99 f150 electrical problem
Logistics Pro
Joined: Jan 2001
Posts: 3,740
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From: Central NYS
So if you got 0.0amps, you probably should open up your meter and see if you blew the internal fuse that protects the amp side of the meter. If so, replace the fuse and try again.
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Freshman User
Joined: Feb 2017
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pdqford, yes, the red is the one i switched. i tested both fuses in my multi meter, they both tested good. I am going to borrow a friends multimeter and see if mine is faulty, or what is going on.
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Freshman User
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Quick update..
Friday around 2pm, (battery was at 10v) i jump started the truck and let it run for about ten minutes. after shutting it off, I worked on the brake lights for an hour or so. I found a wire on the brake switch located on the brake pedal that was loose. i pushed it back in and sure enough, i have brake lights now. after i was done, I volt checked the battery. It was reading 11.5 V. I wanted to test the drain down and see how long it takes to kill the truck. I checked it this morning, it was at 11.4 volts. checked it again just now (10:10pm CST) and it is still at 11.4 V. ?????? I will continue to leave it sitting and see if it drains down I guess...
The truck was a gift to me, and the previous owner (a family member) only had it a couple weeks. he thought he was going to have to send his wifes car to the shop. he ended up not having to, so it sat for the time he had it.
The only info i have on the truck is the battery was new when he got it, and he said its dead now, it has a drain. maybe it had something to do with that loose wire?? maybe it takes it a week or so to drain?? I am not sure yet.
I apologize for my lack of knowledge on it, and thank you all for your help so far. hopefully I will have more details soon. I will keep updating as I go.
Again, Thank you all
Friday around 2pm, (battery was at 10v) i jump started the truck and let it run for about ten minutes. after shutting it off, I worked on the brake lights for an hour or so. I found a wire on the brake switch located on the brake pedal that was loose. i pushed it back in and sure enough, i have brake lights now. after i was done, I volt checked the battery. It was reading 11.5 V. I wanted to test the drain down and see how long it takes to kill the truck. I checked it this morning, it was at 11.4 volts. checked it again just now (10:10pm CST) and it is still at 11.4 V. ?????? I will continue to leave it sitting and see if it drains down I guess...
The truck was a gift to me, and the previous owner (a family member) only had it a couple weeks. he thought he was going to have to send his wifes car to the shop. he ended up not having to, so it sat for the time he had it.
The only info i have on the truck is the battery was new when he got it, and he said its dead now, it has a drain. maybe it had something to do with that loose wire?? maybe it takes it a week or so to drain?? I am not sure yet.
I apologize for my lack of knowledge on it, and thank you all for your help so far. hopefully I will have more details soon. I will keep updating as I go.
Again, Thank you all
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Freshman User
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Checked it again just now, and it is still at 11.4 volts. On a side not, the temp was almost 90° yesterday afternoon, a cold front came in last night and it was down in the 40s this morning. i know thats not super cold, but it is a major drop in temp in a short period of time.
Lead Driver
Joined: Sep 2006
Posts: 7,907
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11.4 is not a fully charged battery.
If it has not changed over three tests the drain is not present except for the computer which always takes a small amount to maintain it's memory.
Use your voltmeter to check the voltage at the battery right after starting.
You should see a voltage level above 14 volts or a bit higher.
This indicates the Alternator is replacing the charge in the battery.
Normally a fully charged battery while running, the system voltage should be about 14 to 14.4 volts.
After shut down the battery will read around 13 and then drop back to about 12.6 +/- in a normally operating system without faults.
The voltmeter tells you about all you need to know about system performance if you interpret the readings correctly under each operating condition.
Good luck.
If it has not changed over three tests the drain is not present except for the computer which always takes a small amount to maintain it's memory.
Use your voltmeter to check the voltage at the battery right after starting.
You should see a voltage level above 14 volts or a bit higher.
This indicates the Alternator is replacing the charge in the battery.
Normally a fully charged battery while running, the system voltage should be about 14 to 14.4 volts.
After shut down the battery will read around 13 and then drop back to about 12.6 +/- in a normally operating system without faults.
The voltmeter tells you about all you need to know about system performance if you interpret the readings correctly under each operating condition.
Good luck.
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Freshman User
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Thank you Bluegrass.
I checked it again before starting, it was at 11.36. I went ahead and started it and it read 14.01 while running. I let it run for 10 minutes, killed it and immediately checked it again. it read 13.8 with the motor off right after I shut it off. i waited 10 minutes, checked it again, it is at 12.00 volts. this is similar to that it did last time. it went down to 11.4 and stayed there. Is that normal? perhaps everything shutting down is causing it to come down to 11.4, then it just stays there??
I will continue to monitor and update tomorrow.
Thank you!
I checked it again before starting, it was at 11.36. I went ahead and started it and it read 14.01 while running. I let it run for 10 minutes, killed it and immediately checked it again. it read 13.8 with the motor off right after I shut it off. i waited 10 minutes, checked it again, it is at 12.00 volts. this is similar to that it did last time. it went down to 11.4 and stayed there. Is that normal? perhaps everything shutting down is causing it to come down to 11.4, then it just stays there??
I will continue to monitor and update tomorrow.
Thank you!
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Lead Driver
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At this point you see the alternator is outputting so is working.
Now you must get into drain isolation testing.
Best to rig up a test light using a small 12 volt lamp of low wattage.
This should light when installed in series with one of the battery cables to show the drain.
As you open each fuse position one at a time, note when the lamp goes dim or out.
That circuit is suspect.
Note that the under hood light should be removed, all doors closed and wait about 30 minutes before beginning the test. There is electronics still alive for awhile after you shut to motor off. It may even be one of those circuits.
Good luck.
Now you must get into drain isolation testing.
Best to rig up a test light using a small 12 volt lamp of low wattage.
This should light when installed in series with one of the battery cables to show the drain.
As you open each fuse position one at a time, note when the lamp goes dim or out.
That circuit is suspect.
Note that the under hood light should be removed, all doors closed and wait about 30 minutes before beginning the test. There is electronics still alive for awhile after you shut to motor off. It may even be one of those circuits.
Good luck.
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Freshman User
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Thank you sam.
I drove the truck this morning about 60 miles. I am going to start a new thread in this same category. thank you all for your help on this thread. I will keep updating this issue as I sort through it all.
I drove the truck this morning about 60 miles. I am going to start a new thread in this same category. thank you all for your help on this thread. I will keep updating this issue as I sort through it all.
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