Power Draw

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FordTechOne

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My raptor was dead dead when I came out to leave from work. I jumped it and it started fine. When I looked at the display on the sct programmer, it showed the voltage to be right around 12.2 volts. When the fans kicked off, voltage went up to 13.5 to 13.8 volts. So I took it in to O'Reilly's to see if they could test the alternator. Their test showed that the voltage regulator failed. Diodes passed and sitting there with the fans on, it showed 13.4v on their test screen. From time jumped to when I got back to the house was around an hour of run time on the alternator. Voltage at the battery check to be 12.87v after shutting off.

I have a $75 multimeter from O'Reilly's. It does do milliamps. @FordTechOne Can you elaborate a little more on the draw test? I'm not clear on the "try not to break the connection when instsalling the multimeter."

Wouldn't I need to disconnect my negative terminal to measure the amp draw or are you saying to have probe one on the post and one clipped to the terminal as I unhook the cable after 45 mins? That's kind of how I take it, but any extra info would be appreciated.
First thing to do is open both front doors and move the latches to the closed position with a screwdriver. The BCM will think the doors are closed, so it won’t stay awake. Be sure to release the latches using the door handle before trying to close them after you’re done testing.

To prevent breaking the connection, clip one lead to the negative battery cable next to the terminal. Then loosen the battery cable from the battery terminal, lift it off the post slightly, and touch/clip the other lead to the battery terminal below the cable end. The cable can then be removed without breaking the connection. If you break the connection, you’ll just need to wait the 45 mins for the modules to go back to sleep.

A bad alternator can also cause a draw; you may want to disconnect it to rule it out as a potential cause.
 

nd3

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This is probably not your problem since it dies so fast but maybe will help somebody else out. My stupid overhead visor light will stay on if you leave the visor down. The mirror door flops and will hang open which leaves the vanity light on. I always have to remember to put the visors back up when I stop.
 

The Car Stereo Company

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dont forget to put a weight or tape down the hood pin when under the hood. meter needs to be set to amps also. a 3amp draw is a lot. i have found a bad bcm in the past on a couple occasions. but if your alternator isnt charging then the alternator could be the problem. whats the output of the alternator? you cant go by voltage alone, (but can make a pretty educated guess) so if you have an ammeter, that would be ideal. or like what @FordTechOne said, disconnect it to rule it out.
 

The Car Stereo Company

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As far as the ones inside the cab. Open the door and let it set for a while. When you go in to pull a fuse, just do not close it again. You can almost close it and it shouldn’t trigger then sensor again.

Pull it in the the garage and open all 4 doors and do not close them all the way after that.
this is your excuse to drink more beer. waiting with a door open...... jeez spoken like a true alcoholic...... ask me how i know...... just latch the door like what @FordTechOne said.
 
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BSouders80

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Fuse for the trailer brakes was good and no change in amp draw when removed.

Alternator is charging.

I’ll disconnect alternator tonight, try door latch and hood pin tricks and stay after it.

This morning when driving to work after charging at 2amp for 6 hrs, voltage on Sct is as reading 14.2 volts
 

WNCHSTR96

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When I first read this I thought for sure your P wasn’t showing orange in park, after reading through the comments I agree that 3 amps is high, and I would think it’s like a ground fault some where.
 
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BSouders80

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I've not been able to get back to trouble shooting. I believe the next thing that I will try is disconnecting the alternator power cable to see if that is drawing any power.

Good grief, if that thing is bad. The alternator that I picked up was $340 + the install. I wish I had known that the SC had to be taken off if an alternator failed. I would have had it replaced when the SC was installed a couple of months ago. Lesson learned - If you are installing a SC, install a new Alternator. I hope that is not it, but will advise.
 

FordTechOne

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I've not been able to get back to trouble shooting. I believe the next thing that I will try is disconnecting the alternator power cable to see if that is drawing any power.

Good grief, if that thing is bad. The alternator that I picked up was $340 + the install. I wish I had known that the SC had to be taken off if an alternator failed. I would have had it replaced when the SC was installed a couple of months ago. Lesson learned - If you are installing a SC, install a new Alternator. I hope that is not it, but will advise.
Being that you have an aftermarket supercharger, have you verified that the intercooler pump is not stuck on?
 
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BSouders80

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I felt the SC Coolant lines, squeezed on them and I do not believe there is any flow in the off/sleep position.

I went out and did some more testing a bit ago.

With my alternator power cable hooked up, I am drawing 3.13 amps.
With my alternator power cable not hooked up, I am drawing 0.38 amps.

So - Looks like it is the alternator. Is there anything else associated with that power cable that COULD be drawing power? I kind of pushed the harness around near/under the SC, but no change in amp draws with the alternator power cable hooked up.
 
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