cooling fan indicator ?

[bonnieclyde100]

i have recently added the od efan control on my tbi and i was wondering if there was a way on tunerpro to see when it comes on and goes off ?

[Six_Shooter]

You would need to add another subroutine to report it to the datastream, which would also require modification to the datastream, where you may have to give something up in order to get that info, though I believe there are some unused bits in the data stream that could be used.

[bonnieclyde100]

i think that is quite above my skill level right now. maybe someday i will be able to do that. the reason i ask is because im not sure my fan is ever shutting off onces it turns on. when i get to the gate at work it comes on but im not sure it shuts off when i get back up to speed.

You would need to add another subroutine to report it to the datastream, which would also require modification to the datastream, where you may have to give something up in order to get that info, though I believe there are some unused bits in the data stream that could be used.

[steveo]

attach a 12v light or LED to your actual fan relay output and hanging it somewhere you can see it?

[bonnieclyde100]

good idea i will do that. thanks

attach a 12v light or LED to your actual fan relay output and hanging it somewhere you can see it?

[Six_Shooter]

attach a 12v light or LED to your actual fan relay output and hanging it somewhere you can see it?

If all you want to know is whether the relay is triggered or not, as you suggest, then I agree with steveo, the only thing I don't agree with is where to attach it. With it attached to the output side of the relay, it will indicate that the fan is on, when it is not. When the vehicle is moving forward, air flow through the rad will cause the fan to spin, this in turn will create a voltage that will turn the LED on.

You would be best to attach it to the trigger side of the relay, because what you really want to know is whether the new subroutine is working as it should. Be mindful of polarities, and current levels. If you use a common 3V LED you will need to install a resistor inline with it, on either wire, in order to not blow the LED. Generally a 1K ohm resistor works well in applications like this. I have used as low as 690 ohms, to have a really bright LED, but that's getting close to being too much current.

[bonnieclyde100]

oriellys has some led that are set up for 12 volts to be used in dash boards. im using some for blinkers and warning lights in my dash .they work great and use little power.

If all you want to know is whether the relay is triggered or not, as you suggest, then I agree with steveo, the only thing I don't agree with is where to attach it. With it attached to the output side of the relay, it will indicate that the fan is on, when it is not. When the vehicle is moving forward, air flow through the rad will cause the fan to spin, this in turn will create a voltage that will turn the LED on.

You would be best to attach it to the trigger side of the relay, because what you really want to know is whether the new subroutine is working as it should. Be mindful of polarities, and current levels. If you use a common 3V LED you will need to install a resistor inline with it, on either wire, in order to not blow the LED. Generally a 1K ohm resistor works well in applications like this. I have used as low as 690 ohms, to have a really bright LED, but that's getting close to being too much current.

[steveo]

If all you want to know is whether the relay is triggered or not, as you suggest, then I agree with steveo, the only thing I don't agree with is where to attach it. With it attached to the output side of the relay, it will indicate that the fan is on, when it is not. When the vehicle is moving forward, air flow through the rad will cause the fan to spin, this in turn will create a voltage that will turn the LED on.

ah, good point, the cars i work with would never have enough airflow to get more than a couple volts out of an unpowered fan. trigger side would be a better idea for sure.

[Six_Shooter]

You'd be surprised just how little air flow it takes. ;)

[billygraves]

You will need to bit pack a "WORD" or byte. Then edit the Calibration to use byte xx to point to the RAM Address you have formed with your FAN On bits. Or you can use this suggestion which I did on my NON-ECM controlled Vehicles at the time.

I use a Twin color LED. I use a 470 ohm resistor on each side of the LED. (That's what these require and can handle) I connect the Red or one color to the Primary side of the relay where the ECM/PCM grounds the circuit. The other color or Green, to the Output side/Terminal of the relay.
I built this in my race car in 1988 for my electrical controls of everything and never had to find or use a test light or volt meter for any electrical problems.
When the circuit is powered up and the relay is OFF. The LED will be the RED color. When the ECM/PCM Grounds the Primary side of the relay, the RED LED will go OFF and if the contacts close to power up the fan the LED will turn GREEN.
Why such a electrical system? I wanted to know if and when each component was ON. The switches on the panel were only controlling the Ground side of each relay. The Bulk of the wire and all the current was outside the drivers compartment. I had 12 switches and twin colored LEDs.

If you are going down the road in your Crew Cab Dually with twin fans and these LEDs, the LEDs will turn ORANGE and the faster you tow your race car, the brighter the ORANGE LED. (The relay must be off for this color)

Why does it glow Orange with a RED and GREEN LED? The GM Fan motors become a generator and the LEDs enegrgizes both RED and GREEN. I have this in my Crew Cab and Sunbird 3.1L with Twin fans.