Electric Cooling Fan Conversion

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kennythewelder

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Why aren't more of you using the PCM to control the fan? You can have a hysteris with the PCM, choose your own on/off, have it turn off at speed, and have it turn back on at speed if you're overheating. It can run based off of AC pressure, and can control duals in either a series parallel configuration for hi/low speeds or just on/off.
None of the GMT 400s ECMs have that ability. You would have to have done the 411 swap to do that, or so I have been told.
 

Supercharged111

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My dually, with the older style blackbox, came with an auxiliary pusher fan. I'm pretty sure the TBI trucks had this as an option on the heavy duties, and I know the 7747 TBI ECM can be configured to run an electric fan. I'll see if I can snag a screenshot of my 98-00 blackbox software, but I'm pretty sure I remember seeing electric fan control in there as well.
 

454cid

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My dually, with the older style blackbox, came with an auxiliary pusher fan. I'm pretty sure the TBI trucks had this as an option on the heavy duties, and I know the 7747 TBI ECM can be configured to run an electric fan. I'll see if I can snag a screenshot of my 98-00 blackbox software, but I'm pretty sure I remember seeing electric fan control in there as well.

I think that fan is set to come on at 225F.
 

kennythewelder

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My dually, with the older style blackbox, came with an auxiliary pusher fan. I'm pretty sure the TBI trucks had this as an option on the heavy duties, and I know the 7747 TBI ECM can be configured to run an electric fan. I'll see if I can snag a screenshot of my 98-00 blackbox software, but I'm pretty sure I remember seeing electric fan control in there as well.
Yes your rite on the 3500, and maybe even 2500 trucks, but there is no e fan on a 1500 at all. I know there was a different or up graded ECM in the 98 trucks, but 97 back has less options on the ECM. Not to mention a lot of people do not have access to a way to reprogram there e ECM, so it cost IDK $300 or so to have the ECM reprogrammed. It cost less than $50 for an adaptor and a sensor. I know in my case it was about $30 for the sensor, and maybe $10 for a new thremostat housing that I welded a nipple on for feee. So $40 VS $300 is a no brainer for me.
 
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L31MaxExpress

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Yes your rite on the 3500, and maybe even 2500 trucks, but there is no e fan on a 1500 at all. I know there was a different or up graded ECM in the 98 trucks, but 97 back has less options on the ECM. Not to mention a lot of people do not have axcess to a way to reprogram there e ECM, so it cost IDK $300 or so to have the ECM reprogrammed. It cost less than $50 for an adaptor and a sensor. I know in my case it was about $30 for the sensor, and maybe $10 for a new thremostat housing that I welded a nipple on for feee. So $40 VS $300 is a no brainer for me.

96+ blackbox all have the ability to use a single fan. My 1999 Tahoe LT came with a condenser pusher fan from GM.
 

kennythewelder

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96+ blackbox all have the ability to use a single fan. My 1999 Tahoe LT came with a condenser pusher fan from GM.
Yes I know, a Tahoe, a Burb, maybe even a van, all have pusher fans, but regular 1500 trucks do not. Point is, to use this on a 1500 truck, there is no place to just tie into. There is nothing there. At best, you will need a reprogram for the ECM. Not to mention you will need to figure out where to tie into the ECM wireing. Not a silmpe install.
 
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ericinga

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I installed a condenser pusher fan last weekend. Used a 4 prong relay and connected the switched power line to the AC compressor clutch positive lead. Works great.

Sent from my SM-G950U using Tapatalk
 

kennythewelder

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I installed a condenser pusher fan last weekend. Used a 4 prong relay and connected the switched power line to the AC compressor clutch positive lead. Works great.

Sent from my SM-G950U using Tapatalk
In my write up on electric fan swap on the cheap, (that is linked in this thread) I did the same thing. Like you, mine works grate too. Its been on my truck for several months now with no issues.
 
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