https://www.lsenginediy.com/upgrading-gen-iii-ls-series-pcm-electric-fan-guide If your engine uses an electronic throttle body, begin with a PCM and ba… - LT1 - LS1 - 05+OEM - Flex-a-Lite - Universal - Street & Strip - We have you covered. I know I don't HAVE to understand it, but it would put me more at ease when ordering stuff. That includes fans from the LS1, LT1, 350 TPI. If your project uses electric fans, begin with a PCM calibration from a vehicle that has electric fans. This makes for easy, Hassle Free hook-ups right out of the box. The Hi-fan perhaps 10* higher. Your #1 Source for OEM Operated PCM Controled and Universal Electric Fan Harnesses. This is better than just running two relays that turn the fans on individually at high speed because it is less inrush current on your electrical system. Available for most popular LS swap applications, these radiators are constructed entirely of aluminum for exceptional weight savings over stock equipment. Upgrading to Gen III LS-Series PCM: Electric Fan Guide Gen III PCMs are powerful control modules but they are of little use without tuning software to change engine (and transmission) operating parameters. The PCM would send a signal (via ground?) We are currently up … Yes (+$10.00). PSI sells Standalone Wiring Harnesses for GM Gen II, III, IV, & V LS/LT based engines and transmissions. PSI sells Standalone Wiring Harnesses for GM Gen II, III, IV, & V LS/LT based engines and transmissions. Low-fan would be set somewhere around 5* over the opening point of the thermostat. The fan control wire is fused/relayed and can connect directly to your Fan using 10 gauge wire (minimum size).". Avoid having to buy additional software programs, learning how to think in computer code, or relying on a questionable 3rd party tuner. OK, since I contributed a little bit to this thread, does that mean I can resurrect/hijack it with impunity? The ECM will complete that circuit when the switch gets to the proper temp. In GM LS applications GM used three relays to control your fans in series to enable the fans to work together. Looking for an Affordable, In Stock, Plug and Play wiring harness for your LS Swap? THANK YOU to all that stuck with us during this hectic time. And an LS swap will make all of our acceleration problems a thing of the past. to use twin fans, about 12 inches in diameter, staggered high and low. When I measure voltage at the relay I get 12v on both sides of the coil. Control is set to turn on a 12 V fan at 100 Deg C (212 Deg F) coolant temperature. Often there are Low and Hi-temp on circuits for dual fan use. The LS swap pan from Moroso features integrated baffling for oil control, an angled sump, and is a fabricated steel unit. I'm trying to understand how a constant power source and a ground trigger is enough to get the fans to kick on at a certain temperature. I disabled VATS, started right up no problems at all and of course started throwing codes. Control is set to turn on a 12 V fan at 100 Deg C (212 Deg F) coolant temperature. The fan (s) are triggered via a temperature switch and 40-amp relay combination. The fan control wire is fused/relayed and can connect directly to your Fan using 10 gauge wire (minimum size)." Also how to enable the fans in HP Tuners when using a truck harness. One of the most challenging parts of installing an LS engine is finding the correct radiator hoses. This is the new harness that many customers have been asking about. The harness is 4.5 feet long from red positive connector to the end of the fan connector. The ECM is using a relay, and energizes the relay when it detects a certain temperature. From propelling the LS-, Coyote-, and Gen 3 Hemi-swap trends, to continuously innovating late-model and vintage vehicle performance, Holley’s commitment to its customers and their cars is at the core of everything we do. LS wiring harnesses and swap kits for all Gen III and IV engines. A proper shroud allows air flow from the entire core to reach the fans. The “LS” can mean any engine made by GM from a factory truck 4.8 to GM’s popular LS3 or LS7. Select an option... Only logged in customers who have purchased this product may leave a review. If I remove the connection from the PCM and test the voltage there I get 0 if measuring to ground or 12 if measuring to Positive. No more sticking a temp bulb through the radiator. Don’t worry though, it is designed not to hang too far below the crossmember of your car. We use these to supply ground to either the fan or fan relay, … I would say it a bit differently: the ECM grounds the coil circuit in the relay (86 to 85, with 85 going to the ECM) which allows power to flow (30 to 87) to the fan motor. This task is greatly simplified, In many cases, if you’re putting MegaSquirt on a car that came with an LS motor, we recommend installing the MegaSquirt in parallel with the stock ECU if you want these features to keep operating. Flex-a-lite® now has a line of performance aluminum radiators specifically for LS engine swaps in popular muscle cars, trucks and Jeeps. Hello, New to HPTuners, but loving it. Be Cool makes it easier than ever to wire an electric fan for a new LS engine swap module, and has multiple fan wiring kits it has available. No dyno, no tuner, no factory re-flashed ECU! The specific LS engine you choose to start with will depend mostly on the budget you have to work with. 1999-2002 Silverado, Sierra, Tahoe, Suburban, and Yukon. All Be Cool LS Swap Modules contain a ''vehicle specific'' Be Cool Radiator, Shrouded Electric Fan(s), Fan Brackets with Hardware, ''Easy to Use'' Wiring Harness with 40 AMP Relay(s) and Sending Unit, Billet Recovery Tank w/Cap, and to top it off a Be Cool Signature Billet Cap. Not sure about the fan output responding to the sensor independent of the compressor output control state. The Flex-a-fit® radiators made by Flex-a-lite feature dual-pass design with the inlet and outlet on the passenger side tank. Simply hanging a fan against the back of the radiator core is not advised. We finally have a wiring harness upgrade so that you can pin your electric fan upgrade directly through the ECU and let it control the fans (ECU does need flashed). I would like to use the PCM for fan control as it seems it would be less wiring and less