I mentioned the 08/09 because you must buy the oil cooler and trans cooler lines made for the 08/09 H2 when you want to convert an 03-07 to electric fans. The 08/09 models came with electric fans and the oil and trans cooler lines are shaped different in order to clear the shroud on the electric fans. No you do not need a new radiator. Nor do you need EFILive (that is over $600 by itself. Converting to electric fans properly is not a simple thing to do. It requires planning, having all of the correct parts, and either your own expensive tuning device (EFILive or HP Tuners) or know someone with one of those that can enable the fans in the PCM.

BCM (actually TBCM - truck body control module), PCM (powertrain control module), ECU (engine control unit - just another name for PCM). They are just terms for some of the various computers that vehicles have which control various vehicle functions. On a GM gasoline suv for 03-07 the PCM controls both the engine, transmission, fans, security but it does so in conjunction with the BCM and other computer modules. On a GM diesel with an allison transmission, the transmission has its own computer, etc.

This is all really too much for me to explain when it has all been explained thousands of times already online. Trying to type it all out when it has been done so many times before is trying to recreate the wheel. You need to do a lot of reading up online on various sites to learn about all of this. Much of it is getting fairly advanced. I'm not a mechanic. I do graphics work. I learned all of this reading online...



Also EFILive which is the other very popular tuning hardware/software. Most places who do performance dyno tuning also will likely have one or the other and could enable fans.

If someone does want to convert to electric fans, go ahead and get the tuning part does FIRST. It will not hurt anything for them to be enabled in your PCM but driving without them enabled but installed likely would be problematic unless it is freezing out.

Also - I just ordered this relay module from Amazon. Will let you all know how it works....
The last picture shows that it works with a single momentary push button and would be a work around to use the factory button. I've also had one of the factory buttons apart to try and see if there was a viable way to make it a latching button and I did not see any way that would work well.

 

How long does it take to turn on the electric fan through hp tuners?
Where are you located?

 

ok thanks, I have looked up the PCM, BCM & ECU definitions online before. For me, some of the explanations were a bit confusing. I only asked you because of how well and simple you explained everything previously in a very digestible layman terms manner. Not many experts are good at breaking things down to very basic levels like you did. I really appreciate that.

I definitely look forward to seeing how that latching really works. I will hold off on modifying (or drilling a hole, lol!) into the current factory switch until I hear back from you on how this relay works. The only concern I have about that relay is that it doesn't have a cover. Where will you mount it? Will you make your own cover?

 

It takes 5 mins to tune. I'm in upstate NY.

 

I'll mount that one under the dash behind the button and just use it to trigger a heavier duty relay under the hood.... Once tested, connected, etc I'll probably enclose it in some sort of small plastic box (ventilated) and then attach that somewhere so it does not rattle or anything.

 

Why 2 relays? Also, are you running H.I.D. or L.E.D. lights on your h2? I have H.I.Ds. but I'm thinking about switching over to all 6000k LEDs so that my headlights, foglights and hella offroad lights match in color precisely. My only hesitation is that I've read HIDs throw light further, which is better for when I'm hitting the trails.. What are your thoughts on this?

 

Two relays because the one on that little board is not very high amperage and it will be a much lighter load on it if it just has to power a larger relay under the hood.

I have LED headlights on mine. Love them but I do love quality HID headlights as well. For decent HID headlights it just about means building your own with parts from somewhere like the Retrofit Source and not using the cheapest ballasts and bulbs, using proper top quality projectors, etc. I prefer 5000k for lighting as it provides more light that is useful for human eyes and is also easier on your eyes than the whiter 6000k. That being said the LED headlights in my H2 are 6000k but so are the Hella Rallye 4000X driving lights I have on it and the fog lights so it all matches. Not as easy to find LED lights in the 4500 to 5500k color temps....

Some of the modern top quality LED headlights are really just about as good if not better for throw than HID in my opinion. I have both in different vehicles and the LED lights in my H2 seem to have just as good of a throw as the custom retrofitted Mini H1 (7.0) HID ones in my GMC.

 

Ok, got it. Please let me know how the latching relay with bigger relay works out as soon as you hook it all up. I'm going to wait drilling into that switch until I hear back from you on whether you were able to get the factor foglight switch up and running. Ironically, my 55w HIDs just went out today. I've had them for about 4 years. Can you send me a link to the exact LED lights you used for your headlights and fogs? Have they been really reliable. Do you have any pics with them all on? I want the 6000K color temp to match perfectly. I also have the Hella 500ff on my brush guard. I was going to convert them to HIDs, but now I'm thinking about switching to either the the Hella Rallye 4000 or the Hella 7 inch Valuefit LEDs. I'm just concerned about the depth of the newer Hellas and whether they will fit flush with my brushguard.

As far as the HIDs, I'm just tired of the reliability issues. I bought expensive ballasts and bulbs, but they still have gone out inexplicably from time to time and then just come back on unexpectedly days later. I'm told the HIDs are just not as reliable as the LED plug and play. If I'm out in the middle of nowhere and my HIDs go out, I'm screwed. The LEDs are just more reliable.

 

Both are in some of the photos I posted on the first couple of pages of this thread along with the exact fogs I got..... The headlights are a somewhat obscure Chinese brand Foshan Tuff Plus (they make OEM lights) Round 7 Inch LED Replacement Headlight | Vehicle Lighting | Tuffplus The A0101 is what I have. They are hard to find and there are a LOT of copycat (Forshan has a patent on the design but Chinese copy everything anyways) ones that look near identical. The box and packing is usually a good way to tell if they are the real ones or not. Superbrightleds and a couple of other companies were for a while the exclusive dealers for them in the US but I'm not sure anymore as I got them a few years ago.

 

Oh, you replaced the entire light, housing an all. I'm just trying to change to an LED bulb to fit in the OEM housing....like these:
I just don't know who the reputable LED bulb brands are.