- Joined
- February 9, 1999
- Messages
- 12,050
- Reaction score
- 131
- City, State
- Vail, Arizona
- Year, Model & Trim Level
- 1992 XLT 4x4
Can anyone think of a 12v power source that is active ONLY when the truck is running.
I have a 12V aux fan for the tranny cooler.. I have it set to only run when the key is in the on position and when the torque converter is not locked. Once locked it will wait 5 seconds before turning on the fan.
The problem is.. When I turn the key to start the truck, the aux fan starts (since the converter hasn't been locked yet, it doesn't wait 5 seconds before starting).. The fan pulls 8 amps (12 amps at startup). With one fan its not too bad.. But I'm going to install another aux fan (one on each tranny cooler) and 16 amp draw while I'm trying to start the truck just doesn't sound like a good idea (and thats a 24 amp peak draw at fan startup)..
I want to change my 12v switched power to a 12v source that is on only when the truck is running, not just when the key is in the on position...
~Mark
p.s. I know someone will ask how I keep the fan from starting right away.. I'm using a 38,000 microfarad (MFD) capacitor to keep the n/o relay energized.. This means once the converter is locked it energizes the relay (and cap).. When the converter unlocks the relay is now powered by the capacitor which keep it closed for about 5 seconds (until the voltage drops to 3 volts)..
I have a 12V aux fan for the tranny cooler.. I have it set to only run when the key is in the on position and when the torque converter is not locked. Once locked it will wait 5 seconds before turning on the fan.
The problem is.. When I turn the key to start the truck, the aux fan starts (since the converter hasn't been locked yet, it doesn't wait 5 seconds before starting).. The fan pulls 8 amps (12 amps at startup). With one fan its not too bad.. But I'm going to install another aux fan (one on each tranny cooler) and 16 amp draw while I'm trying to start the truck just doesn't sound like a good idea (and thats a 24 amp peak draw at fan startup)..
I want to change my 12v switched power to a 12v source that is on only when the truck is running, not just when the key is in the on position...
~Mark
p.s. I know someone will ask how I keep the fan from starting right away.. I'm using a 38,000 microfarad (MFD) capacitor to keep the n/o relay energized.. This means once the converter is locked it energizes the relay (and cap).. When the converter unlocks the relay is now powered by the capacitor which keep it closed for about 5 seconds (until the voltage drops to 3 volts)..