 12.2 with key on, 11.9 with truck running. Voltage at cig lighter is 12.2 key on, 13.4 truck running.
IG1#2 only tested low the first time, it has been normal(?) since.

With the IG1#2 fuse out, there's a fast clicking from behind ECU only when headlight stalk is clicked forward for highs, not when pulled back for flashing.

 

So the headlights still do NOT work on Low?
But they do work on High?

 

I'll have to look back through this tonight and see if we missed anything.
You changed the junction box too correct? I'm assuming you did since the Body ECU is on the back of it.

 

The parking lights work when the stalk is in low only, at the first position, but 2nd position, low beams on is no head or parking lights.
Highs do not work at all, I get low when I pull back the stalk to flash highs.
I believe wiggling the headlight relay makes low beams flicker.

Yes, changed the whole thing.

 

It sounds like you don't have control of the to the body ecu.
The control wire is the pink wire.

I'd like to see if you have a ground signal at the pink wire to the ECM when you turn the head lights on.
There are a few way to check it.

A test light or voltage meter.

The IJ1 connector may be the easiest to get to....
But I don't like starting in the middle of a circuit.
I'd rather start at the end, and work backwards until I find the open (issue).

Give me a bit. I'll try to write up a "check" list.

 

Body ECU
B5 pin #17 - (Pink wire) = Path to ground when Headlights ON.
B5 pin #16 - (Red/White wire) = Path to ground when Flash ON.

1I Connector
Pin #9 - (Red/Green wire) = Path to ground when Flash ON - And when High Beams ON.

IJ Connector
Pin #1 - (Pink wire) = Path to ground when Headlights ON
Pin #10 - (Red/White wire) = Path to ground when Flash ON.

 

B5 pin #17 - (Pink wire) = Path to ground when Headlights ON.
there is no wire in that spot

B5 pin #16 - (Red/White wire) = Path to ground when Flash ON.
is green/black or black/green. NO ground or power showing, very small, but looks rusty or burnt.

1I Connector
Pin #9 - (Red/Green wire) = Path to ground when Flash ON - And when High Beams ON.
this one is good, 12.2V of ground on both, and R/G.

IJ Connector
Pin #1 - (Pink wire) = Path to ground when Headlights ON
NO ground or power, and is sort of beige
Pin #10 - (Red/White wire) = Path to ground when Flash ON.
NO ground or power, and is black/red

So it seems neither pink wire you are looking for is pink in this truck? Technically, one is beige and one is missing.