Those Of You With Field Monitor Units

...Nor do I see how re-routing a ground cable to another ground position would change a thing, let alone how the readout receives and displays information - it's either grounding out or it's being shorted out. Simply put, ground is just a safety net. It carries no current unless a malfunction occurs.

Sorry, I should have said "rerouting a wire to ground". Still can't remember which one it was though.

The G35 was essentially the NA version of the Nissan Skyline 350GT and share common parts including climate control. Both were built on the same line in the Kaminokawa plant (Japan). It's a safe bet the 4Runner - also built in Japan and distributed worldwide - has DNA for metric and imperial in its electronics.
 
Installed my FMU this afternoon. I had pre-run the wires from the clock, ABS module, and the ambient temp sensor last week, so today was just about installing and wiring the actual unit.

Was fairly easy except my '97 4Runner doesn't have the "blue plug" referred to in most of the on-line install threads. But it was easy to figure out as soon as I found a constant 12v and a switched 12v (tapped into the sunroof control and the original map light circuit positive).

I went from a 2-button sunroof model to a 2-button sunroof FMU so that helped.

One issue is the temperature reading is incorrect. It is reading -7 celsius when the temperature is actually +7 celsius (according to my phone and my bones). So, either the OEM ambient temp sensor from later-model 3rd gens isn't compatible with the FMU, or I have a bad one. Will look into it later....

I read somewhere that the polarity of the two wires from the temp sensor doesn't matter. Anyone have any intel on that?

PS - I dig the "moving 4Runner" action when the vehicle is in motion. Totally worth the trouble of tapping into the ABS module and fighting with the A-pillar handle bolts.
 
Installed my FMU this afternoon. I had pre-run the wires from the clock, ABS module, and the ambient temp sensor last week, so today was just about installing and wiring the actual unit.

Was fairly easy except my '97 4Runner doesn't have the "blue plug" referred to in most of the on-line install threads. But it was easy to figure out as soon as I found a constant 12v and a switched 12v (tapped into the sunroof control and the original map light circuit positive).

I went from a 2-button sunroof model to a 2-button sunroof FMU so that helped.

One issue is the temperature reading is incorrect. It is reading -7 celsius when the temperature is actually +7 celsius (according to my phone and my bones). So, either the OEM ambient temp sensor from later-model 3rd gens isn't compatible with the FMU, or I have a bad one. Will look into it later....

I read somewhere that the polarity of the two wires from the temp sensor doesn't matter. Anyone have any intel on that?

PS - I dig the "moving 4Runner" action when the vehicle is in motion. Totally worth the trouble of tapping into the ABS module and fighting with the A-pillar handle bolts.

I wired mine up several years ago but it never turned on and I have a feeling I didnt do something right. Do you have any pics of how you wired up the unit with the wires up in the headliner. I tapped into the clock, and abs on the passenger side, I think I just didnt wite up correct on the wires I'm the headliner. Any help would be appreciated!
 
...Do you have any pics of how you wired up the unit with the wires up in the headliner. I tapped into the clock, and abs on the passenger side, I think I just didnt wite up correct on the wires I'm the headliner. Any help would be appreciated!

I didn't take any pics, but the wiring is pretty basic. Just remember that there are two distinct "areas" in the FMU. One area is the actual FMU itself which has its own molex connector, and the other "area" is the harness for the map lights (and if equipped, sunroof controls).

the molex connector that plugs into the actual FMU has nine wires:

1) White/black connects to ground (I ran mine to body)
2) Blue/yellow connects to constant 12v (mine to the original map light +)
3) White/red connects to switched 12V (mine to the switched 12v in the sunroof molex - there are a couple of switched 12v options in the overhead console area, so just do some probing and find the one that's easiest to access)
4) Green/orange connects to the speed sensor wire from the ABS module
5) Solid green connects to the solid green at the back of the digital clock
6) Solid blue connects to temperature sensor
7) Yellow/black connects to temperature sensor
8 and 9) The final two wires (I forget what colours they are) are unused.

There are a few different configurations for map light/sunroof options depending on what your 4Runner came with:

No sunroof
One-button sunroof
Two-button sunroof

You may have to experiment to get this part right. In my case I was putting a two-button sunroof FMU in a two-button sunroof vehicle It was basically plug and play except the constant 12v+ for the map lights had to be connected from the original constant 12v map light wire, which has its own molex connector. Alternately you can pop the original map light 12v out of its molex and put it in the blank space in the donor sunroof/map light molex, but I didn't have a pick for that. Plus I was getting hungry.

The only thing I did wrong was I mistakenly spliced the constant 12v+ from the original map light circuit to the new map light circuit ground (instead of 12v+), blowing the fuse. So make sure you have a couple of extra 15a fuses to replace the "dome" fuse in your fuse box. Or just pay attention, which I didn't!

Not to insult your intelligence, but there is a "lights off" switch on the FMU. When i first test-wired mine up there was no life, but it was just the switch was "off". So it could be as simple as that (or dead/missing bulbs in the FMU).
 
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One other thing - the map light reflector shrouds in my FMU were kind of dull and corroded. I lined them with tinfoil and now those tiny bulbs give off more light than 1000 suns!
 
Sorry, I should have said "rerouting a wire to ground". Still can't remember which one it was though.

The G35 was essentially the NA version of the Nissan Skyline 350GT and share common parts including climate control. Both were built on the same line in the Kaminokawa plant (Japan). It's a safe bet the 4Runner - also built in Japan and distributed worldwide - has DNA for metric and imperial in its electronics.
While the 4Runner/surf were manufactured globally for the same 3rd gen years, the FMU was never offered in a 4Runner and therefore never offered in a market that used imperial system. The FMU was also not a standard feature on all the surfs. The company that manufactured the FMU wasn’t based in an imperial measurement country either.
 
One other thing - the map light reflector shrouds in my FMU were kind of dull and corroded. I lined them with tinfoil and now those tiny bulbs give off more light than 1000 suns!
I have a roll of duct sealing tape (the aluminum style) for that purpose. I use it on all my cars, basically. Incandescent warmth, LED brightness.

-Charlie
 
One issue is the temperature reading is incorrect. It is reading -7 celsius when the temperature is actually +7 celsius (according to my phone and my bones). So, either the OEM ambient temp sensor from later-model 3rd gens isn't compatible with the FMU, or I have a bad one. Will look into it later....

I read somewhere that the polarity of the two wires from the temp sensor doesn't matter. Anyone have any intel on that?
Correct that the polarity doesn't matter. The resistance curve on the FMU temp sensor is different than the OEM Limited outside temp sensor. You can plug in the correct FMU temp sensor into the plug with a bit of modification. Sorry, I don't have the PN right now...

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-Charlie
 
Correct that the polarity doesn't matter. The resistance curve on the FMU temp sensor is different than the OEM Limited outside temp sensor. You can plug in the correct FMU temp sensor into the plug with a bit of modification. Sorry, I don't have the PN right now...


-Charlie

Thanks for posting this. I returned to this thread to say that I was wrong! The sensor is indeed proprietary. The sensor from the 99+ 4Runners is off by about 16 degrees celcius!

The correct sensor for the FMU is 83482-35010 (Sensor, Outer). Not sure if it's available through Toyota North America.
 

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