KZJ78 95 Flashing Hub lock light (1 Viewer)

[Lomoski]

Hey everyone,
I'm new to the forum and have a new to me 1995 KZJ78. I have been searching the forums and haven't found an answer to this question.

Whenever I turn on my truck. The hub light starts flashing. If i press the hub lock button it goes solid and then I turn it off and the light stays off. I have replaced the carbons on the left side, one of them was broken. When I turn it on I can hear both hubs "whirring" but then the light starts flashing. When I jack it up and lock the hubs both sides lock (it has limited slip diffs) and the wheels spin in opposite directions. Not sure what else to do. Any suggestions?

Thank you.

 

[Kapfupi]

When you reassembled after replacing the carbon did you use a pin to hold back the brushes from the contactor rings. If you don't the brushes get caught up and bent. Maybe there could be a weird short of some kind as a consequence.

 

[Lomoski]

When you reassembled after replacing the carbon did you use a pin to hold back the brushes from the contactor rings. If you don't the brushes get caught up and bent. Maybe there could be a weird short of some kind as a consequence.

Hi kapfupi, I did indeed insert a wire into the hole and retained the carbon brushes. It was flashing intermittently before and is still doing it. I think I'll just get the avm manual lockers as they seem a lot more reliable. Cheers mate and happy new years.

 

[oldblue]

Correct me if i'm wrong, If you have a Diff Lock then both wheels will rotate the same direction.

 

[Lomoski]

Correct me if i'm wrong, If you have a Diff Lock then both wheels will rotate the same direction.

That would be correct for a locking diff, mine is a limited slip though. Do you still turn electric hubs into manual? Cheers!

 

[oldblue]

Sorry i meant limited, If a limited slip diff is working ok then both wheels turn the same direction, Yes still converting hubs but it has slowed down due to there age.

 

[Lomoski]

Sorry i meant limited, If a limited slip diff is working ok then both wheels turn the same direction, Yes still converting hubs but it has slowed down due to there age.

You are correct, my truck does not have limited slip or locking differential. What do you charge for conversion and where are you located? Cheers!

 

[oldblue]

Located in New Zealand, I have done a couple of conversion for guys in other country's but the freight cost etc makes it to expensive. NZD$160.00 +Freight. I would need your end caps and you would have to do the striping down of the hubs.

 

[graysworld]

I have a similar problem and wonder if anyone has a solution for me. 1995 KZJ78 SX Auto gearbox (Japanese model). My 4wd light is flashing and the hub lock light is not working at all. I have only just bought the truck and so far Most things are working! So with the truck up off the ground the hubs appear to be locked. engaging 4wd drive and the front wheels turn. I have been told that because the electric hubs are unreliable someone could have somehow permanantly locked them. This has possibly confused the ECU and that is why the hub lock light stays off and the 4wd light flashes. Can anyone confirm this and indeed does anyone no of a fix to get the 4wd light to stay on? I guess I need to strip the hubs to see what is going on. I will do this is due course as I want to change all the seals and bearings and discs (rotors) and pads. Any help appreciated.

Regards Graeme

 

[GreatScot]

I have a similar problem and wonder if anyone has a solution for me. 1995 KZJ78 SX Auto gearbox (Japanese model). My 4wd light is flashing and the hub lock light is not working at all. I have only just bought the truck and so far Most things are working! So with the truck up off the ground the hubs appear to be locked. engaging 4wd drive and the front wheels turn. I have been told that because the electric hubs are unreliable someone could have somehow permanantly locked them. This has possibly confused the ECU and that is why the hub lock light stays off and the 4wd light flashes. Can anyone confirm this and indeed does anyone no of a fix to get the 4wd light to stay on? I guess I need to strip the hubs to see what is going on. I will do this is due course as I want to change all the seals and bearings and discs (rotors) and pads. Any help appreciated.

Regards Graeme

Did you ever get this sorted out?

Also do you know where the relays and electric locking hub ECU are located?

I have the same year and model, but manual.

 

[graysworld]

I replaced the electric hubs with manual ones. Much more reliable.

 

[oldblue]

The ECU is located behind the dash just up from the steering column right side. square box approx. 5" x 5"
I have been converting electric hubs since 2004 and still can't find an answer.

 

[GreatScot]

I replaced the electric hubs with manual ones. Much more reliable.

