1996 fzj80 dash vents not working properly. (1 Viewer)

[tayzoid1]

i am having a strange issue with my truck. I know a servo motor has gone out but I cannot for the life of me find which one. My ac and heat work great but it only comes out of the outside dash vents closest to the door. I can hear any door moving at all when I switch from feet to defrost or the mix. Can anyone point me in the direction? I would even be ok with Locking it into full dash vent, if it's a huge pain to change the servo.

Thanks for the help!

Quick rundown of the rig. 1996, fzj80, standard climate control unit, NOT auto. Everything else seems to work properly with the unit. Lthe ac is cool, and works well, just not enough air flow to circulate to the rest of the truck.

 

[tayzoid1]

Bump, anybody?

 

[tayzoid1]

So far, nothing is changing with the directional buttons on the climate control. Still searching and I'm not finding anything on the subject. My vents seem to be locked between dash panel and floor.

 

[canman]

I have the LX EWD manual with the auto, so I can't help from a electrical trouble shooting perspective, but like you said, the damper for the two middle vents is not opening. Some pics of the centre vent ducting when I had my dash apart.

 

[tayzoid1]

It seems like the actuator is on the driver side of the vent ducts? I appreciate the pics so much!

 

[canman]

I have many more if needed.

 

[tayzoid1]

could you try to find the center vent actuator and rods in your pics please? that would be a huge help. at least if i know which way they operate i may be able to lock them into the open position.

 

[canman]

I can't really tell where the actuator is, but in the second pic above, it looks like a lever arm for a flapper door on top of the white plastic box just to the left of the yellow fastener with the flat washer towards the right side of the pic.
In The pic below, it looks like the same arm behind the stereo to the right and another just below the two connectors in the pic below as well.

 

[tayzoid1]

Thanks! I will tear mine apart today and see what I can find!

 

[tayzoid1]

Found the issue! It seems that the actuator is locked up. Which I basically already knew, I just had to figure out which one it was. The actuator that controls the directional output of the ducts (dash vent, defrost, floor) is located on the driver's side of the center vent ducts. You can access it from the drivers floor board laying on your back. I took off the actuator and the lineages move freely and will now switch to all zones. Now just to find the actuator so I can get the buttons to work again. Thanks mud! And canman

 

[canman]

Glad to hear you found the actuator. Just curious, exactly where is it? Here is a pic from the driver's side, but I can't see anything that looks like an actuator.

 

[tayzoid1]

It is actually lower than this picture. It is just to the passenger side of the steering linkage if your laying in the drivers footwell. I took off three Phillips screws and it came right off letting the linkages move freely

 

[tayzoid1]

Basically on the bottom of the box

 

[adventurewagon]

For my first post, I'll jump in on this old thread just in case it helps anyone else looking for some more info on this. I just resolved the same issue - vent selection not working - in my 94 fzj80, and like the idiot I am, didn't take any pictures, but I might have some useful info.

Like tayzoid1 says, the motor/servo that moves the baffles in the vent system to divert air to different vents is accessible without dismantling the whole dash. All you need to do is take off the bottom piece of trim right below the steering wheel, and then, to really get at it, remove the piece of ducting that connects to the driver side vent. There's just one screw on the top left, then it can pop out.

You'll see a black servo box on the upper right of the drivers footwell. It's about 4" x 2" x 1/2" - it's a decent size, hard to miss. There's 3 screws holding it on, and they're pretty easy to get to with a short phillips screwdriver. Leave it plugged to run a quick test.

With the servo hanging there, turn the ignition to "on" (don't bother starting it) so the AC fans and stuff work. Try the vent selection buttons and see if the servo moves. If it does, then it's likely the actuator arms are jammed so check them to see that they move freely. If they do, then you might just be getting lucky with the servo after having removed it. Here's why:

I wasn't convinced my servo was dead. It just didn't seem like a part that would get the motor fried or anything. So I decided to take it apart. WORD OF CAUTION: keep track of the position the arm is in on the servo, as you'll want to put it back together in as close to exactly the same position as possible. Now take off the nut holding on the arm, and take out the 5 or 6 screws that are holding the box together. Inside you'll see a circuit board, a large gear and a small gear in the corner. SECOND WORD OF CAUTION: note the position of the big gear - same reason.

