02 tundra no blower no power windows no RPM + other electrical

So I’ve had some electrical issues popping up and I’m going to track progress here so hopefully someone can learn from it…
I don’t know a ton but my family and I own several Toyotas and we’ve often done our own mechanics to an extent.

Windows not rolling down and a/c not blowing at all. Can’t live that way in Florida. Something electrical is going on and I don’t know how to fix it. I had no blinkers, instrument cluster, engine was not accelerating unless gas pedal was pressed all the way to the floor. Found two blown fuses under the hood labeled ETCS and DOME. That brought several things to life but still no windows or a/c blower. No working rpm or speedometer. Probably more things I’m missing. No more blown fuses inside or out, even swapped the large HEATER box fuse with my gf tundra she has the same one. Any idea where to start next? Anyone have a link to learning how to effectively test electrical components? Ready and willing to learn some things. I really need my work truck. Thanks

 

Does the truck have an aftermarket alarm system that is no longer being used. A control box tucked up under the dash somewhere causing issues maybe?

That sounds like an awful lot of fuses to blow at once for seemingly no reason.

 

OP also mentioned Florida.

It wouldn't be unheard of for water intrusion to take out the ECU, or more likely, the main fuse/junction box. Like this guy.

But I like your train of thought with the aftermarket alarm. Sometimes a good idea to check behind the driver kick panel, sometimes the brains end up there.

 

Not sure why water intrusion didn't come to my mind.

OP do you have water getting in your passenger side floor? Or anywhere else on the inside?

 

Yes! You guys are good! This all started when I changed my battery and an alarm kept going off (that I didn’t even know was in there). So went in unplugging stuff to disable it and finally did. Then all the electrical mess started happening. I’ll probably need to pay someone to remove and rewire all that, huh? I like some mechanical work but the wiring is daunting. Do you think I could trade the ecu with my girlfriend’s (exact same truck, year make model) to troubleshoot or does that require programming? Or would that mess something up?
Really appreciate the advice here.

 

@shifty` is the alarm guy. Think he used to install them. You probably have wires spliced into things that don't need to be spliced anymore. Find that brainbox and follow the wires and see what's going on. Up to you on how you want to deal with that.

I do want to ask though, are you certain this is some aftermarket alarm and not a dealer installed RS3000 or similar system. Have a pic of the control box? Have any sort of remote for the truck?

 

this is tangled up under there. I couldn’t find any loose wires and the inline fuse is good. Could this be causing it?

I’m going to dig back into it tomorr night. I’ll update with what happens when I change the ecu. Thanks guys/gals

 

Black box. Dip switches on the side. FCC ID which is required for anything wireless. I'm thinking it's an alarm.

So yes, your problem is probably aftermarket alarm. I would pay a competent shop to uninstall it for you, someone who'll do it right.

I don't see a benefit to swapping ECU. However, if you were to do it, you'll need to confirm the part number is EXACTLY the same on both ECU. The part number should be printed on the unit, in the format of #####-#####, often in the format of #####-0c0##. ECU is tied to truck specs as much as year/model. Not worth risking, make sure the part numbers match.

If you can get me more numbers off the brain box or black box there (could be more daisy-chained off it), I believe this is the owner's/install manual for it, model R23 from Advance Security, Inc: https://fccid.io/H5OR23/User-Manual/8-18105

Never heard of or dealt with that alarm manufacturer. But that said, I reckon if you plug the alarm back in, some of this weird shit will potentially go away.

Alarms often die in the 10-20 year range. It's inevitable.

 

Aftermarket alarms are shit. Period dot end of statement.

 

Agree 1,000%. I understand the desire for some of the features, like 2 way comms and remote start, but it's a problem waiting to happen.

We sold them because people wanted them. If people asked, we'd give them an honest answer and tell them to expect to replace in 10-15 years regardless which brand.

Most people didn't care and bought one anyway.

It's the 1st thing I rip out of a used car if I find installed.