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Pull fuse out make sure the fuse holder itself has not melted within. Also make sure ground wire is snug and at a good location. I see a footnote on G Speed website that make sure the Fan ECU has not been altered. Temps can be adjusted. - Who knows with the full tilt all the time in old adjustment it is not allowing this thing to work.
Pull fuse out make sure the fuse holder itself has not melted within. Also make sure ground wire is snug and at a good location. I see a footnote on G Speed website that make sure the Fan ECU has not been altered. Temps can be adjusted. - Who knows with the full tilt all the time in old adjustment it is not allowing this thing to work.
ground and fuse are good not 100% of th fans tuning history
This Dewitts type of brushless Spal fan is designed for the aftermarket. It uses a positive logic duty cycle. The stock Spal fans designed for GM use a negative logic duty cycle. Almost all the builders buy these GM brushless fans from C7 Corvettes, Zl1 Camaros or even the Chevrolet Volt. Your C6 Corvette is set in the tune to PWM electric 128hz. The stock C6 Corvette fan was a brushed Seimens fan that used a negative logic. Ideally the settings should be changed 100hz but many builders have left the setting alone at 128hz. Even the Spal engineers report it works at 128hz but the optimal setting is 100hz. G Speed doesn't sell this Dewitts fan assembly currently. It looks like they now sell the OEM C7 Corvette fan. It can be wired up to be controlled by the stock E38 ecm. The Dewitts fan assembly was sold with the understanding that it had to be wired with a special SPAL coolant sensor that had the ability to put out this positive logic signal. These sensors have/had a very short life (reliability) problem from what I have read.
There is a company (Widget Man) that sells a small device (model PCAv00) that can be used to convert this positive logic to a required negative logic. It is a 4 wire hook up. Positive 12 volts from ignition source, ground wire, PWM signal from ecm and finally the pwm signal to the fan. This device is very small and sells for about $53. It can be purchased from the company or on E Bay. With this device installed you shouldn't need to change the tune settings with HP Tuners or EFILive.
The only other alternative is to purchase a standalone PWM module from the Widget Man or Lingenfelter and wire in a separate coolant sensor. I don't recommend this however because you lose the ability for the ECM to control the fan operation.
This Dewitts type of brushless Spal fan is designed for the aftermarket. It uses a positive logic duty cycle. The stock Spal fans designed for GM use a negative logic duty cycle. Almost all the builders buy these GM brushless fans from C7 Corvettes, Zl1 Camaros or even the Chevrolet Volt. Your C6 Corvette is set in the tune to PWM electric 128hz. The stock C6 Corvette fan was a brushed Seimens fan that used a negative logic. Ideally the settings should be changed 100hz but many builders have left the setting alone at 128hz. Even the Spal engineers report it works at 128hz but the optimal setting is 100hz. G Speed doesn't sell this Dewitts fan assembly currently. It looks like they now sell the OEM C7 Corvette fan. It can be wired up to be controlled by the stock E38 ecm. The Dewitts fan assembly was sold with the understanding that it had to be wired with a special SPAL coolant sensor that had the ability to put out this positive logic signal. These sensors have/had a very short life (reliability) problem from what I have read.
There is a company (Widget Man) that sells a small device (model PCAv00) that can be used to convert this positive logic to a required negative logic. It is a 4 wire hook up. Positive 12 volts from ignition source, ground wire, PWM signal from ecm and finally the pwm signal to the fan. This device is very small and sells for about $53. It can be purchased from the company or on E Bay. With this device installed you shouldn't need to change the tune settings with HP Tuners or EFILive.
The only other alternative is to purchase a standalone PWM module from the Widget Man or Lingenfelter and wire in a separate coolant sensor. I don't recommend this however because you lose the ability for the ECM to control the fan operation.
I found the widget man module so fingers crossed it will work
Aftermarket fuel injection engine management systems have the ability in their settings to control all types of Spal fans (for example Holley Terminator). A factory GM ecm can only control a GM Spal fan. Hope this makes sense. The Widget Man PCAv00 device is fairly new to the market. It was designed to help the aftermarket with this mismatch. It can correct the pwm signal mismatch with electric fans and coolant pumps.
