Voltage meter (dips)

Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's, Olds 98 91-96, Buick Lesabres and Park Avenue 91-96. Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
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Mitchell77
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Voltage meter (dips)

Post by Mitchell77 »

[*]ok I have posted about my voltage meter before and if u haven't read my voltage meter dips low when I go into reverse ,and sometimes it would dip low when I come to a complete stop.
* I have checked and replaced cables 4 times with oem style no change .
I have checked my wire harness 3 times to see if it was a short and I have had no luck...
What could cause the power source to dip like this , oh yea and I solved my battery drain problem, my alternator wire was broken....
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harofreak00
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Re: Voltage meter (dips)

Post by harofreak00 »

Have you verified this with a meter and not just the instrument cluster? The cluster gauge is horribly inaccurate.

Have you had the alternator tested?

Are you seeing the lights dim?

If you are using a meter, what kind of voltage are you seeing? and how much dip?
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95naSTA
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Re: Voltage meter (dips)

Post by 95naSTA »

Did you replace the ground cable from the battery to the chassis?
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Mitchell77
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Re: Voltage meter (dips)

Post by Mitchell77 »

harofreak00 wrote:Have you verified this with a meter and not just the instrument cluster? The cluster gauge is horribly inaccurate.

Have you had the alternator tested?

Are you seeing the lights dim?

If you are using a meter, what kind of voltage are you seeing? and how much dip?
*Yes I have verified the voltage drops with a meter and not just the cluster.
*The alternator has been bench tested and on car tested its good.
*I don't ALWAYS see the light dim but every now and then I do..
*I will check the brand of my voltage meter don't kno it.
*My voltage is goin from 14.5- 12.3 when it dips....
Mitchell77
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Re: Voltage meter (dips)

Post by Mitchell77 »

95naSTA wrote:Did you replace the ground cable from the battery to the chassis?
Yes sir about 4 times so far each time a bit different.
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harofreak00
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Re: Voltage meter (dips)

Post by harofreak00 »

You either have a poor connection on the terminal L signal, or your alternator is intermittently failing.
When the ignition switch is placed in the RUN position, voltage is supplied to generator terminal L by the PCM, turning on the regulator. The generator's voltage regulator controls current to the rotor, thereby controlling the output voltage. The rotor current is proportional to the electrical pulse width supplied by the regulator. When the engine is started, the regulator senses generator rotation by detecting AC voltage at the stator through an internal wire. Once the engine is running, the regulator varies the field current by controlling the pulse width. This regulates the generator output voltage for proper battery charging and electrical system operation. The generator F terminal is connected internally to the voltage regulator and externally to the PCM. The PCM monitors the field voltage on the generator F terminal.
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Andrew - owner/operator of Bonnevilles Unlimited
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2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler
Mitchell77
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Re: Voltage meter (dips)

Post by Mitchell77 »

harofreak00 wrote:You either have a poor connection on the terminal L signal, or your alternator is intermittently failing.
When the ignition switch is placed in the RUN position, voltage is supplied to generator terminal L by the PCM, turning on the regulator. The generator's voltage regulator controls current to the rotor, thereby controlling the output voltage. The rotor current is proportional to the electrical pulse width supplied by the regulator. When the engine is started, the regulator senses generator rotation by detecting AC voltage at the stator through an internal wire. Once the engine is running, the regulator varies the field current by controlling the pulse width. This regulates the generator output voltage for proper battery charging and electrical system operation. The generator F terminal is connected internally to the voltage regulator and externally to the PCM. The PCM monitors the field voltage on the generator F terminal.
Do u think a new wire harness would do anything?
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harofreak00
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Re: Voltage meter (dips)

Post by harofreak00 »

With a proper scan-tool you can see the signal that the PCM is sending and receiving, then you could verify if that same signal is being received by the alternator. Without doing further diagnostic work, you're just a parts changer.
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2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler
Mitchell77
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Re: Voltage meter (dips)

Post by Mitchell77 »

Lol thanks
Mitchell77
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Re: Voltage meter (dips)

Post by Mitchell77 »

Lol thanks
What is an example of a proper scan tool. Can u be specific, what do u like to use ?
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harofreak00
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Re: Voltage meter (dips)

Post by harofreak00 »

I use a Tech2 and an Autel MS906BT in my shop. Any decent mechanic would have something comparable.
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2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler
Mitchell77
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Re: Voltage meter (dips)

Post by Mitchell77 »

I'm not a mechanic boss.... I don't now why that's important. Anyone and everyone who cares work on their car the best they can... I'm just try guy sorry bother
Thanks for the snappy replys.
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harofreak00
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Re: Voltage meter (dips)

Post by harofreak00 »

You're misreading me, I'm not being snappy. I'm saying that any decent mechanic SHOP would have a tool that could read this data.
Andrew - owner/operator of Bonnevilles Unlimited
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2004 Bonneville GXP | 60k | White Gold Tricoat | custom built supercharged 3800 hot rod | garage queen
1997 Corvette | 57k | Silver Metallic | Z06 wheels | Date-night Hauler/Parts runner
2014 Town & Country Limited | Cashmere Pearl | 115k | Family Hauler
2002 Ram 1500 Quad Cab Sport | Black| 280k | Official Bonneville Hauler
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