FJ80 CDL Help. *Solved* FULL VIDEO TUTORIAL (1 Viewer)

[Cruisin4Miles]

Like so many before me, my center diff is not locking. I have a 1991 FJ80 with Factory CDL dash Switch.

Ok, so I’ve been trying to figure out what I am missing here. Here is everything I’ve done to try and diagnose the issue. I have gone through the PNWadventures write up, I’ve seen the Toysrus instructions, I have copies of the troubleshooting pages digitally downloaded.

- Jacked up front passenger, wheel in air still spins when 4lo or CDL dash switch engaged.
- did circles on gravel roads in 4lo and/or CDL dash switch engaged, no change
- checked 10amp gauge fuse. Good
-checked 30amp diff fuse. Good
- jumped the CDL indicator switch, CDL light in dash lights up. Still replaced the indicator switch anyways.
- replaced the 4lo indicator switch.
- no cdl dash light when in 4lo or when 4lo indicator harness is jumped.
- continuity test on transmission relay checks out fine.
- 9V test on transmission relay, checks out fine
- relay clicks when shifted into 4lo. No click when CDL button is pressed.
- no noise from actuator when shifted into 4lo or CDL dash button pressed.
- no noise from actuator when 4lo indicator harness is jumped.
-replaced the CDL dash switch, and still no relay click.
- replaced the transmission relay, same results as the original relay.

Now I am here posting for help. I’m pretty sure my actuator isn’t functioning. The only test I haven’t done is apply 9V to the actuator.
My questions are:
What could be the reason my CDL dash switch is not activating the transmission relay?
How do I check that power is being sent from the dash switch to the transmission relay?
Will bad grounds in the actuator cause the CDL dash switch not to function?

Sorry to post a topic that has been well covered, but after reading all these different write ups I’m stumped.

Update:

 

[TheBussman]

apply power directly to the actuator and see what happends, if nothing moves try tapping it while you apply power.

 

[Cruisin4Miles]

apply power directly to the actuator and see what happends, if nothing moves try tapping it while you apply power.

Will do tonight.

 

[TXMeatball]

Same thing on my 97 with pin bypass and CDL button. Replaced all sensors, transmission relay, and even bought a 100 series actuator with the harness adaptor. Pulled my original actuator from the transfer case and bench tested it... it still worked. For whatever reason my actuator just isn't getting power. Assume there's a wiring issue, the plastic protective sheathing for the wires that run above the trans crumbled when touched. Could get the CDL light to turn on when I manually actuated it back and forth.
I gave up but curious what others offer here.

 

[Cruisin4Miles]

Same thing on my 97 with pin bypass and CDL button. Replaced all sensors, transmission relay, and even bought a 100 series actuator with the harness adaptor. Pulled my original actuator from the transfer case and bench tested it... it still worked. For whatever reason my actuator just isn't getting power. Assume there's a wiring issue, the plastic protective sheathing for the wires that run above the trans crumbled when touched. Could get the CDL light to turn on when I manually actuated it back and forth.
I gave up but curious what others offer here.

Did the actuator from the 100 work?

 

[Cruisin4Miles]

To add another question, what are y’all cleaning your connectors/pins with? Are you also spraying the inside of the harnesses?

 

[TXMeatball]

Did the actuator from the 100 work?

Bench testing yes, you have to get a adaptor harness from cruiser outfitters to use one though. Both mine worked. I put my original back in.
It's not hard to get to the actuator when you lower the transmission crossmember. Any M10-1.25 bolt that's a couple inches long helps drop and keeps everything aligned.

To add another question, what are y’all cleaning your connectors/pins with? Are you also spraying the inside of the harnesses?

CRC electronic cleaner. I'll be honest, cleaning pins has never worked for me aside from obvious corrosion like how the window switches get gummed up with carbon.

 

[CharlieS]

Deoxit has worked for me.

 

[Cruisin4Miles]

I was finally off from my 4 day 12hr night shift stretch. So I had time to dive back into figuring out what’s wrong with my CDL. Obviously from my previous post I went down the steps of diagnosing the problem except 1 step…. Applying 9V power to the actuator harness to test if it was running.

Well, as I was re-removing the harness for the 4lo indicator, I must have tugged the harness a certain way, and the harness for the actuator gets disconnected along with it. I’m sure most of you have seen that the 2 wires are secured together. Well that made me wonder… how the hell did the actuator harness disconnect so easily? I reinserted the two harnesses and nothing changed. Still no CDL. Crawled back under and yanked on the harness wires a bit and the actuator harness comes flying off again.

NOW pushing the harness in with every bit of strength my little fingers could muster, I was able to clip the harness all the way into its plug.

And BOOM!!!!

Working CDL. Working Dash indicator. Working CDL dash switch. Working 4lo lock.

The issue was the harness was hanging onto the clip but not enough to easily tell just by looking at it.

SMH. I may be the only d!ckhead to run into this problem.

Question is, how the hell did the harness back off from the connection.

 

[DIRTBIKEUSA]

Question is, how the hell did the harness back off from the connection.

Dirt packed in the connector, vibration. Or something whacked and knocked it loose.

Or you disconnected it and forgot to push it all the way back in last time.

 

[Cruisin4Miles]

Dirt packed in the connector, vibration. Or something whacked and knocked it loose.

Or you disconnected it and forgot to push it all the way back in last time.

I had never touched it previously

 

[Cruisin4Miles]

Uploaded a video demonstrating all the steps I took to diagnose the CDL issue; if anyone needed help.