Identify transmission and CDL actuator motor missing? (1 Viewer)

Joined
Sep 19, 2022
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8
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Naivasha, Kenya
Hello folks,

I recently bought a HDJ81 with a manual transmission. According to the model number it used to be an automatic.
Now I got the following questions/problems that I couldnt answer even after googling and searching the forum for a while.
The car has all diff locks, and a CDL switch installed. As far as I can tell the CDL is permanently locked (in all drive modes I get binding when steering hard).
Both the front and rear can be engaged from the switch and will also lock (through test driving).
The CDL light in the dash used to be off, I found the sensor was not connected and I will replace it this week (the wiring works as I have shorted the sensor connector and the dash light lights up). The front and rear lock lights do blink when engaged and keep blinking when locked.
When changing the sensor I noticed there is no actuator motor for the center diff (at least not where I would have expected it after my research). Also from my research I believe that the transmission is an H151 (?!).
I found another picture on the forum that shows the same transmission without the actuator motor and I was wondering how is the CDL engaged?
Here is a picture of the transmission (which was out of the car for a leak) and from spot where I would have expected the actuator motor.
My guess and fear is now that when the transmission was changed to manual, it wasnt done right and now the CDL is permanently locked without any possibility to unlock it.

I hope someone can shed some light on this.

CD.jpg
model.jpg
Trans.jpg
 
Joined
Mar 15, 2021
Messages
400
Location
Orangevale (aka, Sacramento)
Hello folks,

I recently bought a HDJ81 with a manual transmission. According to the model number it used to be an automatic.
Now I got the following questions/problems that I couldnt answer even after googling and searching the forum for a while.
The car has all diff locks, and a CDL switch installed. As far as I can tell the CDL is permanently locked (in all drive modes I get binding when steering hard).
Both the front and rear can be engaged from the switch and will also lock (through test driving).
The CDL light in the dash used to be off, I found the sensor was not connected and I will replace it this week (the wiring works as I have shorted the sensor connector and the dash light lights up). The front and rear lock lights do blink when engaged and keep blinking when locked.
When changing the sensor I noticed there is no actuator motor for the center diff (at least not where I would have expected it after my research). Also from my research I believe that the transmission is an H151 (?!).
I found another picture on the forum that shows the same transmission without the actuator motor and I was wondering how is the CDL engaged?
Here is a picture of the transmission (which was out of the car for a leak) and from spot where I would have expected the actuator motor.
My guess and fear is now that when the transmission was changed to manual, it wasnt done right and now the CDL is permanently locked without any possibility to unlock it.

I hope someone can shed some light on this.

View attachment 3119177View attachment 3119178View attachment 3119179
No expert on any of this. On my vehicle the center differential locker isn't part of the transmission (automatic, standard in USA). It is part of the center differential, aka, transfer case.
Also, blinking indicators signifies that the locker is not engaged, yet.
If you're sure that the driveline is binding, you are getting "windup" which features: significant stress leading to potential massive damage, and as a bonus is unsafe.
Best of luck in finding a remedy
 

Squash

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Lockers will still engage even if blinking. Blinking may indicate a broken wire, bad sensor or a second washer thus limiting the sensor's ability.
 
Joined
Sep 19, 2022
Messages
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Location
Naivasha, Kenya
No expert on any of this. On my vehicle the center differential locker isn't part of the transmission (automatic, standard in USA). It is part of the center differential, aka, transfer case.
Also, blinking indicators signifies that the locker is not engaged, yet.
If you're sure that the driveline is binding, you are getting "windup" which features: significant stress leading to potential massive damage, and as a bonus is unsafe.
Best of luck in finding a remedy
You are right, the actuator motor should be on the transfer case, I wrote transmission by mistake. The close-up picture is actually of the top of the transfer case where the motor is usually located.
By binding I meant that I can tell whether the diffs are locked or not. Of course I dont drive any tight corners when the steering is locked up...

Lockers will still engage even if blinking. Blinking may indicate a broken wire, bad sensor or a second washer thus limiting the sensor's ability.
Yes, I know for a fact that the diff locks are engaging. Thanks for the tip about the wiring, I will check that out.
 
Joined
Dec 12, 2021
Messages
18
Location
Blue Mountains, Sydney
That's a HF1A transfer case by the looks of it, factory part time. Photo of my HF1A below to compare. Does your low range shifter have H - N - L on it? HF1A needs to be shifted forwards (towards dash) one more time to disengage 4WD (pretty much locked centre). Sounds like it's been converted from a full time case when the H151 went in and it's currently sitting in H4, not H2. Models with this transfer case didn't have a CDL light in the cluster, but a "4WD" light.

Gonna make a guess that the lockers won't engage fully unless the locker ecu thinks the CDL is engaged, hence blinking lights.

Part time goes:

H2
H4
N
L4

Try pushing the lever forward a bit more, there are definitely 4 distinct positions you will feel.

20220921_195745.jpg
 
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Joined
Sep 19, 2022
Messages
8
Location
Naivasha, Kenya
That's a HF1A transfer case by the looks of it, factory part time. Photo of my HF1A below to compare. Does your low range shifter have H - N - L on it? HF1A needs to be shifted forwards (towards dash) one more time to disengage 4WD (pretty much locked centre). Sounds like it's been converted from a full time case when the H151 went in and it's currently sitting in H4, not H2. Models with this transfer case didn't have a CDL light in the cluster, but a "4WD" light.

