chicago60647

I recently bought a '98 4runner with 311,000 miles on it. It runs great but has some electrical issues.

The rear wiper, window, and defroster don't work (altho the defroster light turns on). I've read up on the issue and have tried jiggling the wiper. I also confirmed the window works by connecting it directly to the battery. My key doesn't turn the rear hatch lock so I can't tell if the window operations works by key.

I have almost no experience with electronics. The most I've done is solder a headphone cable back to together.

I tore off the panel to see what I could find and I see there is an empty blue box labeled Control Unit. The box is empty, I'm assuming this is not good? Or is it's only function to hold some of the wires? None of them seem to fit snugly in there.

Here is a picture of the box and the nearby wires


As you can see, there is nothing in the blue box and none of the stray plugs seem like they'd fit in there.

I found this picture on the forum, but I can't really make out what's up.




Sorry if this is a stupid question, I'm just learning! Thanks for the help!

chicago60647

On closer inspection, it looks like the white plug should plug into the blue box, but the blue box is missing the plug? Since that's missing and my key doesn't turn in the tailgate lock, perhaps this isn't the original hatch?

wyoming9

iTrader: (1)

That Blue Plug is a Junction connector

Nothing gets plugged into it Toyota`s way of splicing wires

It has a cover to prevent shorts and dirt getting in there.

Have you checked the fuses the 30 amp power fuse and the 20 amp wiper fuse

the 10 amp gauge fuse the 15amp defogger fuse .

All the window and wiper functions go through the window relay which in a 98 is inside the hatch (tailgate)

Trouble shooting is one step at a time starting with the power source

chicago60647

Thanks for the help and the reply

So the blue box serves no other purpose than to just protect the wires?

I guess it's time to start checking fuses, thanks again

wyoming9

iTrader: (1)

Think of the blue connector as just a box where wires are joined .

Pop the hatch lock cylinder out get it re keyed to match your ignition and door keys.

It is possible the window lock is engaged could be any of the safety switches not working.

311,000 miles quite possible to have broken wires going into the hatch switches just worn out

If your going to do this type of work time to get a Multi meter

Learn the concept of simple DC circuits

Lots of help here we will help you get it figured out

chicago60647

It turns out the blue box houses the rear ECU. The PO of my car must of tipped out the ECU but left the blue plastic housing for it. Bought a new ECU, plugged the white plug into it, and everything worked!

wyoming9

iTrader: (1)

I see what happened you were looking at one thing and me another one.

That is why it didn`t make sense to me glad you have it figured out and things work