Improve your A/C pre-2003? (1 Viewer)

[blatant]

@knewstance. What year is your 100...1998?

From OE standpoint, you should haves aux fan. Strange it would be missing, Unfortunately.

 

[knewstance]

@knewstance. What year is your 100...1998?

From OE standpoint, you should haves aux fan. Strange it would be missing, Unfortunately.

Yes, 1998. Manufacture date of 6/1998. It was always taken to a shop for all work before my ownership. It seems to me that it came from the factory in it's current fan-less state - a deletion to this extent would be far more than most shops would be willing to do.

On the bright side, mine is so rare, being 1 of 14, 327. This must increase my value exponentially.

 

[blatant]

Im sure you already know but if that's the case @LandCruiserPhil can help you out with his fan kit.

 

[MadKel]

1998 LC did not have rear A/C available. While LX470 did.

 

[flintknapper]

Since I already bought my fan, it looks like I will be needing the hardware and bushings in this post, and then I will have to figure something out with the wiring. I'd like it to be integrated to the pressure switch so my wife can drive and not have to worry about turning the fan on and off, so I probably will try to go another route than listed in LCP's 2003+ kit.

It appears from the pic you posted that your vehicle has a Binary Switch and Connector (no provision to add pigtails). So in order for an Aux Fan to work via high side line pressure, you would need to replace the Binary Switch with a Trinary Switch, add two pigtails, a relay and associated wiring. It could be wired to include manual operation (or shut off) as well...but would come on (and go off) automatically as the factory intended.

 

[hoser]

@flintknapper Good catch. There are two options in '98: 1) single air conditioner.... w/ binary switch and 2) dual air conditioner w/ trinary switch.

The trinary switch is quite spendy through Toyota ($100+) but can be had from Denso or aftermarket for much less. I don't know the procedure of changing out the switch... might have to drain the system and refill? That could be substantial added cost.

 

[knewstance]

So I'm seeing that I would need these parts plus the extra wiring and relay. Anything missing?

Trinary Pressure Switch. I read that the Corolla used the same one as the LC on another one of these threads.
Trinary connector -- searching for a source....
Condenser fan connector -- also searching for a source...

Any ideas where to find these connectors? I'd prefer to not resort to cutting them out off at a junkyard.

 

[flintknapper]

Delete

 

[nukegoat]

Have you checked the actual low-side pressure with real manifold gauges? You can get a perfectly workable set of gauges off Amazon for ~$35. Look for it to be 35-42 psi with the truck warmed up and the AC on full. If it's less, than you need R-134a. Right now you are just guessing....

Thats not how refrigerants work

 

[knewstance]

So I'm seeing that I would need these parts plus the extra wiring and relay. Anything missing?

Trinary Pressure Switch. I read that the Corolla used the same one as the LC on another one of these threads.
Trinary connector -- searching for a source....
Condenser fan connector -- also searching for a source...

Any ideas where to find these connectors? I'd prefer to not resort to cutting them out off at a junkyard.

These connectors are near impossible to find right now. I'm just going to wire up a simple relay and switch and then if I ever find the connectors, I will make things more like factory using a trinary switch.

 

[knewstance]

So I just finished installing the fan and setting up the wiring harness and relay. Video for proof! lol



Now my goal is to delete the switch so that it turns on and off with the AC system. I fear that when my wife or someone else is driving my LC, they will fail to turn the switch off resulting in a dead battery.

Any ideas which wire in the AC system would be best to tap into to get this set up? Am I better off using an Add-A-Fuse off an AC component or something?

 

[knewstance]

@flintknapper @blatant @hoser @medtro

Any ideas on this wiring? I'm thinking the binary AC pressure switch?

 

[medtro]

Video not working.

 

[knewstance]

Video not working.

Updated. It's just a video of the fan running using the switch that came with the relay.

 

[flintknapper]

@flintknapper @blatant @hoser @medtro

Any ideas on this wiring? I'm thinking the binary AC pressure switch?

IF you want automatic operation I would recommend duplicating the factory set up (use a trinary switch) which would operate the fan only when needed (within a certain pressure window). This could also be done if you can find a temperature switch that corresponds to the high side pressure (for off and on operation).

Some folks have tapped into A/C clutch circuit so that any time the A/C clutch is engaged...the fan also runs, but I don't like that method for several reasons.

Your binary switch is the first ever I have seen on a 100 Series (or even most 80 series). Unfortunately, I believe you would have to evacuate your system in order to install a Trinary switch. I will look in my FSM when I get the time and see if says anything about that, but I don't think the mount for the switch has a schrader valve.

 

[knewstance]

IF you want automatic operation I would recommend duplicating the factory set up (use a trinary switch) which would operate the fan only when needed (within a certain pressure window). This could also be done if you can find a temperature switch that corresponds to the high side pressure (for off and on operation).

Some folks have tapped into A/C clutch circuit so that any time the A/C clutch is engaged...the fan also runs, but I don't like that method for several reasons.

Your binary switch is the first ever I have seen on a 100 Series (or even most 80 series). Unfortunately, I believe you would have to evacuate your system in order to install a Trinary switch. I will look in my FSM when I get the time and see if says anything about that, but I don't think the mount for the switch has a schrader valve.

It was about impossible for me to find the connector plug for a trinary switch. The pressure switch with the trinary receiver is available but the plug was the issue. That was my original goal, but I had no luck finding a plug.

What is your reasoning behind the AC clutch circut method?

 

[flintknapper]

It was about impossible for me to find the connector plug for a trinary switch. The pressure switch with the trinary receiver is available but the plug was the issue. That was my original goal, but I had no luck finding a plug.

What is your reasoning behind the AC clutch circut method?

If you tap into the AC clutch circuit your fan will run any time the clutch engages. That might sound like a logical and good thing...but there are times when you don't really need or want the fan to be running. The fan generally would not be running when you are at highway speeds (most climates, most conditions). You don't need the fan running in the wintertime when you use your A/C to clear windshield fogging, etc...

So...its an unnecessary taxation on the electrical system and only accelerates wear on the fan. Then there is amp draw on the circuit itself. This may or may not present an issue but you would have the fan vying for power at the exact same time the A/C clutch is trying to engage (and stay engaged).

If running the fan always concurrent with the A/C clutch being engaged were a good thing...then Toyota surely would have done it that way.

It is not a method I would recommend.

If you don't want to convert yours to a Trinary switch (or externally mounted temperature switch), then leave it 'manual' and wire it such that it gets its power from an ignition on source. That way when the engine is shut down the fan can not continue to run on and drain the battery...but honestly...you couldn't help but hear it running.

The factory set up utilizes a Trinary switch located in the high side line. It senses pressure that causes the fan to engage at a certain pressure and cut out again once that pressure has lessened to a certain point. It is automatic in function and an added benefit it that the fan will continue to 'run on' for just a while after you shut the engine down (if temps are high enough) which aids in cooling the system as it 'equalizes'. This means faster 'cooling/recovery' for times when you just run in someplace for 10-15 minutes and then are back in your vehicle.