The factory GM Spal fans are much cheaper to purchase over the aftermarket equivalent versions. If one is purchased from wrecker then the pricer is even better.
Reach out to the Widget Man before you purchase( I understand he is very helpful). Explain what you have and confirm that this module is what you need.
Aftermarket fuel injection engine management systems have the ability in their settings to control all types of Spal fans (for example Holley Terminator). A factory GM ecm can only control a GM Spal fan. Hope this makes sense. The Widget Man PCAv00 device is fairly new to the market. It was designed to help the aftermarket with this mismatch. It can correct the pwm signal mismatch with electric fans and coolant pumps.
The factory GM Spal fans are much cheaper to purchase over the aftermarket equivalent versions. If one is purchased from wrecker then the pricer is even better.
Looks like the Widget Man may have a solution. He has a few other neat items for sale too. I think if it does not work out you can always go back to the OEM set up as it looks like the wiring is there to convert back. The C7 G Speed fan is a better fan (than C6 OEM) so do your best to see if you can get it to work.
I MAY HAVE MADE A MISTAKE! I just realized I was looking at a picture of double06's radiator fan assembly. His is a Dewitts fan assembly. I Just caught a brief glimpse of Paulmg1986's fan assembly (at the bottom of post #12) and realized his is actually a C7 fan assembly. It is a GM fan so it doesn't require the widget. Can you cancel the order as it isn't needed?
The issue now is the fact the previous owner claimed the previous fan ran all the time. Did someone modify the tune to accomplish this? If so then the tune needs the coolant fan run values put back to stock. You will definitely need someone with HP Tuners or EFI live to accomplish this.
Perhaps the previous owner omitted the original controller and just hooked it up with a ignition source and a relay so the fan would come on when the car is running.
You really need to find where the dark green wire is coming from. That should be the stock PWM signal wire from the ECM.
The dark green wire connects to the small gauge wire of the C7 fan assembly. The large gauge red wire of the C7 fan assembly attaches to the original large gauge black wire that supplied power to the original controller. The large gauge black wire of the C7 fan assembly connects to the large gauge black wire that connected to the original controller.
The dark green wire connects to the small gauge wire of the C7 fan assembly. The large gauge red wire of the C7 fan assembly attaches to the original large gauge black wire that supplied power to the original controller. The large gauge black wire of the C7 fan assembly connects to the large gauge black wire that connected to the original controller.
the green signal wire was connected to the green wire from the plug, to my knowledge these fans have never run, the old fan were hard wired bypassing the pwm I believe
the green signal wire was connected to the green wire from the plug, to my knowledge these fans have never run, the old fan were hard wired bypassing the pwm I believe
if the widget doesn’t work I may just go standalone speed controller or try the tune last ditch would be to go back to stock
the green signal wire was connected to the green wire from the plug, to my knowledge these fans have never run, the old fan were hard wired bypassing the pwm I believe
When you bought the car was this C7 fan assembly installed already? Or did you install it?
If the dark green wire is good all the way back to the ECM and you have the tuner return the fan settings to stock and it still doesn't turn on then your pwm circuit internally in the ECM is defective. This means you will need a replacement ECM. They are relatively cheap because they were also used in many other GM vehicles. You can purchase them on E Bay with a complete stock tune for about $140. The stock tune/program from GM is loaded into the ECM based on the VIN from your car. When you buy it on E Bay....they will ask for the VIN number.
The ECM for your 2007 C6 Corvette is #12597121. They were used on 2006 and 2007 Corvettes and many GM trucks in 2007. Here is a picture of the backside of the ECM. My finger in the picture is pointing to the service number.
The ECM for your 2007 C6 Corvette is #12597121. They were used on 2006 and 2007 Corvettes and many GM trucks in 2007. Here is a picture of the backside of the ECM. My finger in the picture is pointing to the service number.
awesome thanks for the info would I need a specific scan tool to get everything programmed ?
