Need expert with alternator/regulator question
Junior Member
Joined: Jun 2015
Posts: 1
Likes: 0
Holy cow!
My 1997 F150 also had a charging problem. It was only putting out 12.25 volts. After changing the alternator, I still only had 12.25 volts. Went through all connections...all O.K. Went through all the fuses and found #19 (air bag) blown. Replaced it and, low and behold, ...Fixed!! Now charging fine!! Man, who'd thought??!!!
Senior Member
Joined: Nov 2006
Posts: 5,495
Likes: 7
From: Memphis, TN 38135, USA, Earth
This shows how to test the alternator, and how it works:
The beeps are most likely from the airbag module, telling you: 1) there are codes, and 2) the airbag bulb is burned out, so it can't flash the code at you.
Yes, it's possible they're related, and this is the most likely location for a combined fault:
The beeps are most likely from the airbag module, telling you: 1) there are codes, and 2) the airbag bulb is burned out, so it can't flash the code at you.
Yes, it's possible they're related, and this is the most likely location for a combined fault:
Junior Member
Joined: May 2017
Posts: 3
Likes: 0
Does anyone know if my voltage regulator is seporate from the alternator?? My truck is not charging.
Also should I pay to have it hooked up to diagnostic or just go ahead and replace. I know it is not charging because I can charge the battery externally and then it will run for a good while as I watch the volt meter slowly head towards 8. Have checked all fuses both under hood and under dash.
My signature is below and I have the heavy duty tow package.
------------------
Black 1997 F-150 Supercab Flairside. 4.6L with Jocobs DIS, K&N Generation II, Cat back Exhaust (my own, nice rumble). 17" Off Road wheel pkg. Lots of body mods. 4 yrs old and still turns heads...
Also should I pay to have it hooked up to diagnostic or just go ahead and replace. I know it is not charging because I can charge the battery externally and then it will run for a good while as I watch the volt meter slowly head towards 8. Have checked all fuses both under hood and under dash.
My signature is below and I have the heavy duty tow package.
------------------
Black 1997 F-150 Supercab Flairside. 4.6L with Jocobs DIS, K&N Generation II, Cat back Exhaust (my own, nice rumble). 17" Off Road wheel pkg. Lots of body mods. 4 yrs old and still turns heads...
Do you know how to use a voltmeter.1.start truck with know charged battery.2.connect red lead of voltmeter to +connection on back of alternator(will be the one wire with the nut holding it on)the black lead to neg.(on battery or any good ground.) Voltmeter will read 14-15 volts output ideally.below 14 volts undercharging.above 15 volts overcharging.expert opion
Junior Member
Joined: May 2017
Posts: 3
Likes: 0
Dallas
Dallas
Do you know how to use a voltmeter.1.start truck with know charged battery.2.connect red lead of voltmeter to +connection on back of alternator(will be the one wire with the nut holding it on)the black lead to neg.(on battery or any good ground.) Voltmeter will read 14-15 volts output ideally.below 14 volts undercharging.above 15 volts overcharging.expert opion
Do you know how to use a voltmeter.1.start truck with know charged battery.2.connect red lead of voltmeter to +connection on back of alternator(will be the one wire with the nut holding it on)the black lead to neg.(on battery or any good ground.) Voltmeter will read 14-15 volts output ideally.below 14 volts undercharging.above 15 volts overcharging.expert opion