Cruise Control Help

[robar1100]

My cruise control did not work when I purchased my LC(91 FJ80). The CRUISE light comes on when I depress the button but would not engage when I try to SET the speed.
I Rebuilt my motor recently and thought I give the cruise control a try. Woohoo, it was working.
The next day, I tried the cruise control again and it did not work. The light comes on but the cruise control will not engage.
I have tried to engage the cruise control the last 3 days to no avail.
Any thoughts on why it won't engage?

 

[sea bass]

I have a 92 I had the same problem the cruise control on a fj 80 is pretty complicated you have a speed sensor on your speedometer cable on the transmission a speed control computer under the dash and your actuator under the hood I had some problems with mine and it was my speed sensor on the transmission if you look on your speedometer cable you'll see a little square box a lot of lot of times it gets cracked and water gets in there and sort it out mine did the same thing as yours the cruise light comes on but did not engage the speed sensor was my problem I pulled one out of the junkyard and all is well there is a series of tests you can do inside with your cruise control lever if you have a manual.

 

[sea bass]

Here is a picture of the speed sensor

 

[sea bass]

I forgot to mention the cruise control also ties into your parking brake switch and your neutral start switch on the transmission

 

[robar1100]

I forgot to mention the cruise control also ties into your parking brake switch and your neutral start switch on the transmission

View attachment 1239776

Sea bass, thank you I will look t all your suggestions

 

[tabledrain]

i have the same problem.. i best go have a look.

 

[jaymar]

Since we're on the topic--mine sometimes works, sometimes flashes the green light and doesn't work. It also sometimes (when working) sputters on road bumps. Does this behavior narrow down the possibilities?

 

[sea bass]

Not really.the cruise control is a very complicated system on the fj80,s you just have to start trouble shooting one thing at a time

 

[sea bass]

Oh a Fsm helps to.

 

[Sarmajor]

My 92 truck has a full electric speedo so no cable drive to the speedo, only wires.
There are two speed sensors on the HDJ81 models.
The only issue I have had with the cruise control is over current reported by the drive motor. Usually fixed up by lubing the mechanism with a bit of ATF.

 

[Sarmajor]

Flashing the green light is the fault code. Count the flashes and use the FSM or google to find out why it is unhappy.

 

[bloc]

On the 1FZ trucks the VSS (vehicle speed sensor on the transmission) doesn't feed the speed signal to the cruise/ECU/TCU directly.. it sends a signal to the speedometer, which is both used by the speedo for the needle and cleaned/shaped into a signal that the other accessories can use.

If a 3F truck doesn't have a physical speedometer cable, you can probably assume the speed signaling works the same way.


Mine flashed with no fault code. Just steady on/off when I tried to engage it. In my case it turned out to be a bad stop light switch.. the switch has two circuits and the one for the brake lights worked fine, so I assumed the other part was ok. I was wrong.

97 LX, for the record.

 

[Slowguy432]

Great topic - Im going to use this to figure mine out.

 

[sea bass]

3Fe 80,s have a physical speedo cable.

 

[White Stripe]

3Fe 80,s have a physical speedo cable.

Sea Bass do u know if the cruise control on a 3fe 80 series gets its speed signal from the cluster? Or is it the speed sensor exclusively?

 

[sea bass]

i

Sea Bass do u know if the cruise control on a 3fe 80 series gets its speed signal from the cluster? Or is it the speed sensor exclusively?

i believe it gets it from the speed sensor only troubleshooting my cruise control was a pain in the butt

 

[Mixelplix]

If you have a solid green cruise light, and it doesn't work it's almost definitely the VSS connected to the output shaft.

It's a hall effect sensor, so cleaning it may be an option. The wires run up and over the transfer case, so check them for damage. I don't believe the VSS is available new anymore.

 

[sea bass]

If you have a solid green cruise light, and it doesn't work it's almost definitely the VSS connected to the output shaft.

It's a hall effect sensor, so cleaning it may be an option. The wires run up and over the transfer case, so check them for damage. I don't believe the VSS is available new anymore.

no there not available anymore and they are getting a lot harder to find used

 

[White Stripe]

If you have a solid green cruise light, and it doesn't work it's almost definitely the VSS connected to the output shaft.

It's a hall effect sensor, so cleaning it may be an option. The wires run up and over the transfer case, so check them for damage. I don't believe the VSS is available new anymore.

Yea I have a solid green light. I bet my sensor is bad too.

 

[sea bass]

Yea I have a solid green light. I bet my sensor is bad too.

a lot of times the plastic casing cracks and water gets in there causing it to go bad