Aftermarket Digital Temp Gauge Step By Step

[Evan G]

i was sick of my 4k showing 3/4 temp and scared its gonna overheat/ blow a head gasket. so i went down to my nearest autobahn and found this autotechnica digital temp gauge for the price of $49.99

 

please always go electric over mechanical, mechanical take time to show the temp so when its in the H position its oready to late and expect a blown head gasket.

 

 

The Gauge

 

3 wires.

-Black (ground) I went around a bolt in the steering column

-Red (Power) Around the Wiper fuse, so the gauge turns on when keys in the "ACC" position

-Green (Sender) To the temp sensor

 

The Sensor

 

the Coolant temp Sensor for the gauge was 10mm in diameter. the original temp sensor and the emission valve was about 1/2 inch in diameter. so a simple remove old and fit new wasn't gonna work.

 

Modification

 

(difference between the ke70 emissions sensor and a ke55 is that the ke70 sensor has a 4mm hole going though it and was easier to drill)

i removed the emission sensor

drilled it with a 10mm drill bit (its got a small hole going straight through it so you can use it as a pilot hole)

tap it with same thread pitch

applied some plumbers tape

tightened it into the emission sensor

and installed into thermosat housing

 

Please Run a New Sensor Wire because the 30 year old wire has probably frayed/ high resistance therefor giving you a false reading!

 

Other Pics

 

Close up of the modified sensor

 

Original Temp Sensor

 

Oil Pressure Sensor

 

Cable tied :thumbsup:

 

Any more Question Please Pm ME

 

Worth A Sticky Admins?

[Evan G]

went for a small drive around the block, sat on 76 degrees and 79 with the a/c on (ambient temp around 25 ish?)

 

76 degrees and the toyota gauge was showing half way?????

 

ill monitor the progress and let you guys know how it all goes

 

BEST $49.99 SPENT!

[Dann_m]

Thanks man, MODS STICKY NOW! it's pro. i'll so be able to set up my gauges tomoro tanked as haha with this diy. :thumbsup:

 

cheers man

[towe001]

Not a complaint or anything. But i'd sooner use an analog display (read as a needle display like the speedo) over a digital read out display cause in the heat of the moment remembering what the "safe" numbers are on the digital can be forgotten whereas if the analog is set with the needle pointing up at its "safe" position and a glance at the gauge will quickly and easily show any problems.

The same can be said for the oil pressure sender - run a T-piece so that both pressure senders can be used. One for the gauge and the other for the light. The oil pressure light can catch the eye a lot quicker then the glance at the gauge when remembered.

 

And one of the reasons for choosing electric over mechanical is that the sensor for the temp gauge is connected to the gauge and the pressure gauges (eg - oil, fuel) needs tubing running from what ever to the gauge and needs care to be taken for kinks, splits. Whereas electric its a simple matter of running a couple of wires.

 

 

Dimmable lighting for the gauges - find out which side of the rheostat, thing for dimming the dash lights are on and splice in both wires for your gauge. More then likely will need the wiring diagram for the dash cause the ground (or negative) wires go through the rheostat. If its not done correctly the lights will either stay on , not come on or will not dim down and/or turn off when the dimmer knob is turned right down.

 

Cheap gauge cover - depending on the size of the gauge but a tow ball cover is nice and cheap. Just make up the bracket from a couple of pieces of alloy, if needed.

 

 

Good write up Evan :thumbsup:

[Dann_m]

I was able to wire up 3 gauges today with this guide in about an hour and half. Oil pressure water temp and volts. i ran a single earth line to the chassy of the car and connected all three earths to this one. aswell for the ignition 12v i ran 3 cables off the one, it was much easyer this way and less mess. they work perfectly and i now know how hot my car is! :thumbsup:

 

Thanks heaps mate good work.

[Taz_Rx]

Thanks man, MODS STICKY NOW! it's pro......

 

Couple of little things need a bit of a shimmy, then I'll chuck it in the tech articles section, we don't sticky things in these forums.

 

I'll fix the couple of things when its not after midnight on xmas day!! ;)

 

.....well technically that makes it Boxing day huh! :thumbsup:

Edited December 25, 2009 by Taz_Rx

[Evan G]

a bit of a update, 37 degree day A/C ON! and the gauge showed a max of 89 degrees problem solved

[Dann_m]

a bit of a update, 37 degree day A/C ON! and the gauge showed a max of 89 degrees problem solved

 

 

awesome, also with the water temp fittings you don't need the adaptors that come with the sensor for a ke70 not sure of other models if people were wondering what that bolt is for :)

[jackbyo]

bumping an old thread here with some more info if anyone's interested. if you'd rather a needle point display that matches the stock gauges. (as towe mentioned above. it's as fast an accurate as a digital display as well) and you don't need to modify anything

 

I picked up a 52mm VDO electric gauge which matches the stock ke3x-5x gauges perfectly.

the good thing is that it's made to go with a VDO temp sender which fits in with a little adapter - no modifications required

 

prices and part numbers are as follows

gauge - 310010014 - $44

temp sender - 320.002 - $15

and whomever you buy it from should have a tapered brass adapter to bring the 1/8th thread size of the sender to M16x1.5. cost me $7

Oh yeah and another $8 will get you a tidy little VDO bracket to fit the gauge into

 

so all up i paid less than $75 and installed it in an hour.

same wiring Evan wrote up

1. Black - ground bolt anywhere

2. Red - power from a fuse (thanks evan)

3. Blue - sender. I taped the end of the wire to a coathanger and poked it through the rubber grommet on the firewall where the main wiring loom travels. easy as

 

VDO makes good parts too... i wouldn't bother with Calibre shit from SCA as it's ugly, more expensive and made in China.

here it is, I mounted mine under my choke with 2 pre-existing bolts. I gaffed those wires outta the way after this photo :y:

 

 

 

now instead of worrying about a very old, incorrect mechanical gauge with no numbers on it, i now know that my engine is sitting just under 80 degrees in traffic on a hot day :cool:

 

 

future plans are to take apart the dash cluster and mount this gauge were the now dead stock gauge lives :y:

 

cheers