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

With multimeter set so battery shows 12.4V, batt(-) to those 3 all show zero volts.
Is that the correct setting on the meter? The more sensitive settings show some...noise?

 

Oops, I thought I mentioned it in passing, haven't seen any chewed wires at all, it would have had to done some contortions to get at a hidden spot, but my head is larger than a squirrel. Anything I could check with a mirror?

 

Yes, we want to see less than 0.5v of voltage drop between battery negative and any ground point on the vehicle with the circuit loaded (things on that circuit turned on).

So do the same check at the ECU ground pin.

 

1H pin 18 seems to be zero too, with key on, highbeams on, connector in, but not sure if the probe was getting in there far enough.
Should I test the clip when unplugged?
Have to get back to work, will return shortly.

 

I'm having trouble getting at 1H pin 18, but there's no power leaking and solid ground at J1, pin 4?
Should I try harder for 1H/18? That's J1 at the bottom here, I cut off the 1.

Edit: Got to 1H pin 18, good solid ground there too.

 

There is something weird going on with ECU B5. Going by that spreadsheet from earlier, there are extra wires in slots that should be blank?

Smaller pins, 13-26 go like this, tested with multimeter:
Pin 13- Green wire, correct spot, 10.4V Tail Light Switch Signal from IJ1 Pin 8
14- White, right spot, 12.2V Headlight Relay Control Signal to IA1 Pin 29
15- yellow/black, not listed in spreadsheet (under ECU tab) 10.3V
16- red/ white, not listed 11.8V
17- Pink, right spot, 10.3V Headlight Switch Signal from IJ1 Pin 9
18- Grey, not listed zero volts
19- empty
20- White/red, right spot, didn't test, drivers door lock
21- Black/orange, right spot, no test, drivers seatbelt
22- empty
23- Green/black, right spot, 10.8V, drivers door key

Also pin 11 passenger door lock, black/white, right spot, 9.9V.

This here seems suspicious- IA1, pin 29 is connected to ECU pin 14, white.
IA1 pin 30 to ECU 15, the Y/B not listed under ECU tab.

IA1 pin 29= Headlight Relay Control from Body ECU (B5 Pin 14) to HEAD Relay Pin 1
IA1 pin 30= Dimmer Relay Control from Body ECU (B5 Pin 15) to DIM Relay Pin 2

How is it that ECU pin 14=12.2V, but HEAD pin 1 is 2.7V?
And ECU 15=10.3V, but DIM pin 2 is 9.7V?
Pretty sure the 2.7V is always there when key is on, but the 9.7V only when headlights on high.

Working on IA1 does NOT look fun, I think I can maybe see the W and Y/B wires going into 29 and 30, but can't really touch it.

 

Interesting, this is really puzzling me.

Lets also check the ground at Pin 12 (White/Black) of the Combination Switch.

Ah it seems I missed those when I did the sheet, that sheet was quite an undertaking for me I did my best to proofread it but no surprise I missed a few things. Toyota does not provide pinouts for harness connectors so I created a sheet with them, took me a month or so going over every wiring diagram for the truck. This one only really covers 05-08, I haven't done 09-11 or 12-15 yet.

Pin 15 is DIM Relay Control Signal to Connector IA1 Pin 30
Pin 16 is Flash to Pass Switch Signal from Connector IJ1 Pin 10
Pin 18 is Battery Warning Light Control from Connector DB Pin 1

Were you checking these with the relays in place?

 

Me either.
Where'd the fluffy tailed rat come from?

 

Fixed spreadsheet.

 

Sorry, but- the combination switch is the headlight stalk?
How about the C9 combination meter? I don't really know what it does, but it looks...suspicious.

ECU 14 and 15 checked with relays in.
HEAD relay slots checked with DIM in.
DIM slots are dead without HEAD in.

 

Correct.

That is the dash.
AKA - instrument cluster. AKA - gauges.

 

Yes

The Combination Meter is the Instrument Cluster, all it contains is the indicator LEDs for stuff. It has nothing to do with controlling any of the lighting functions.

With the relay in place and the Body ECU not commanding it on you should see battery voltage at the relay control pins of the Body ECU. I'm still at a loss to why the Body ECU is outputting voltage on those pins when the relay isn't there and why it doesn't seem to be able to properly ground the relays. But you changed the Body ECU and same symptoms?

 

I'm with you here.
That's why I haven't commented.

He did change the ECU according to his recent "Update" to this post.

 

Left window open. It started raining a few hours later, jumped in truck closed window, drove from barn to house with varmint. Got out, closed door with varmint still inside.
Went out in morning, varmint on dash. Banged on hood, varmint could not exit.
Whoops. The interior passenger door panel has a 2 by 8 inch hole at the base of the glass, and half of the back seat is missing foam, also at the base of the glass. I should probably grab a panel for $150, but will probably duct tape some of the chewed up foam back in place.

But, I don't think a squirrel could manage to get at those IA1 wires without removing the parking brake pedal first..

 

Yep.

 

Wow man.
I feel bad for you.

I got a damn skunk I have to "watch for" every time I leave the house at night.
But I don't think I have to worry about it getting into the truck.

 

Ok.

I am going to go back read EVERYTHING.
Start to finish.

It may take me a bit. But maybe we missed something.
Plus, I need to catch up on the last few post.

 

Is this on the DIM or HEAD Relay?
Or do both ground legs of the relay show 2.7v? ( Dim pin 2 / Head pin 1)

 

If I had to choose, I'd pick the door panel damage over getting juiced by a skunk.
Let's be careful out there...

Zip, zilch, nada.
No ground at any switch wires.
Again, power at the ground pin! When connected to (-) battery, White/black = 9.3V, as do pink and red/green.
Green is 9.7, red/white is 10.6.
Yellow and light green show nothing of either.

Mine from left to right/driver passenger when plugged in go pink, green, r/w, yellow, light green, w/black and r/g.

 

HEAD shows 2.7 always, unless key is off. Headlight switch has no effect.
DIM shows 9.7, but only with headlight switch on.