Electric Fans Auto/Manual switch
I'm currently in the process of wiring up my electric fans with an auto/manual switch. Currently the fans are operated two ways. One when the A/C clutch engages and two when the trucks water temp gets about 190. They even run when the truck is off. They are not supposed to but I'm about to fix that when I wire in the switch. When the switch is in the auto position, the A/C clutch controls the fans along with the temperature sensor. In the manual position the fans will run constantly. This gives me better control over my fans.
Throttle Position Activated Switch
I will do my best to explain what the circuit does. Then I will then explain the problems I am having. If you know of someone who might be of more assistance feel free to pass this along. I am in desperate need of some help.
What I am trying to design is a Throttle Position Activated Switch. As you currently know the TPS on our trucks send a voltage signal to PCM. The box reads that signal and compares it to set point. If the input voltage is greater then or equal to the set point the output comes on. I am trying to get this output to drive a relay for my secondary pump.
Relay needs 12v-14v and 150mA or greater in order to operate. NTE922 or LM308 do not output enough amps to operate the relay. Tried to use a transistor but cant get it to operate properly. Need the NTE922 or LM308 to operate the transistor in order to output the volts with enough amps to operate the relay.
The LM308 is a voltage follower designed to separate the Output On LED from the Output of the NTE922 Pin 7. If not then the Output On LED pulls too much voltage from Pin 7 and the Output voltage is too low. Pictures of the circuit are from a program that just lets me draw circuits. They are not actual representation of what I have built.
1. Didnt work, not enough amps to operate relay.
2. Didnt work, when 12 volts applied to Collector of transistor, Emitter sends 12 volts out regardless of Base voltage. Base should control the contact of Collector to Emitter.
Here is the zip file the includes the documentation and all the pictures if you want to download them to show someone who might be able to help.