Thinking about cooling fan indicator light. Need help.

[YeahPete]

I have never done anything related to electronics, but this LED will put my mind at ease for when I install my grill block.

So what I need is help... I am quite savy at figuring things out but I've never worked with electronics before so... yeah.

What I want is a little LED on my dash to turn on when my cooling fan kicks on.

Questions so far:
I have a scanguage, do I even need a fan LED?
What temps should I be watching on my scanguage? (2 different temps)
What tools will I need?
Would any soldering be needed?
What guage wire and what size LED?

Not sure how to go about figuring out what I need. Much thanks to those with input.

[MetroMPG]

Quick search shows a number of people here have done this. Have you searched/read any of these?

http://ecomodder.com/forum/showthrea...ing-19112.html

http://ecomodder.com/forum/showthrea...ions-8434.html

http://ecomodder.com/forum/showthrea...fan-15287.html

EDIT: added....

I have a scanguage, do I even need a fan LED?

The SG doesn't show how often the fan is coming on. It will only show your current and max. temps (FWT -- Farenheit Water Temp is the gauge label).

So it can only tell you whether or not it came on at least one time - if you know the preset temp at which your fan will kick on, and your Max FWT exceeded that on the current trip.

[Slow_s10]

I can't answer your Scangauge questions but If I were doing a project like this personally I would be soldering and heat shrinking everything. However there are definitely other ways to get it done. In any case the easiest way would be to get an Led that is already prewired and setup for automotive voltage. You can get these prewired LEDs fairly cheap. For example I did a quick search on Amazon and you can get a 10pk of prewired leds for automotive use for like $6 (Qty 10- LED Lights- 3mm pre wired 12 volt leds- 12V Red : Amazon.com : Automotive). Then all you would need to do is use some fairly small gauge wire 18~22 and either run both positive and negative from the LED or just the positive to the E-fan. Then just splice the wires from the LED right into the efan wires. Positive to positive negative to negative, or if you only ran a positive wire to the fan, then just ground the LED negative wire somewhere under the dash. This is usually where I would solder in the wire from the LED but you can also just use something like a 3M T-Tap, which can just be crimped onto the Stock E-Fan wire and then you can use a normal spade connector to connect the LED wire.

The hardest part of the whole thing will probably just be getting the wires from the engine compartment to the interior of the car cleanly. I can't speak for your paticular car but usually the easiset way is to use an existing gromet and just go through there. but if it becomes necessary to make your own hole for the wires make sure you get a small rubber grommet to protect the wires.

[Cobb]

I can tell by my sg2 when I see a sudden 20 degree drop from the temp the fan is suppose to come on.

On another car I used a prewired 12 volt led from an online store. I loosely hooked it in parallel using its leads to the original connector and ran it up to the edge of the hood and windshield wipers so I can see it from the drivers seat.

[Slow_s10]

That definitely works too, and it simplifies the issue of having to run wires through the firewall.

[YeahPete]

Thanks for all the info so far.
I'll be looking into the matter. I need to acquire a few tools as well.

[YeahPete]

Welp, I looked into it a bit more. I have only 1 fan. I think it is always on. I will verify this next time I start my car.

[Daox]

It should not be running continuously.

[gone-ot]

Just a "Wild Donkey Guess" but sometimes one fan terminal (HIGH-side) is wired directly to +12VDC and the other terminal (LOW or GND-side) goes to the "switching-to-ground" circuitry, either a grounding thermal switch or electronic-control from the engine ECU/ECM that provides the electrical path to ground. Hence, if he has connected to the "high-side" terminal, it would appear that the fan is ON all the time.

[YeahPete]

OK. I Checked the fan yesterday. It is not always on. I also kept an eye on the water temp via scanguage. Warmed up to 190 F on acceleration. When coasting temp went down to 186 F.