SOLVED: CDL won't activate

[lumbee1]

After a trip to Windrock in June, I noticed my rear locker wasn't working as expected. The light would blink like it was try to engage and it felt like the locker was engaged. I thought it might have just been the transfer indicator switch. The CDL and front locker performed fine the entire trip and has for years.

Yesterday I removed the transfer indicator switch from the rear axle. Electrical connections looked great. Switch tested fine. I cleaned with contact cleaner and added a dab of dielectric grease. I went to check to see if there was any difference in performance. I started the truck and engaged the CDL dash switch. No CDL light came on and no click from the relay. I moved the vehicle back and forth, drove around the cul-de-sac. Nothing.

I'm not sure what I could have done to make the CDL stop working. I checked the 10A and 30A fuses. Both looked fine and tested fine. I'm getting 12V at both fuses. I disassembled the CDL relay and followed the FSM. It tested perfectly with a 9V battery. I checked the front and center transfer indicator switches as well. They didn't test as cleanly but electrical contacts were super clean. I used a paper clip jumpered all three transfer indicator switches on the transfer case. Nothing from the relay.

Searching mud I found a statement:
The ground for the ECT relays actually run through the actuator assembly, this is how the assembly limit switch works. It tells the relay box to shut off by breaking ground to the relays as the limit switch reaches the end of travel.

^ Basically, even if the ECT box doesn't emit any relay clicking, it can still be 100% fault of the actuator.

Post in thread 'CDL Actuator Fun'

Nov 19, 2012

After I did all of the above, wouldn't it be a safe bet to pull the actuator? Should I even touch the tranny relay? Would it click if it was shot?

I would pull the actuator and check inside for water/corrosion. When putting into 4-low (or hitting the CDL button) the ECT (trans relay) in the driver's kick panel should go "click" then whirrr of the actuator, then "click" a second time to stop the actuator motor.

The ground for the ECT relays actually run through the actuator assembly, this is how the assembly limit switch works. It tells the relay box to shut off by breaking...

• asutherland

I proceeded to remove the actuator motor from the transfer case. The gear and drive looked great. Definitely no water intrusion on that side. I removed the P3 bolts on the contact side of the actuator. The top would not budge. I wedged a screwdriver in the case tapped it a few times and broke a chunk of the top of the motor actuator. Now I'm major sad and need help.

Triage for CDL:
Both 10A and 30A fuses test good.
CDL switch tests good with hazards.
Hazard switch used as CDL switch.
CDL relay tests good according to FSM
Tested CDL relay with 9V battery and clicks.
All transfer indicator switches test good enough.
Motor actuator looks good on gear side.
I have not opened top of motor actuator due to damage.

No light from CDL, no noises from CDL relay, no motor noises from CDL actuator.

I've been following these links for help.

Thread 'CDL Actuator Fun'

Nov 18, 2005

On the last trail run the CDL would not lock, after some trail side investigation it was determined that the best action was to jumper the CDL indicator switch so the axle lockers would work and complete the day.

After living in denial for a couple of weeks I tore into it, the transmission relay (where the pin 7 mod is done) failed the FSM test, opened it up and there was a burned trace on the board. Two of the relays were desoldered and removed, they tested good, the burned trace bridged and the relays soldered back on. It now passed the test and works good. With the circuit testing good...

• Tools R Us
• Replies: 135
• Forum: 80-Series Tech

Troubleshooting the Toyota FJ80 Land Cruiser Center Diff Lock (CDL)

www.pnwadventures.com

What am I missing?

 

[baldilocks]

Your indicator switches work “well enough”? And you have not seen inside the actuator. Seems these are the only components that have not tested as they should or at all in the case of the actuator.

Can you simply apply 12v directly to the actuator to see if it works?

Have you used a meter to ring out the wires checking for continuity?

I’ve never had OEM lockers so I have no specific experience to offer.

 

[jonheld]

You can run the CDL motor with a 9V battery. Pins 2 and 3 on the connector.

 

[1FZj80]

I proceeded to remove the actuator motor from the transfer case. The gear and drive looked great. Definitely no water intrusion on that side. I removed the P3 bolts on the contact side of the actuator. The top would not budge. I wedged a screwdriver in the case tapped it a few times and broke a chunk of the top of the motor actuator. Now I'm major sad and need help.

Did you clean and verify continuity between the internal sliding contacts and the gear?
When mine stopped working the issue was the contacts that slide on the gear inside the actuator and a film of grime on the gear itself. Everything tested ok per the FSM but did not work until I cleaned these contacts and the gear.