Part time goes:

H2
H4
N
L4

Try pushing the lever forward a bit more, there are definitely 4 distinct positions you will feel.

Yeah, that looks exactly like it!
I have the part time shifter (H2-H4-N-L4) but the dash has a CDL light instead of a "4WD". I guess it means they didnt change the dashboard.
So the centre will always be locked in either H4 or L4?
I will try again today, and if so, that will already answer all my questions. Because I thought it would only lock in L4 (that's probably the case then for a different transfer case?)
And that would also mean that the CDL switch on the dash is obsolete...

20220914_163224.jpg
 
Joined
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Messages
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Blue Mountains, Sydney
Yep, that's a full time dash. CDL switch may not be obsolete if the diff lock ecu needs a CDL signal to allow the lockers to engage, I have a feeling they do.

Center is always "locked" in H4 & L4. Part time case should really have locking/unlocking hubs up front, does yours have them?
 
Joined
Sep 19, 2022
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Naivasha, Kenya
Yeah, I have manual hubs on the front.
So the switch doesnt have any function for me, right?
To make the conversion complete I would need a different ECU and dashboard? That might also explain why the front/rear locker dash lights only keep blinking even when engaged...
 
Joined
Dec 12, 2021
Messages
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Location
Blue Mountains, Sydney

Switch may still have function for you. Looks like the CDL switch needs to be activated for the lockers to work. If the lockers are blinking, this could be why. Try pressing the CDL button before locking the diffs and see if the lights stop blinking. Could also be the sensors.

Nope, don't need a different ECU. There is a separate ECU just for the diff locks. No need for a different dash either. I'd have to go through the wiring but when you engage H4 it should illuminate the CDL light. As long as there's a light to remind you to disengage it on the road, no worries.
 

mudgudgeon

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The locker ECU is activated when the CDL is switched on, or when you shift to low range.

Front and rear lockers can't be activated until you either shift to Low range, or hit the CDL. Then you need to rotate the locker switch. Once the ECU has power, the front and rear lockers are independent of the CDL

If the lights for the front and rear lockers are blinking, maybe their actuators aren't functioning?

The lockers can be slow to engage. You can test them by turning them on, and slowly driving in a figure eight to see if they engage as axles rotate at different speeds
 
Joined
Sep 19, 2022
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Naivasha, Kenya
I did some more testing which didnt have any results at first.
I checked the CDL (or in this case 4WD) sensor again and one of the cables came lose (I have a provisionary connection).
After fixing that now the CDL (4WD) light comes on when switching to either H4 or L4.
Front diff is now engaging and the light stops blinking.

Rear diff doesnt engage (no click from the ECU) and light still blinking.
I still have a lot of steering resistance and clicking noises from the front wheels when hubs are locked and in H2 (no 4WD or diff lights on in dash).
But I will do some research on these issues as they are separate from this topic I feel, which has been answered.

Thanks guys for your help!
 
Joined
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Messages
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Blue Mountains, Sydney
Have you checked the connection for the locker at the diff itself? These diagrams should be everything you need.

How does the car drive/steer with the hubs unlocked in H2? Keeping the hubs locked shouldn't affect the steering, but let's just try everything and narrow it down. Could be an issue elsewhere, perhaps the steering box, who knows. I've discovered many problems/solutions while trying to fix other stuff.

Glad you've sorted some of the issues.


diff 2.jpg
DIFF EWD.jpg
DIFF ECU 3.jpg
 
Joined
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Mister Gerry, thanks for the diagrams, I will check the connections in the course of the next few days.
In 4WD when turning the locker switch to rear, the dash light starts blinking but there is no sound/clicking from the ECU (I assume thats what should be clicking) and no sound from the actuator motor. When turning the switch further to front, the dash light comes on, there is a noticable click from the ECU and noise from the FDL actuator motor and the front diff locks (I can tell from the steering).

Coming to the hubs, while in H2 and hubs unlocked, steering is normal, no resistance and I can do full turns of the steering wheel. Also no sounds/noises from the front wheels.
When I lock the hubs and still in H2 (no 4WD light in dash) there is noticeable steering resistance (less than when diff is locked), I cant do all turns of the steering wheel. Also there is a knocking/clicking sound from the front wheel when steering hard and moving.

Addition:
I forgot to mention that the CDL switch makes no difference when operating the locker switch.
 
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Joined
Dec 12, 2021
Messages
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Location
Blue Mountains, Sydney
Sounds like something is up inside your front diff. Jack the front axle up and lock the hubs, spin one wheel and watch to see if/how the other rotates, report back.

Could try removing the front prop shaft and drive around with the hubs locked. If it's still hard to steer, front diff is definitely the problem. When was the last time you changed the diff oil and serviced the axles, knuckles etc.?
 
Joined
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I jacked up the front axle today and when hubs are locked both wheels spin in H2, no CDL or front diff lock engaged.
Seems like I have to take it to the shop to have it checked.
The car was there just some weeks ago to check everything. In the front they just changed steering and tie rod ends and almost all the bushes, but nothing on the diff or axle.

Regarding the rear diff lock, the actuator motor is connected but I havent checked anything further. Next step I want to find the ECU and then check all the cabling with a multimeter. Or I'll start removing and opening up the actuator to see how it looks.

It'll have to wait until late next week as I'll be driving in the Maasai Mara for a couple of days :)
 
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