[terryjmatthew]

Trying to troubleshoot my CDL problem and think I have narrowed it down to the CDL actuator motor. Is this a common problem?

[jonheld]

Your post is a bit vague. What's the problem?

No, the actuators don't fail that often, but I had to replace mine after submerging the vehicle for some time.

Most common failure point would be the finger contacts in the gear assembly. They are the limit switches for the CDL logic circuit.

The actuator assembly can be removed and bench tested.

[terryjmatthew]

The problem is that the CDL will not engage. I have tested the dash switch, the 4wd indicator switch, and disassembled and inspected the Xfer case "ECU"(Relay).
I jumped the harness for the diff actuator motor as described here ( Troubleshooting the Toyota FJ80 Land Cruiser Center Diff Lock (CDL) | Pacific Northwest Backroad Adventures ) and got no response either way.

So that is where we are for now.

A little background info. The current transfer case came from a vehicle that had been parked for several years, but has been in my 80 for several months and has worked fine up until last weekend.

[jonheld]

Then you'll need to pull the unit off the top of the transfer. You can lower the drive train with a floor jack under the transmission cross support. Drop the rear drive shaft. You should only need to drop it 4-6" to get to things, but be careful of radiator hoses. If they're in good shape they'll flex without complaint.

The actuator unit will pull straight up. There is an idler gear that the motor drives to lock the dog clutch in the transfer. You can rotate this by hand to make sure the mechanicals are working properly inside the case.

Seal it all back up with the Toyota orange FIPG goo.

[terryjmatthew]

Replaced the motor with a known good one and still no CDL!
How much movement should the idler gear have? Mine only had about half a turn either direction.

[jonheld]

IIRC, you can lock and unlock the diff with the idler gear pretty easily. You'll need to rotate one of the output shafts a bit to get the dogs to line up.

[jonheld]

Originally Posted by terryjmatthew

Replaced the motor with a known good one and still no CDL!

You did check fuses first right? The 10amp GAUGE fuse and 30 amp DIFF fuse.

I ask because after re-reading your post they were not mentioned.

[terryjmatthew]

I checked them on the trail last weekend. I'm fixing to go check them again!

[terryjmatthew]

Fuses are good.

[jonheld]

Originally Posted by terryjmatthew

disassembled and inspected the Xfer case "ECU"(Relay)

What does "inspected" mean? Did you test this unit under power?

Have you checked pins 2 and 3 on the actuator connector for +12 as mentioned in the article?

Have you checked that pins 9 and 6 on the CDL relay module are getting +12 (9 for lock 6 for unlock). Pin 3 should have constant +12 and pin 2 is ground. Check the diode between 6 and 7. Pin 6 is the cathode.

[terryjmatthew]

I tested the relay as outlined in the previous link. Haven't made it any further than that.