[4Runner4Leon]

Final product upfront:



One of the things I miss in our 4Runner is having an outside (ambient) temperature gauge, something that I’ve come to rely on in our other cars. So the more I stared at the useless “Passenger” area of the center dash switch panel (below), the more it called for me to upgrade it with a digital thermometer. And while at it, why not add a digital voltmeter as well.



I started out by dremeling out the whole rectangular “Passenger” portion. Fortunately there is a slight groove all around it, so that was my guideline for the dremel. The groove is good at helping hide mistakes (within reason!). I also ground away all the plastic webbing behind the “Passenger” portion of the panel.



Here is the section removed and filed smooth. I used some fine sandpaper to bring the plastic edge to a finished appearance:



I made a smoked window for the gauges out of a center cluster panel from a 2001 Lexus GS430 – it’s smoked and flat, and I found one at a junkyard. You can find one in most any other car these days, I just picked that one because I have this model Lexus and saw that it would be the perfect donor. I cut it in half to give me a spare in case I screwed up; here is the half I started with:



I used a sander to shape the plastic piece to be just slightly larger than the opening I made in the center switch panel:



It looks way too small in the photo, but it’s an optical illusion. I then hot-melt-glued the smoked plastic to the panel:





I needed some type of a holder for the actual gauges, so I went with a 3D printed solution to build a frame that would fit tightly inside the panel, and would hold the gauges well. You can use whatever you have handy to make a similar mount.







Frame installed in the switch panel:



Here are the gauges installed in the frame:




For the gauges, I wanted to go with 0.36” LED gauges in green. It took me a while to find a decent pair of gauges. To start with, it’s hard to find a digital gauge in Fahrenheit. The first one I ordered from Amazon was DOA. I ordered another one, but it had a leading zero, so 65F would display as 065. I finally ended up going with this DROK item:

Digital Meter DC 12V 24V Red/Blue/Yellow/Green Led Thermometer -67~+257 Fahrenheit Degrees Digital Temperature Meter for Car/Indoor/Outdoor/Pet House/Greenhouse etc



I also went through some trials with the voltmeter. One was supposed to be green but was more yellowish, so it clashed with the thermometer. Another one started smoking when connected to 12V. I finally settled on this one, also from DROK:

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1.



When I had them both on, the color match was good, but the voltmeter was way brighter than the thermometer. So I made a second smoked plastic piece, to place over the voltmeter:



Using window film might have been an easier option, but I didn’t have any film and I had the smoked plastic on hand.

After inserting the gauges into the frame, and the frame into the switch panel, I used some epoxy to stake everything together.



I tied all the wires together into a connector (five terminals), to make any future dash bezel removals easier:



On the vehicle side, I tapped into a switched 12V source, and a ground (both from the power outlet wiring behind the dash). I also routed the sensor probe wires to the dash bezel area. I used a 3 meter temperature probe harness, and placed the probe behind the front bumper. Here is the probe I bought:
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Here are all the vehicle-side wires assembled into a connector to match the one in the switch panel (the white thing towards the right):

[4Runner4Leon]

And here is the final result. Key off:



Key on:

.

I was surprised and pleased to see my temperature gauge agree so well with my “engine off” transmission temp gauge:



Overall I’m very pleased with the result. The only surprise so far has been that I designed and assembled everything looking straight at the dash bezel. But being on the tall side, I found that from my sitting position in the truck, the very top of the display gets cut off, so I can’t distinguish between a 1 and a 7 without moving my head down slightly. But I can live with that.

I do wish that I could find a source for good quality gauges, and not have to go through the non-working and smoking gauges. Time will tell how long these DROK gauges last, hopefully they’ll last a long time.

EDITED TO ADD:

I found that I needed to change the outside temperature probe location. It's either getting too much cooling at speed, or too much soak-back when stopped. Regardless, it reads 60F at 40 mph, and creeps up to almost 70F at a red light. Since I know it was nowhere near 70F this morning, I am guessing it's radiator/engine soak-back. So I'll probably move it somewhere into the fenderwell area.

[kolelt]

Dude. That’s awesome work. Nicely done mate.

[Vansnxtweek]

Wow man great job!! I often wish I had a temp display as well. That turned out so good!!!

[Tyler James Inc]

HOLY SHÍT!!!
Dude. Nice work.
Do you have a 3D printer you used to make the board frame?

[4Runner4Leon]

Originally Posted by Tyler James Inc

HOLY SHÍT!!!
Dude. Nice work.
Do you have a 3D printer you used to make the board frame?

Thanks buddy! And yes, the 3D printer was a present from my son last year, I must have raised him right . Note the trans temp gauge mount, that's 3D printed as well.

[Mighty Buffalo]

That is awesome. I've been trying to find something that looks clean and near factory. I had an autodimming mirror, but it was shorting out some other stuff, and I had to take it out.

[marcus clarkus]

Wow that looks super clean nice job!!!! I would copy you except that I already stuck a bluetooth mic in the spot. I'm going to keep my eyes peeled for a rear view mirror with a compass/thermometer instead.

I still need something to fill the spot where the ECT button usually goes...

[JZiggy]

Hats off to you, Leon my friend!!

[dogtail]

Nice, I miss my outside temp reader that I had in my 99 LTD, my 99 SR5 doesn't have one. Especially handy when its black ice season if temp hits 32, gotta be careful. I've been guessing.

[4Runner4Leon]

Originally Posted by marcus clarkus

Wow that looks super clean nice job!!!! I would copy you except that I already stuck a bluetooth mic in the spot. I'm going to keep my eyes peeled for a rear view mirror with a compass/thermometer instead.

I still need something to fill the spot where the ECT button usually goes...

Well the ECT area would be perfect for one digital gauge . Or you can move your mic there, and do the rest like I did.

[marcus clarkus]

Originally Posted by 4Runner4Leon

Also, I found that I need to change the temperature probe location. It's either getting too much cooling at speed, or too much soak-back when stopped. Regardless, it reads 60F at 40 mph, and creeps up to almost 70F at a red light. Since I know it was nowhere near 70F this morning, I am guessing it's radiator/engine soak-back. So I'll probably move it somewhere into the fenderwell area.

I think it's usually placed under the front bumper so it gets fresh air, but no direct flow. You could Google "gentex rear view mirror installation" if you want to see how the thermometer is placed for some OEM rear mirrors.

[4Runner4Leon]

Originally Posted by marcus clarkus

I think it's usually placed under the front bumper so it gets fresh air, but no direct flow. You could Google "gentex rear view mirror installation" if you want to see how the thermometer is placed for some OEM rear mirrors.

Thanks, I'll have to research that. I played around today with a thermometer, and it turns out that with an ambient temp of about 65F, the entire area under the truck was close to 70F at rest. So there is a "cloud" of heat all around the front, even in the fenderwell. So I need to get smarter on how temp probes should be mounted to avoid engine soakback.

[Wedgy]

Very nice and clean looking ! Thanks for the write up.

PS , I used a piece of tinted goggle lens as a face plate, not as nice as yours but it works.

[Tyler James Inc]

Some factory temp probes are behind the front bumper, as well as in the cowl area.