No ac no heat no blower 96 lx450 (1 Viewer)

[zzdudaka]

So the other night coming home i had the heat on high blower on high. All of a sudden it went out, nothing. No blower speed at all and therefore no heat.
Need some advice
Symptoms
1) no blower power on any setting
2) ac doest seem to click on when pressing ac button
3) does sound like control for floor, center, defrost are working. I hear temp noises when i change the setting with the truck off. Like to is moving the damper.
4) cant tell if temp slider is doing anything.

1) i pulled and tested all relays (5) from the drivers kick panel, all good
2) pulled and tested 2 relays on top of heater core behind glove box, both good
3) removed climate unit and changed setting to manual to test no dchange in issue
4) all fuses checked and good.

Dont have a fsm, have a haynes.
I have searched forum, before i randomly go online buying parts any advise on what to check next.
No post seems to show a 96 diagram, any advice on if it is the ac amp or ac system amp?

 

[zzdudaka]

PS - I have searched the forums for hours and see the same stuff about the transistor pack and fuses and relays... those things are not what I am looking for... I need additional info cause that doesnt seem to be the issue I am having.

Thanks!

 

[zzdudaka]

PICS PICS

OK so here are some pics... HELP ME!

The resistor pack seems to be somethign different on mine..
I bypassed it and still nothing.

Is there somethign else I am missing here?

Again relays are all fine, fuse is fine, bypassed resistor thingy, tested no good. Thoughts?


Purple arrow point to where relays are for those who may have similar issues.

 

[zzdudaka]

more pics just for reference to help others

Hope this help some folks with the same issue as me

 

[Gumby]

Did you check power and ground to the blower motor?

The motor gets switched power straight through the blower motor relay from the 40A heater fuse. You could jump that relay with no ill effects.

The relay gets switching power right from the 10A gauge fuse. It grounds through the AC amplifier.

The blower motor changes speed through the ground side of the circuit. The blower high relay bypasses the resistor block. If the blower doesn't work on high, the problem is not the resistor block. Again, I see nothing on the wiring diagram that suggests you can't jumper the ground side to ground, but I would disconnect the harness to do that as there is a splice that goes to the AC amplifier.

The system works on a lot of different fuses. I see power coming from the heater, gauge, ECU, Cig, tail and A/C fuses at different areas of the diagram.

 

[zzdudaka]

Thanks!

Will be checking all this after the holidays... The wifey seems to have started our holiday early without telling me till now.

What colors are the blower motor wires? At work at the moment so can look at 80. I also want to connect straigh 12v to it make sure the motor hasnt gone kaputz.

You are saying jump the relay down in the drivers kick panel or the big relay on top of the assembly?... that should send 12v straight to the blower motor yup.

Thanks!

 

[Gumby]

Blue yellow is power. Blue Red is ground at the blower motor.

The heater relay is the one to jump. The blower high speed relay is the other one. I don't know where they are located off the top of my head.

 

[outdoort]

This is the same exact problem I'm having right now, with the same exact symptoms, except that mine works when the engine is cold, then if I shut off the engine after it had warmed up for a while the heater or a/c (doesn't matter) and then try to turn it back on it usually doesn't work.

So this sounds like the same problem you have/had. Please report any solutions you may have found. In the mean time I will try Gumbys advice.

Also just so you all know : I got a 1997

 

[zzdudaka]

So after going through all of that and checking everythinb and I mean everythign... it just started working again. The cause has not been posotively identified, but I suspecting that water had gotten into one of the climate related computers.
Secifically the one down by the throttle pedal. As I was searching posts I found tsomeone else had essentially stated that there is another computer down by the gas pedal. ... and cruisers have a known winshield leak that basically lets water seep into that computer... the assembly is open at the top and sealed at the bottom. Again I dont know this was my issue but I assume it was as I had recently been mudding and pressure washed both the outside AND inside of my cruiser. I dont know if this helps at all but I will see if I can find the thread and email ya... in the mean time search for windshield leak climate AC etc.

 

[zzdudaka]

To better describe my issue about a week after washing it. I was driving along and it all went out.. about 2 weeks later it would work intermittantly each time I turned the truck off and then back on i mightt get lucky if it was one of those lucky times occasionally it woudl just quit, then 10 seconds later start again.. I took everythgin apart and tested and couldnt find anythign... The only part that has not been looked at is this other computer that I wasnt aware of down by the skinny pedal.

 

[zzdudaka]

This thread talks a little about the water issue.
https://forum.ih8mud.com/80-series-tech/226282-hvac-system-stumps-dealer.html

 

[GringoBob]

I've got the exact same problem. How did you finally resolve this issue ???
Thanks!
GringoBob

 

[GringoBob]

So the other night coming home i had the heat on high blower on high. All of a sudden it went out, nothing. No blower speed at all and therefore no heat.
Need some advice
Symptoms
1) no blower power on any setting
2) ac doest seem to click on when pressing ac button
3) does sound like control for floor, center, defrost are working. I hear temp noises when i change the setting with the truck off. Like to is moving the damper.
4) cant tell if temp slider is doing anything.

1) i pulled and tested all relays (5) from the drivers kick panel, all good
2) pulled and tested 2 relays on top of heater core behind glove box, both good
3) removed climate unit and changed setting to manual to test no dchange in issue
4) all fuses checked and good.

Dont have a fsm, have a haynes.
I have searched forum, before i randomly go online buying parts any advise on what to check next.
No post seems to show a 96 diagram, any advice on if it is the ac amp or ac system amp?

I've got the exact same problem. How did you finally resolve this issue ???
Thanks!
GringoBob

 

[CruiserCarter]

Sorry to dig up an old thread but, I’ve read thru this and many other posts and no one seems to say what they’ve changed to fix the OP symptoms? I changed resistors, changed climate control unit, and tested the blower resistor which I believe is bad as the continuity test says.

 

[CruiserCarter]

 

[CruiserCarter]

Those are the 2 parts I’ve pulled, top pic is the blower resistor? And bottom is the ac blower motor resistor? I’m not sure the FSM I have isn’t all that great in detail.

 

[zzdudaka]

Honestly I never figured it out... it just started working. Reference the water leak issue and clean the sunroof drains.

It’s a crap shoot... I mean I tested everything and replaced nothing and it went back to working.

 

[Inthefive555]

Wild. I am here in this situation myself and found nothing wrong with any of the listed components. I'll be digging into the wiring soon and hopefully one of us can find something more conclusive for those whose problem isn't the ecu.

 

[CruiserCarter]

Okay I’ll try that, haven’t noticed any wet spots anywhere, my 98 4runner had that problem. I’ll be spending a whole day to diagnose this blower problem so I’ll post about it on the weekend!

 

[CruiserCarter]

So after a busy couple weeks I took 2 minutes to pull the system amplifier or a/c amplifier out from under the steering wheel column and looks like water has gotten inside it and shorted and rusted some circuits.