'95 HDJ81 Cruise Control Question

[Turbobrick211]

So I finally got around to taking a look at the cruise control actuator. It looks different than the one in the picture above. The throttle cable from the pedal attaches to the spool, and another cable attaches between the spool and the main throttle linkage. Everything rotates freely. All the wiring connectors are clean and connected. So what can I do at this point to diagnose the electrical part of the system?

 

[MontyAndCruiser]

Waitaminute... is this why my CC does a weird surge then immediately shuts off? Because of a speed limiter?

 

[pasquinel]

Waitaminute... is this why my CC does a weird surge then immediately shuts off? Because of a speed limiter?

Mine does. I tried a US module swap but cruise light would not even turn on. Switched back to JDM box and I am limited to 69mph

 

[Dusten]

Mine does. I tried a US module swap but cruise light would not even turn on. Switched back to JDM box and I am limited to 69mph

Get bigger tires lol.

I can do 75 on the cruise now.

An Aussie cruise unit should work.

 

[pasquinel]

Get bigger tires lol.

I can do 75 on the cruise now.

An Aussie cruise unit should work.

I was thinking about opening the module to see what I could find. Maybe mod to remove governor. Anyone done this? I would also buy an Aussie unit, ESPECIALLY if it comes with an Aussie FSM!!!

 

[Dusten]

I was thinking about opening the module to see what I could find. Maybe mod to remove governor. Anyone done this? I would also buy an Aussie unit, ESPECIALLY if it comes with an Aussie FSM!!!

My guess is the module takes the signal from the speed sensor. So it's possible if you added a resistor inline to lower the voltage it sees you could fool it. But I'd want to see a diagram first.

 

[jellis]

@Turbobrick211 you need to run the diagnostic tests in the FSM and see what the blinking lights say. The CC is the only computer on your early rig with diagnostics! The VSS is a known failure point on these early rigs and unfortunately they are NLA.....you can rig an entirely different VSS system based on GPS, or fix the hall-effect sensor in your current VSS--both options are discussed at length in this thread:

90-92 Cruise Control Fix

Hello all, i've been reading here for years but this is my first post. I've got a 90 HDJ81 with cruise control problems. Mr. Toyota no longer makes the speed sensor for the 91-92 80 series (or 90-92 HDJ81) and call me a soft but having the CC is awesome for driving our rigs long distance. I...

forum.ih8mud.com

I swapped my CC computer for an early 3FE US-equivalent (88240-60050) and it worked great and eliminated the stupid governor.

 

[Ultrashock]

I also just performed this swap. Pic below (on the left is the original, the one on the right I acquired from Cruiser Parts). No more governor for me!

 

[MontyAndCruiser]

Hmmm... is the grouping set by the same sort of spacing i'd expect to see in US market? 91-92, 93-94, 95-97? Or do i just need to play around in some parts diagrams to figure out which is which? Mine is a 94, so i guess i could test the one from my FZJ.

 

[Dusten]

@Turbobrick211 you need to run the diagnostic tests in the FSM and see what the blinking lights say. The CC is the only computer on your early rig with diagnostics! The VSS is a known failure point on these early rigs and unfortunately they are NLA.....you can rig an entirely different VSS system based on GPS, or fix the hall-effect sensor in your current VSS--both options are discussed at length in this thread:

90-92 Cruise Control Fix

Hello all, i've been reading here for years but this is my first post. I've got a 90 HDJ81 with cruise control problems. Mr. Toyota no longer makes the speed sensor for the 91-92 80 series (or 90-92 HDJ81) and call me a soft but having the CC is awesome for driving our rigs long distance. I...

forum.ih8mud.com

I swapped my CC computer for an early 3FE US-equivalent (88240-60050) and it worked great and eliminated the stupid governor.

The cost of that part is not worth it to me. Jeeebus. I can run 75 as is. That's fast enough.

 

[nickolai]

Coming off cruise in my 1994 JDM HDJ81 always had a bit of a jolt - i think the quadrant in the box 'snaps back' pretty quickly. Getting the slack out of the cable at the cruise box and at the injector pump helped.

Mine sits on 100km (indicated) no problem. I don't want to go faster than that. In fact I use it mostly on roads near me that have had their speeds dropped to 60KM or 80KM from 100 as the po-po are ticketing people all over the shop!

 

[Dusten]

Coming off cruise in my 1994 JDM HDJ81 always had a bit of a jolt - i think the quadrant in the box 'snaps back' pretty quickly. Getting the slack out of the cable at the cruise box and at the injector pump helped.

Mine sits on 100km (indicated) no problem. I don't want to go faster than that. In fact I use it mostly on roads near me that have had their speeds dropped to 60KM or 80KM from 100 as the po-po are ticketing people all over the shop!

100km is 69mph in my rig which is just under. A 70mph speed limit. Which is why 110km doesn't bother me. 75 in a 70 is plenty.

 

[jellis]

Speed limits on freeways in Southern Utah are 80MPH. I remember the limit being lower than 75, you are right that probably want worth it if that's the case!

If you're cheap and want to fiddle, can also solder in a resistor to R507 on the board as described thoroughly this post:

HDJ81 Cruise control top speed

On a trip to Kelowna this weekend, I discovered my 1HDT appears to have the cruise control governed to a top speed (via GPS) of approx 120 kph (corrected for my larger than stock tires). Anyone else noticed this on their HDJ81? I've had the truck a few months and this is the first time I...

forum.ih8mud.com

 

[Dusten]

Speed limits on freeways in Southern Utah are 80MPH. I remember the limit being lower than 75, you are right that probably want worth it if that's the case!

If you're cheap and want to fiddle, can also solder in a resistor to R507 on the board as described thoroughly this post:

HDJ81 Cruise control top speed

On a trip to Kelowna this weekend, I discovered my 1HDT appears to have the cruise control governed to a top speed (via GPS) of approx 120 kph (corrected for my larger than stock tires). Anyone else noticed this on their HDJ81? I've had the truck a few months and this is the first time I...

forum.ih8mud.com

This was basically what I eluded to earlier. Fooling the module.

 

[IanB]

100km is 69mph in my rig which is just under. A 70mph speed limit. Which is why 110km doesn't bother me. 75 in a 70 is plenty.

100km/h is actually just 60mph, unless you're accounting for larger tires and saying that's your GPS speed when 100km/h is indicated. 100km/h isn't fast enough for safe driving on highways with 100km/h speed limit IMO.

 

[jellis]

Yeah that's it, 109 km/h is ~68mph which is pretty slow when the speed limit is 80mph.

Also, I don't drive an 80 because I enjoy arbitrary limits in life.

 

[MontyAndCruiser]

I don't really love to drive 80s over say 72-75mph, but i'd like to be able to do 75mph with the cruise control if i'd like to, since the whole reason i have these things is for long trips.

 

[Dusten]

I can go 75. Just need tires.

 

[rovingCoast]

I also just performed this swap. Pic below (on the left is the original, the one on the right I acquired from Cruiser Parts). No more governor for me!

View attachment 2965039

Is this a simple part swap, or is there a write-up somewhere I can look at to see what's involved? I don't *mind* my max 112km speed on my JDM cruiser but I'd like to maybe have the choice to get all the way up to *shock* 120km/h. Thanks!

 

[jellis]

It is a drop dead simple part swap, IIRC the computer is in the RH kickpanel.....undo the connector, probably a bolt for a bracket, replace with new computer, done.