Thank you. going to try a fix first and then convert to manual once I can gather the parts.

The electric ones worked well for a long time (30,000kms of my ownership) so I'll see what more i can get out of them

 

[GreatScot]

The ECU is located behind the dash just up from the steering column right side. square box approx. 5" x 5"
I have been converting electric hubs since 2004 and still can't find an answer.

Thanks Kevin - I found it by pushing the button with just the electrics on and listening out for the relay clicking. found it easy enough.

if i manage to repair the brushes and still having problems, i will have a look inside the ECU and see if it might be capacitors leaking on the circuit board....a bit like the Engine Control ECU

 

[GreatScot]

Hey, so I installed manual hubs. The hub light is flashing so I pulled the plug from the ecu - no flashing now - but I can't engage the transfer box.

I have the car up on stands, lock the hubs, see the front drive shaft turn when I spin the wheel with the hub lock engaged.

If the transfer box were engaged, I wouldn't be able to spin the wheel, right? What am I doing wrong?

 

[kgrove]

Hey, so I installed manual hubs. The hub light is flashing so I pulled the plug from the ecu - no flashing now - but I can't engage the transfer box.

I have the car up on stands, lock the hubs, see the front drive shaft turn when I spin the wheel with the hub lock engaged.

If the transfer box were engaged, I wouldn't be able to spin the wheel, right? What am I doing wrong?

Did you ever get a good diagnosis on yours?

I have what sounds like a similar problem on my '95 KZJ78. I was going to do it myself but it sat for months waiting for me to have the time, so I finally took it to a mechanic to rebuild the knuckles. When I got it back, the hub lock indicator light flashes intermittently - lights for maybe 1/2 second, then goes dark for maybe 1-2 seconds, and repeats. Neither the hub lock or H4 button appear to do anything, though when I engage the H4 button, the H4 indicator joins the hub lock indicator in flashing at me. I haven't tested whether the front hubs are engaged or free spinning.

My suspicion is the mechanics bent or broke the brushes. If that were the case, what would be the symptoms and how would I confirm that's the problem? Anyone have the part numbers I'd need to replace those brushes? The more expensive solution would be to convert to manual hubs, but I'd like to avoid that if possible.

 

[GreatScot]

Did you ever get a good diagnosis on yours?

I have what sounds like a similar problem on my '95 KZJ78. I was going to do it myself but it sat for months waiting for me to have the time, so I finally took it to a mechanic to rebuild the knuckles. When I got it back, the hub lock indicator light flashes intermittently - lights for maybe 1/2 second, then goes dark for maybe 1-2 seconds, and repeats. Neither the hub lock or H4 button appear to do anything, though when I engage the H4 button, the H4 indicator joins the hub lock indicator in flashing at me. I haven't tested whether the front hubs are engaged or free spinning.

My suspicion is the mechanics bent or broke the brushes. If that were the case, what would be the symptoms and how would I confirm that's the problem? Anyone have the part numbers I'd need to replace those brushes? The more expensive solution would be to convert to manual hubs, but I'd like to avoid that if possible.

Hey sorry for the delay.

When I took my power locking hubs off I could see that the carbon brushes were smaller than the manual said they should be. So, I soldered on some new brushes but when I bent the copper plate spring back into the housing, the spring broke and I wasn't able to repair. There are no replacement part numbers I know of and I believe the manual said that if the brushes are below manual spec, replace the sub assembly i.e. the whole power locking hub.

I suspect that your mechanic has forgot to pin back the brushes and has broken them. Easy done if you're not familiar.

I have since installed aisin manual locking hubs and it's a simple process. There are different options - a bolt on version (cheaper, lighter duty) or bolt on with adapter ring (more expensive, heavier duty).

Happy to provide more info if you need.

 

[kgrove]

Hey sorry for the delay.

When I took my power locking hubs off I could see that the carbon brushes were smaller than the manual said they should be. So, I soldered on some new brushes but when I bent the copper plate spring back into the housing, the spring broke and I wasn't able to repair. There are no replacement part numbers I know of and I believe the manual said that if the brushes are below manual spec, replace the sub assembly i.e. the whole power locking hub.

I suspect that your mechanic has forgot to pin back the brushes and has broken them. Easy done if you're not familiar.