 

[lumbee1]

Did you clean and verify continuity between the internal sliding contacts and the gear?
When mine stopped working the issue was the contacts that slide on the gear inside the actuator and a film of grime on the gear itself. Everything tested ok per the FSM but did not work until I cleaned these contacts and the gear.

View attachment 4210645

After breaking part of the top off the contact plate, I just walked away. Your post inspired me to look at it again.

I was able to get the top plate off and here's where it gets interesting.
The last contact was covered in a thick, sticky, black goo. I wiped off most of it in the picture but you can see it pooling at the bottom.

When I removed the top, the black goo was quite stringy like moly grease.
In addition, the contact surface was a combination of grease and a baked on thick sticky brown material. I was able to scratch it off with my fingernail. There was some fresh grease still left on the surface so I moved it around. Most of the grease in here felt cakey.

On top of that, the reason the the top wouldn't come off was because it was semi-welded on with what appears as aluminum oxidation. I was able to scrap this off with a screwdriver. I was concerned about heavy pitting underneath but there was none. I'm very confused by what this could have been.

Either way, it appears that the dirty contacts were the root cause of my troubles. In the top photo, you can see that one of the three mounting ears is missing. I plan on adding MolyKote YM102 to the gear and screw and along the perimeter to give this the best chance of being water tight again.

 

[lumbee1]

Since the indicator is blinking and there’s no relay or actuator noise, I’d split the diagnosis at the actuator connector: verify power/ground during a CDL command, then briefly run the motor directly from a 9V battery across pins 2 and 3 as Jon described. If the motor runs, inspect/clean the internal contact track and gear for dried grease or contamination—the position contacts can stop the system even when the motor is fine. If it won’t run directly, the actuator/motor is the likely fault. Hope that narrows down whether you’re chasing the switch, wiring/relay, or the actuator itself.

No indicator at all. The CDL relay is dead silent but bench tested fine.

See post above but contacts were dirty and it may have just been coincidence that my CDL stopped at the same time my rear locker indicator started acting up.

 

[1FZj80]

No indicator at all. The CDL relay is dead silent but bench tested fine.

See post above but contacts were dirty and it may have just been coincidence that my CDL stopped at the same time my rear locker indicator started acting up.

Your rear locker will not engage until the CDL is locked.

 

[lumbee1]

Your rear locker will not engage until the CDL is locked.

Yes I am fully aware. Originally, the rear locker seemed to be engaging but the locker indicator would blink. After verifying the rear locker transfer indicator switch for continuity, the CDL wouldn't come on for me to test the rear locker. That started me down this path.

 

[lumbee1]

You can run the CDL motor with a 9V battery. Pins 2 and 3 on the connector.

View attachment 4210465

I did this. Motor works in one direction but flipping the leads doesn't make it go in the other direction. I am hearing a click inside the electric motor. I have not opened the electric motor to look at brushes or the commutator.

 

[lumbee1]

Your indicator switches work “well enough”? And you have not seen inside the actuator. Seems these are the only components that have not tested as they should or at all in the case of the actuator.

Can you simply apply 12v directly to the actuator to see if it works?

Have you used a meter to ring out the wires checking for continuity?

I’ve never had OEM lockers so I have no specific experience to offer.

Transfer indicator switches have very low resistance but not zero.

 

[lumbee1]

CDL motor actuator is working again. I connected it up to the harness and tested. While I didn't have anyone to see the gear turning, I could hear the motor move back and forth.

 

[baldilocks]

Did you resolve a system fault or did it mysteriously start working again?

 

[1FZj80]

CDL motor actuator is working again. I connected it up to the harness and tested. While I didn't have anyone to see the gear turning, I could hear the motor move back and forth.

Is the rear also working now?

 

[lumbee1]

The motor case was rusty so I pulled it off, wire-wheeled it, and put a coat of flat black enamel on it. I'm waiting for that to dry at the moment.

I just picked up some ultra black to reseal it to the TC when it's all back together.

 

[lumbee1]

Did you resolve a system fault or did it mysteriously start working again?

After cleaning the contacts and reassembling, it's working great.

 

[lumbee1]

Is the rear also working now?

I will find out tomorrow when it's all back together.

 

[lumbee1]

Thread title updated. CDL operates perfectly now.

Unfortunately, my rear locker acts the same. The locker engages but the locker indicator just blinks. I'm going to pull the transfer switch and see if manually activating the switch in my hand does the same. This switch bench tested fine.