So I searched around a bit but I couldn't find anybody talking about this specific speed of flashing.

Usually when the lock is trying to engage the light flashes somewhat quickly. I had taken apart my dash today to swap out the cluster lens and to get a little dead bug out of there finally... Bastard... Anyway. I also took the time to swap the diff lock button with the little Toyota security thingy.

I figured this would not hurt anything..

Well so now after I gotten everything buttoned back up the above mentioned issue is now happening. I can confirm that pressing the button does not cause the little motor to engage at all where is it did before. before when I press the button I could hear it try to actuate, and then as soon as it could it would lock.

Currently when I press the switch there's absolutely nothing happening...

I confirmed that it is plugged in firmly, can't really figure anything else out...

2000 4Runner SR5 Auto v6 4x4

Flashing example:

Normal: flash flash flash flash

Issue: .......Flash........flash..........flash.........f lash........

When you swapped the button with the “little toyota security thingy” did you swap harness plugs too or just position in the dash?
If it’s flashing slower and not activating the motor than it might not be getting enough power.
Maybe 5v instead of 12v?
Idk this is the only thing I can think of.

I've got everything taken apart again. I'm definitely pretty sure there's only one plug that can fit. I checked to make sure that the wires hadn't pulled out of the plug but they seem okay I think.

I unplugged and replugged and tried it again and it's the same result
Damn

Correct me if I'm wrong, but there was no rear diff-lock available after 1999. Is this the center diff you're talking about?

Nah she has the rear locker. I think it's 2001 and 2002 that do not have it.

I've messed around a little more and still have had no luck

Perhaps you're not remembering it correctly, the quick RRDIFF LOCK flash either means your moving to fast to engage RRDIFF LOCK, or the vehicle thinks you are, or you're not in 4Lo or grey wired. Either way it should be a slow flash and it should atleast click at the locker to make an attempt if all is well back there and at switch and everything mentioned earlier is satisfied, sounds like something isn't happy with the switch, did you losen up your grey wire ground by mistake or damage the connection. It's only 2 wires on the RRDIFF Lock button unless you added the illumination like the Tacos got, I stuffed an LED in mine.

Well usually she will flash but I will hear the motor or whatever try to move the lock. Right now she does nothing at all, in any gear or mode. I do have the grey wire mod. I checked all the connections and at least at a glance they seem okay.

Seems like the motor isn't getting the signal. Is there a relay or fuse?

Should be a relay and a fuse if I’m not mistaken
The actual switch could have gone bad also so it’s not sending the signal to the motor
Best thing to do is check fuses and if that’s all good bust out the multimeter and make sure you have good ground and power at least at the switch to start with.

Just weird that the truck is detecting the switch press since it flashes slowly.

I was thinking about pulling the actuator off and bench testing it. But the fuse and relay sound good first... Any idea where they are located?

Not sure. @mtbtim might

Oh mighty timmy, can you offer your wisdom?

I have a 1997 4runner with the rear diff locker. MIne also flashes when I activate it. HOwever, mine does lock. I thought the flashing was normal?