cost, but I just can't figure out how this works. The dual pass flow offers superior cooling capabilities by flowing the coolant twice across the radiator. Getting to the bottom of what it takes to wire your swaps fuel pump and fans. Gen V 2010-2019 Camaro Fan LT Swap PWM Fan Harness, 1999-2006 Silverado Sierra Tahoe Suburban Yukon Fan Harness for GM Fans, Gen V 2014-2018 GM Truck/SUV LT Swap PWM Fan Harness, 1999-2002 Silverado Sierra Yukon Tahoe Suburban A/C Update Kit, Gen III (24X) Stand Alone Harnesses, Kits, and PCMs, Gen IV (58x) Stand Alone Harnesses, Kits, and ECM/TCM, Gen V Stand Alone Harnesses, Kits, and ECM/TCM, Gen III DBC (24x) EV6 Injectors (Flex Fuel/Gen 4), Gen III DBC (24x) Vortec TRUCK/SUV Multec Injectors, Gen III DBW (24x) EV6 Injectors (Flex Fuel/Gen 4), Can be used in universal applications when not using a BP Automotive Harness, Weather Resistant, Factory Style Underhood System, Made In The USA at Our Facility in Kentucky. Startup guaranteed. LS engines use a … Typically, these units are used to activate a fan on an LS swap vehicle, but they could have other uses as well. The PCM is sending a ground signal to the relay but the relay is not activating. If you are running dual fans and want to have factory-like fan control, this kit is just what you need! Our first step for the swap was figuring out what LS engine to go with. From propelling the LS-, Coyote-, and Gen 3 Hemi-swap trends, to continuously innovating late-model and vintage vehicle performance, Holley’s commitment to its customers and their cars is at the core of everything we do. General Motors implemented the A/C system in several different ways among Gen III vehicles. What's the exact 2008 platform this swap came from? The GM LS and LT lines of V8 engines are perfect for engine swaps, and now, Speartech is offering a way to make the LS V8 or LT V8 swap even easier. How does the stock ground trigger fan relay for an LS work. An “LS swap” is an engine switch and installation. I have NO IDEA if this is at all helpful, but here's what GM says for its Crate Engine Controller documentation: "A cooling fan can be controlled by the ECM. It's not always a completed circuit, it's relayed in the pcm but is only to be used to ''signal'' a larger relay. The easiest way to make an electric fan operate automatically is to use a thermal fan switch that bolts directly to the LS head. Looking for an Affordable, In Stock, Plug and Play wiring harness for your LS Swap? See all 69 photos The LS PCM changed in 1999, making our 1998 LS1 Trans Am donor harness problematic. The PCM calibration is specific to each of these implementations. The FiTech 70051 Ultimate LS Standalone EFI ECU kit is the ultimate LS swap computer for DIY enthusiasts who want full control over their engine and transmission. Look at the picture to compare to your fan connector. With this kit both fans will turn on low speed together when the low-speed relay control is triggered, then when the high-speed relay control is triggered both fans … All the items listed below are things you will need to consider, research, and plan on having when doing an LS swap. In GM LS applications GM used three relays to control your fans in series to enable the fans to work together. A complete installation instruction booklet is included with every module. A short time ago, we did an article on Edel b rock’s Pro-Flo 4 EFI system. Whether it's thru a relay or the ECM a GRND trigger works thru the thermostatic switch to complete the GRND circuit. I have seen one that worked that way but that doesn't mean all do. Dec 22, 2014 - #car #fan #control #relay #kit #efi #conversion #kit http://www.psiconversion.com/tech_articles.html# In this story, we added a Comp Cams camshaft package along with a set of shaft rockers on a junkyard 5.3-liter engine and dynoed it … Champion Cooling Systems Dual Pass Radiators are a perfect choice for your LS conversion vehicle. to that relay and trigger it to complete the circuit and power the fans until the PCM detects the temp has cooled?Pretty close. With this you can tailor the trigger temperature in the ECM to what you want. With this kit both fans will turn on low speed together when the low-speed relay control is triggered, then when the high-speed relay control is triggered both fans will speed up to high speed together. Optional fan connectors can be added for a plug and play connection to 1993-2002 LT1/LS1 F-Body OEM fan assemblies. and we have a harness for 2005-12 GM Truck fans. Silverado, Tahoe, or ? Also included is an easy-to-follow wiring diagram. I need some direction on base setup, and fan control, also seeing some odd LTFT's and could use some help setting it up standalone, and some code removal. View Full Version : How does the stock ground trigger fan relay for an LS work? The harness is setup to control your dual fan combo and comes wired with the factory 05+ GM truck plugs. If given a choice I'd use the ECM/PCM commanded output. 2003-2006 Silverado, Sierra, Tahoe, Suburban, and Yukon (DBC ONLY). We wanted to see exactly how cheap we could swap an LS into an older full-size GM car for and what other items needed to be considered during the swap. Of most importance is the consideration of electric fan control. We decided to simplify it with a Painless Performance Products LS1 swap … If you have A/C you will want to confirm if the A/C command input on the ECM will turn on the fans once the compressor starts running. The pan has the capacity of seven-quarts and is six-inches deep. Motor - LS1, 04 GTO 6 speed, setup standalone in a drift car. This unit is rated to close the circuit at 190*. Trying to find a wiring diagram to look at is kinda hard without that. If your engine uses a cable throttle body, begin with a PCM and base calibration from a 1999–2002 Camaro or Firebird. We have moved! Even with 12V at the fan there is no flow without a GRND. Before getting too far into a discussion of electric fans and PCM calibrations, it … No On many LS powered cars, the factory engine control unit does a lot more than controlling the engine. Made in the USA. We also have another fan harness with no fan connectors so you can connect to Flex-a-Lite, SPAL, etc. :). I am working on a LS swap and I cannot get the cooling fans to work.