The magic is under the big gear. Pull it out. You'll see that there two sets of pins connected to the underside of the big gear that slide over contacts on the pcb to indicate what position the actuator arm is in. There was a bunch of grease that had gotten spread all over the contacts and pins - presumably from a lifetime of bumping around and little bits of lube trickling down from the large gear's shaft. I figured this could be the source of the issues if the grease was interfering with the contact between the pins and pcb. So I cleaned off the contacts and pins with a few q-tips and re-assembled the whole thing.

When reassembling, make sure the large gear and the actuator arm are in as close to exactly the same position they started from before you dismantled it. If not, the movement of the actuator arm will not align with the proper range of motion the parts that move the baffles can handle.

I plugged it back in, set the fan to high and selected a different vent scheme on the AC unit. And whaddya know - the servo works!

Now for re-mounting it, it's a bit tricky depending on what position the servo was previously stuck in... but you should be able to figure it out. Move the actuating arms to where the servo's arm fits in it's slot and the mounting points line up. Screw in one mount reasonably tight but leave the others for now to do a quick test, while you hold it in place with your hand. You'll want the wiggle room in case something is wrong. Switch between different vent schemes on the AC and make sure the unit doesn't push itself past it's allowed range of motion. If it does, you'll have to mess with the position of the servo's arm (no need to re-open and mess with the big gear's position at this point). The easiest is to set the vent to one of the extremes (all front vents or all defroster vent), and then work on getting the position right from there.

In case you're wondering, I learned all this the hard way

Whole process is pretty quick, and it saves you from having to source a new part!

 

[landcruiser3DP]

For my first post, I'll jump in on this old thread just in case it helps anyone else looking for some more info on this. I just resolved the same issue - vent selection not working - in my 94 fzj80, and like the idiot I am, didn't take any pictures, but I might have some useful info.

Like tayzoid1 says, the motor/servo that moves the baffles in the vent system to divert air to different vents is accessible without dismantling the whole dash. All you need to do is take off the bottom piece of trim right below the steering wheel, and then, to really get at it, remove the piece of ducting that connects to the driver side vent. There's just one screw on the top left, then it can pop out.

You'll see a black servo box on the upper right of the drivers footwell. It's about 4" x 2" x 1/2" - it's a decent size, hard to miss. There's 3 screws holding it on, and they're pretty easy to get to with a short phillips screwdriver. Leave it plugged to run a quick test.

With the servo hanging there, turn the ignition to "on" (don't bother starting it) so the AC fans and stuff work. Try the vent selection buttons and see if the servo moves. If it does, then it's likely the actuator arms are jammed so check them to see that they move freely. If they do, then you might just be getting lucky with the servo after having removed it. Here's why:

I wasn't convinced my servo was dead. It just didn't seem like a part that would get the motor fried or anything. So I decided to take it apart. WORD OF CAUTION: keep track of the position the arm is in on the servo, as you'll want to put it back together in as close to exactly the same position as possible. Now take off the nut holding on the arm, and take out the 5 or 6 screws that are holding the box together. Inside you'll see a circuit board, a large gear and a small gear in the corner. SECOND WORD OF CAUTION: note the position of the big gear - same reason.

The magic is under the big gear. Pull it out. You'll see that there two sets of pins connected to the underside of the big gear that slide over contacts on the pcb to indicate what position the actuator arm is in. There was a bunch of grease that had gotten spread all over the contacts and pins - presumably from a lifetime of bumping around and little bits of lube trickling down from the large gear's shaft. I figured this could be the source of the issues if the grease was interfering with the contact between the pins and pcb. So I cleaned off the contacts and pins with a few q-tips and re-assembled the whole thing.

When reassembling, make sure the large gear and the actuator arm are in as close to exactly the same position they started from before you dismantled it. If not, the movement of the actuator arm will not align with the proper range of motion the parts that move the baffles can handle.

