How To Trouble Shoot 4x4 Actuator

Front ADD actuator is also beeping when plugged in and switched to 4HI.

 

@PyriteNH12 have you removed and inspected inside the transfer case actuator?

 

I haven't done this, was hoping to rule out the transfer case actuator since it responds and engages the front drive shaft. I have performed a resistance check on both detection switches on the transfer case near the transfer case actuator and they check OK.

 

when you opened up the front actuator for inspection, aside from soldering and cleaning.... did you also bend the three prongs slightly to ensure contact??
here is a picture stolen from @jberry813 as well as a link to his thread explaining the steps he took.
https://www.tacomaworld.com/threads...-moderator-with-a-tacoma-build.455075/page-42

 

@uurx Yep checked that. I actually popped the cover off again to double check and those three drag prongs are contacting fine. They are making a perfect trail through the new grease.

I'm going to rig of a relay test circuit later today. Per TSM, they want you to "create a circuit" using a fuel pump relay to test the ADD then perform resistance check. This will be my last step before ordering an actuator.

 

g/l keep us posted

 

Thanks men , a lot if helpful info here

 

Could use some help guys. Truck started giving me issues in the cold weather last winter with not wanting to fully shift between 2wd/4wd/4lo. Went away in the summer so I forgot about it. Now its cold and not working again. Original main issue was it would shift into 4wd and back into 2wd but 4wd light would continue to flash. I took apart the front add actuator, soldered and bench tested the parts to confirm function. Reinstalled and problem persists. Removed transfer case actuator and cleaned up the inside of that + bench tested motor. Now here is my current issue- I push the shaft on the t-case all the way forward (2wd), set trans actuator to what I believe is the correct timing for this phase. Switch inside truck is on 2wd. When I turn key on, the trans actuator turns the wrong way and puts the truck in 4wd (steady light in dash) and 4lo light blinking on the dash. Before I turn the key, I confirmed that the truck is in fact in 2wd. Im at a loss of what to do next. Please help.

 

this really needs to be a sticky!

 

Bump with problem still persisting.
My current plan is to have the actuator off the transfer case yet fully assembled. From there I'll be able to reach into the actuator and apply pressure to the two sensors that tell the 4wd ecm where the transfer case is currently keyed. If these sensors aren't satisfying the 4x4 ecm, I don't believe power can/will be sent to the actuator. Only two sensors with two locations for each sensor (in and out). I'll try all variables to see if I have the transfer case a few teeth off on the selector rod or if it's those sensors that have shit the bed. Those sensors "rarely go bad" but then again, rarely do people drive fully flooded vehicles. Up coming weekends project

 

Next bump. I now know that I have the front ADD keyed correctly and in the right place (all the way passenger for 2wd). The trans actuator is key correctly as well. The small gear is sitting on the 3rd tooth of the shifting rod which is also correct for 2wd. Front drive shaft spins freely. The switch inside the cab is in the 2wd position matching all other variables. When key is turned- nothing happens at either actuator now. 4x4 and 4lo lights continue to blink. Anyone care to make a suggestion or know how to manually reset the 4x4 ecm memory. I'm all ears

 

@Lux - for 2nd gen actuator, but some stuff might apply to your 1st gen.

 

Bump, was able to get the lights off on the dash by keying everything to 4lo then slowly working everything into 2wd again with the key going on and off multiple times. The sensors on the transfer case actuator are Toyota part number 84222-12010 and 84222-35121. The 12010 sensor has alternate part numbers but the 35121 doesn't seem to have any other manufacturer than Toyota. 12010 alternate part numbers are-- Napa ns6421,

$32 Acdelco e2209a (88923311) Back-Up Lamp Switch

Acdelco e2209a, Echlin 8950,

$19 Beck/Arnley 201-1788 Back-Up Switch

Beck/Arnley 201-1788, Standard Motor Products ls228, and Airtex/Wells 1s5826.

After I got everything into 2wd, I had my dad hit 4wd while I watched the trans actuator fail to turn the small gear (small cover with 3, 8mm screws was off) it didn't have the power to pull the shift rod outta the transfer housing telling me the motor on it is shot even after a rebuild so I'm forced to purchase a new one. When the new one is on, I'll update here.

 

OMG........

bump to top

 

FJ transfer case and manual hubs ftw

 

That is one of the best options but certainly not the easiest or cheap. With that said, looks like you did a nice job doing it on your build.

 

nice build........I see the X/fer case.........

 

rock solid toys can set you up with a quote.

 

After discovering that my 4x4 wasn't working ('07 manual 4 banger), I've been trying to diagnose the issue. In my case, like many others, it was the ADD actuator. However, it wasn't the contacts. The small DC motor inside the actuator wasn't turning. The inside of my actuator was clean, so I can only assume that my lack of "exercising" the 4x4 system, including this motor, caused the issue. Anyhow, it was easy enough to get it free - I connected a 9 volt battery to the motor. The motor didn't want to spin at first, but seems to work just fine now. And now the actuator drives the sleeve in the front differential.

The only reason I mention this is that I read everywhere that the contacts inside the actuator might be the culprit. I only thought to check the motor after discovering my contacts were fine.

 

playing with mine....the Tacoma.................

goes in/out of 4H......but seems the 4L in/out is the issue......

have to turn key....restart...you know.......before it will go back to 2H.......

W T F Toyota.........