I have since installed aisin manual locking hubs and it's a simple process. There are different options - a bolt on version (cheaper, lighter duty) or bolt on with adapter ring (more expensive, heavier duty).

Happy to provide more info if you need.

I have to do some experimenting. I know with the engine off and key on, I can hear a hub lock motor spin if I push the button, but I don't know if it's one or both. I also don't know if they are actually engaging and disengaging, so it's possible my brushes are fine and it's something else that is causing the hub lock indicator to flash at me.

How does it work once you've converted to manual hubs? Do you have to do anything to keep the hub lock indicator indicator from flashing (I assume there is no sensor in place to tell it to illuminate)? When you manually engage the hubs and then push the h4 button, does that indicator illuminate to confirm you are in 4wd? And what about when you shift into low range - I thought I recalled the hub lock and transfer case automatically engage while in low... does the transfer case still automatically switch? I'm just trying to understand how all the electronics work and any little quirks that might exist after making the change to manual hubs.

 

[GreatScot]

I have to do some experimenting. I know with the engine off and key on, I can hear a hub lock motor spin if I push the button, but I don't know if it's one or both. I also don't know if they are actually engaging and disengaging, so it's possible my brushes are fine and it's something else that is causing the hub lock indicator to flash at me.

How does it work once you've converted to manual hubs? Do you have to do anything to keep the hub lock indicator indicator from flashing (I assume there is no sensor in place to tell it to illuminate)? When you manually engage the hubs and then push the h4 button, does that indicator illuminate to confirm you are in 4wd? And what about when you shift into low range - I thought I recalled the hub lock and transfer case automatically engage while in low... does the transfer case still automatically switch? I'm just trying to understand how all the electronics work and any little quirks that might exist after making the change to manual hubs.

Ask a friend to listen next to the hubs. It will be obvious if you can't hear one. The hub lock indicator could be flashing due to a problem with the 4WD ECU e.g. capacitors leaking on the circuit board. Do you hear any loud clicking around the steering column just after you have turned the key to turn the electrics on? You could always remove it, open it up and inspect. If there's a problem it's likely obvious.

To keep the hub lock indicator from flashing, disconnect the 4WD ECU. Note you do have to depress the hub lock button then depress the 4WD button to get the transfer case to engage after converting to manual hubs. (The transfer case may also engage automatically once you select low range - I'm not sure - but the electric hubs definitely don't). The hub lock dash light no longer illuminates after disconnecting the 4WD ECU, only the 4wd light illuminates.

I only recently converted and the only quirk is that the hub lock button has to be depressed with the 4WD button for the transfer case to engage. Nothing more.

 

[kgrove]

Ask a friend to listen next to the hubs. It will be obvious if you can't hear one. The hub lock indicator could be flashing due to a problem with the 4WD ECU e.g. capacitors leaking on the circuit board. Do you hear any loud clicking around the steering column just after you have turned the key to turn the electrics on? You could always remove it, open it up and inspect. If there's a problem it's likely obvious.

To keep the hub lock indicator from flashing, disconnect the 4WD ECU. Note you do have to depress the hub lock button then depress the 4WD button to get the transfer case to engage after converting to manual hubs. (The transfer case may also engage automatically once you select low range - I'm not sure - but the electric hubs definitely don't). The hub lock dash light no longer illuminates after disconnecting the 4WD ECU, only the 4wd light illuminates.

I only recently converted and the only quirk is that the hub lock button has to be depressed with the 4WD button for the transfer case to engage. Nothing more.

I did better than that. I had my mechanic put the car up on a lift that allowes the wheels to roll. When the hub lock and 4h switches are pressed, power gets to all 4 wheels, so the hub locks are engaging and the transfer case is pushing power to the front. When the switches are released, the front wheels are free spinning. While doing this, the hub lock indicator blinks the whole time and the 4h indicator light blinks with it when it is depressed. So - I have a functional 4WD system that likes to blink at me.

Unless I find something else, I’m suspecting the ECU. Where is it and what’s it look like? I’ll take a look and see if anything looks odd. The only thing that’s changed is it’s started getting very hot and my mechanics serviced the knuckles. I’m still thinking it’s more likely something in the electric lockers - weak enough signal to trigger the indicator lights going crazy but not so weak as to kill functionality…. Something along those lines.