When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have a 2002, F150 FX4 lariat, that has an electrical problem, and I hate them! I had a major drain, and figured out that it was the alternator, and put a new one on. I still have a slight drain, of .46 amps, and it should be down around .03 - .05.... I have narrowed it down to fuse number 15, in the inside fuse block, but can’t find any wiring diagram with that fuse on it. Does anybody have a diagram that might have that fuse on it? The manual says it’s for the stop lamp switch, ( speed control brake shift interlock), GEM, Rear Anti-lock Brake System ( RABS) module.
Since this thread is several days old, let me post another battery related question (no thread hijacking intended). I have electrical fans. Temperature is about 100 in Texas summer, and I would like to keep the fan on for 10 minutes after engine is turned off (instead of current engine off = fan off). 15A x 10 min = 2.5 AH. Google search shows a typical car battery has about 100 AH. So 2.5 AH drain from 100 AH reserve is no big deal, right?
I don't have the formula in front of me, but off the top of my head, you will be lucky to crank your truck if you did that.
It is something like inductive reaction - Xl with XL=2piefl
or
Power (watts) = E x I x power factor. The true power in a circuit is found by multiplying the product of the voltage and the current by the power factor.
You have to understand Kirchhoff's law to get the true reading of how much you will lose or for how long. (I think I spelled his name right: I hope, but you can look it up)
So basically you are running a parallel circuit though the fans and back to the battery. You need to know what the Milly amps are of draw/volts and how long, plus resistance.
The sum of all voltage drop equals the source voltage. total resistance = load/time/ amps
mind you this is off the top of my head. R = E / I = what you want to know. Where Power/volts = I x E = how long
I know I just messed up your mind, but I would need to know what is the amps pulled and all of that to give you a direct answer. If you have the name brand and all I can look up the info and get back to you after looking at their product information. Also need to know how you hooked this up to your truck on which circuit.
Sorry I could not give you a better answer.
I am not electrically educated or trained, and will gladly accept your offer for sanity check.
The fans were removed from a Cadillac Eldorado. Year I don't remember. But I measured current draw with a clamp-on ammeter. 14A for both fans (8 and 6 amp each). The fans were installed in Florida and survived 2 summers there. Once I left the fans on for testing and they ran 5 minutes until temperature sensors cut them off. Now I am in Texas and find Texas summer is more brutal. I need to adjust the fan operation.
For wiring I tapped directly from the battery with an inline fuse. Each fan has a separate fuse (15A) and a relay (Ford OEM). Both fans are turned on/off at the same time. If you need additional info, please let me know. Thank you for your help. Fuse box location, 50A inline fuse Fans and relays
The next question I have is why would you want them to run after turning off your truck?
The thermostat opens and closes to help cool your truck and you don't gain anything by just running the fans after. Your truck engine will still heat up back to where it was when you crank up your truck.
From what I have seen you will see the battery not crank your truck after 3-5 minutes because the amp draw of both fans, plus other things will draw down the battery. You have to remember that even if a truck or car is setting still not running that there is a power draw also that has to be added too.
A simple way to check this is for you to run a direct line to the fans and(make sure you have a way to jump off your battery before doing this) turn them on for the amount of time you want them to stay on and see what happens.
Not a fix but until I find a problem I install a battery cutoff switch on the ground side so I don't drain batteries (and usually leave them in place for maintenance convenience).
The next question I have is why would you want them to run after turning off your truck?
The thermostat opens and closes to help cool your truck and you don't gain anything by just running the fans after. Your truck engine will still heat up back to where it was when you crank up your truck.
From what I have seen you will see the battery not crank your truck after 3-5 minutes because the amp draw of both fans, plus other things will draw down the battery. You have to remember that even if a truck or car is setting still not running that there is a power draw also that has to be added too.
A simple way to check this is for you to run a direct line to the fans and(make sure you have a way to jump off your battery before doing this) turn them on for the amount of time you want them to stay on and see what happens.
Battery voltage initially 12.76 V, after 10 minutes of fan running, 12.68 V. So it is doable. Now I need to select a delayed off switch/relay. Why do I want to do this? Just a few minutes of fan can quickly cool the hot AC refrigerant to air temperature.
Battery cutoff switch is a good idea. I was going to get one anyhow. Thank you for the reminder.
AC refrigerant in the condenser will swiftly cool to ambient though given the other system restrictions that's not likely to affect the rest of the system as the pump blocks recirculation. AC doesn't thermo-syphon like a T Model Ford cooling system which does continue to circulate until coolant reaches ambient temp with engine off. If ya don't already have a handheld IR thermometer they're fun to play with when doing auto HVAC work and worth owning since what is not measured is not known.
I am not concerned about a specific part. Prolonged exposure to high temperature does not help. Rubbers, plastics, battery, all will have less trouble. At least theoretically.
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