I plugged it back in, set the fan to high and selected a different vent scheme on the AC unit. And whaddya know - the servo works!

Now for re-mounting it, it's a bit tricky depending on what position the servo was previously stuck in... but you should be able to figure it out. Move the actuating arms to where the servo's arm fits in it's slot and the mounting points line up. Screw in one mount reasonably tight but leave the others for now to do a quick test, while you hold it in place with your hand. You'll want the wiggle room in case something is wrong. Switch between different vent schemes on the AC and make sure the unit doesn't push itself past it's allowed range of motion. If it does, you'll have to mess with the position of the servo's arm (no need to re-open and mess with the big gear's position at this point). The easiest is to set the vent to one of the extremes (all front vents or all defroster vent), and then work on getting the position right from there.

In case you're wondering, I learned all this the hard way

Whole process is pretty quick, and it saves you from having to source a new part!

nice post. that’s really good intel.

 

[canman]

For my first post, I'll jump in on this old thread just in case it helps anyone else looking for some more info on this. I just resolved the same issue - vent selection not working - in my 94 fzj80, and like the idiot I am, didn't take any pictures, but I might have some useful info.

Like tayzoid1 says, the motor/servo that moves the baffles in the vent system to divert air to different vents is accessible without dismantling the whole dash. All you need to do is take off the bottom piece of trim right below the steering wheel, and then, to really get at it, remove the piece of ducting that connects to the driver side vent. There's just one screw on the top left, then it can pop out.

You'll see a black servo box on the upper right of the drivers footwell. It's about 4" x 2" x 1/2" - it's a decent size, hard to miss. There's 3 screws holding it on, and they're pretty easy to get to with a short phillips screwdriver. Leave it plugged to run a quick test.

With the servo hanging there, turn the ignition to "on" (don't bother starting it) so the AC fans and stuff work. Try the vent selection buttons and see if the servo moves. If it does, then it's likely the actuator arms are jammed so check them to see that they move freely. If they do, then you might just be getting lucky with the servo after having removed it. Here's why:

I wasn't convinced my servo was dead. It just didn't seem like a part that would get the motor fried or anything. So I decided to take it apart. WORD OF CAUTION: keep track of the position the arm is in on the servo, as you'll want to put it back together in as close to exactly the same position as possible. Now take off the nut holding on the arm, and take out the 5 or 6 screws that are holding the box together. Inside you'll see a circuit board, a large gear and a small gear in the corner. SECOND WORD OF CAUTION: note the position of the big gear - same reason.

The magic is under the big gear. Pull it out. You'll see that there two sets of pins connected to the underside of the big gear that slide over contacts on the pcb to indicate what position the actuator arm is in. There was a bunch of grease that had gotten spread all over the contacts and pins - presumably from a lifetime of bumping around and little bits of lube trickling down from the large gear's shaft. I figured this could be the source of the issues if the grease was interfering with the contact between the pins and pcb. So I cleaned off the contacts and pins with a few q-tips and re-assembled the whole thing.

When reassembling, make sure the large gear and the actuator arm are in as close to exactly the same position they started from before you dismantled it. If not, the movement of the actuator arm will not align with the proper range of motion the parts that move the baffles can handle.

I plugged it back in, set the fan to high and selected a different vent scheme on the AC unit. And whaddya know - the servo works!

Now for re-mounting it, it's a bit tricky depending on what position the servo was previously stuck in... but you should be able to figure it out. Move the actuating arms to where the servo's arm fits in it's slot and the mounting points line up. Screw in one mount reasonably tight but leave the others for now to do a quick test, while you hold it in place with your hand. You'll want the wiggle room in case something is wrong. Switch between different vent schemes on the AC and make sure the unit doesn't push itself past it's allowed range of motion. If it does, you'll have to mess with the position of the servo's arm (no need to re-open and mess with the big gear's position at this point). The easiest is to set the vent to one of the extremes (all front vents or all defroster vent), and then work on getting the position right from there.

In case you're wondering, I learned all this the hard way

Whole process is pretty quick, and it saves you from having to source a new part!

Welcome. That's the right attitude. Dive right in.