FAQ |
Members List |
Social Groups |
Calendar |
Search |
Today's Posts |
#1
|
|||
|
|||
Generator light on
Needs some advice... generator light is on in my dash and the generators tests out ok, Next step is to test the voltage regulator but how often do those really go out? Any other suggestions on what could be wrong and the solution?
Jim |
#2
|
||||
|
||||
I had this problem a few years ago. It was due to a defective reproduction wiring harness. Maybe a bad dash ground or a blown fuse?
__________________
Ken '68 GTO - Ram Air II 464 - 236/242 roller - 9.5” TSP converter - 3.55 posi (build thread | walk around) '95 Comp T/A #6 M6 - bone stock (pics) |
#3
|
||||
|
||||
Is it on steady and bright, or does it fade in and out?
|
#4
|
|||
|
|||
Stays on steady without any flickering.
|
#5
|
|||
|
|||
Wiring harness is the original one to the car.
|
#6
|
||||
|
||||
If the light stays on steady and the alternator output is good. As others have said, I'd suspect the wiring, fuse or ground. Some smart guy with a wiring diagram could probably find the likely suspect.
|
#7
|
|||
|
|||
Thanks for the tips, I'll look at the wiring and fuse a bit harder to see if that my problem. Appreciate the help.
Jim |
#8
|
||||
|
||||
Had this issue once. Alternator functioned perfectly. Turned out to be the voltage regulator that was keeping the generator light on.
__________________
1968 Pontiac GTO - Verdoro over Ivy Gold - 400/4-speed/3.08 1987 Pontiac Grand Prix - Sage/Sage/Sage - GM 305/Th200-4r 2004 Pontiac GTO - IBM over Black - LSx 440/6-speed/4.10 SRA - Single Digit Stick Shift |
#9
|
|||
|
|||
Great suggestion as well.
|
#10
|
||||
|
||||
I would check all the wiring to the regulator. There is a wire in that regulator harness that feeds a ground to the light & then flips & provides voltage when charging that puts the light out. Not sure what one off hand. you could also have a bad regulator, even though your getting correct voltage when running.
__________________
68 GTO 4-spd Convertible 78 S/E Trans am L78, WS6 Auto 78 S/E Trans am W72, WS6 Auto 79 10th aniv W72 Trans am 80 Indy pace car Trans am 89 Trans am GTA |
#11
|
|||
|
|||
Check fuse
|
#12
|
||||
|
||||
I beleive if its a fuse, the light only comes on when its running, but off when just the ignition is on. Could be wrong on that, but I believe that's what happens.
The function is pretty simple though, the light bulb has power from the fuse block on one end & finds ground through the regulator. When the engine is running, voltage is then produced from the regulator & the ground the bulb had turns into what ever voltage is coming from the charging system. IE 13.5 +/- Because this same voltage is going to the fuse block, both sides of the bulb see the exact same voltage & the light goes out. Most of you guys know that already, but seems worth mentioning, because it makes trouble shooting it so much easier. Anybody have the wiring diagram handy? I have it at home & can post later, but I want to say it was a brown or tan wire between the regulator & bulb.
__________________
68 GTO 4-spd Convertible 78 S/E Trans am L78, WS6 Auto 78 S/E Trans am W72, WS6 Auto 79 10th aniv W72 Trans am 80 Indy pace car Trans am 89 Trans am GTA |
#13
|
|||
|
|||
Thanks for all the help, issued fixed. It was a combo of bad fuse and loose wiring to voltage regulator.
Appreciate everyones input, cut down on the time to fix for sure. Jim |
#14
|
||||
|
||||
Excellent!
And ragtop ... excellent explanation of how the light worked, I had no idea it was that simple. |
#15
|
||||
|
||||
Something I never noticed until tonight. When you shut off the engine, the bulb finds ground from other circuits right when the power is cut from the ignition switch. Because the engine is still momentarily turning the alternator, the bulb lights until the alternator stops turning & making power. Complete opposite of when you have the ignition switch on & engine not running. Bulb lights in both cases, just reversed polarity.
Thought it was worth mentioning.
__________________
68 GTO 4-spd Convertible 78 S/E Trans am L78, WS6 Auto 78 S/E Trans am W72, WS6 Auto 79 10th aniv W72 Trans am 80 Indy pace car Trans am 89 Trans am GTA |
#16
|
||||
|
||||
Which fuse was bad?
__________________
Chris Collier 1969 firebird, pro touring build. Full Global West suspension 474 Stroker with Molnar Crank and Rods, DCI Ram Air 5 Top end, Holley fuel injection, Vince Janis 200-4R trans "There is no such thing as too much horsepower" |
Reply |
Thread Tools | |
Display Modes | |
|
|