Low voltage while driving
Thread Starter
Burning Brakes
Joined: Jun 2009
Posts: 977
Likes: 1
From: Voorhees NJ
Low voltage while driving
2006 C6 Convertible
Added 2 JL subs behind seats...Activated Arc Audio 500.1 amp in pass footwell that had been previously installed on top of Arc 125.4 in stock location...Had issue with previous negative battery terminal, so I replaced pos/neg cable to starter...Added Optima battery D75/25 with top and side terminals for audio system connections...Added curb alert sensor in footwell also...
Installer had to lean on pass side sill to do some of the install, and while leaning there, he bent power seat switch down slightly...When finished, he pushed switch back to get seat in rear position...When i picked up car, I cranked up the tunes and went for a hour ride and listened to music...Parked the car in the garage overnight and the seat switch was stuck in the backward position trying to make the seat go backwards all the time...I heard a clicking on and off the next day which was the seat trying to move further and then the motor has a circuit breaker which would shut off when it overheated...It would cool down and then start the process again...
Question is, intermittently the voltage only charges at 11.2-11.5 while driving and 12-12.5 while idling..It used to charge at 13.8-14.3 normally...When this happens, the ABS and service active handling lights come on...Tested battery and all seems fine...Tested alternator and its charging 13 with 15 volts at battery while idling...Using electrical meter so it doesn't have more than 2 decimals...
Question, could I have damaged module or computer with the seat trying to move consistently and could it be fixed with a reflash??? Would a Tech 2 find the issue??? I am going to snug all nuts on the starter and check ground to block and frame again...Also has problems with FOBS not detected once in a while...Would touching pos/neg cables together off battery reset anything??
Driving me crazy...Help...
Added 2 JL subs behind seats...Activated Arc Audio 500.1 amp in pass footwell that had been previously installed on top of Arc 125.4 in stock location...Had issue with previous negative battery terminal, so I replaced pos/neg cable to starter...Added Optima battery D75/25 with top and side terminals for audio system connections...Added curb alert sensor in footwell also...
Installer had to lean on pass side sill to do some of the install, and while leaning there, he bent power seat switch down slightly...When finished, he pushed switch back to get seat in rear position...When i picked up car, I cranked up the tunes and went for a hour ride and listened to music...Parked the car in the garage overnight and the seat switch was stuck in the backward position trying to make the seat go backwards all the time...I heard a clicking on and off the next day which was the seat trying to move further and then the motor has a circuit breaker which would shut off when it overheated...It would cool down and then start the process again...
Question is, intermittently the voltage only charges at 11.2-11.5 while driving and 12-12.5 while idling..It used to charge at 13.8-14.3 normally...When this happens, the ABS and service active handling lights come on...Tested battery and all seems fine...Tested alternator and its charging 13 with 15 volts at battery while idling...Using electrical meter so it doesn't have more than 2 decimals...
Question, could I have damaged module or computer with the seat trying to move consistently and could it be fixed with a reflash??? Would a Tech 2 find the issue??? I am going to snug all nuts on the starter and check ground to block and frame again...Also has problems with FOBS not detected once in a while...Would touching pos/neg cables together off battery reset anything??
Driving me crazy...Help...
Racer
Joined: Dec 2011
Posts: 268
Likes: 6
From: Barstow Ca
If the alternator is charging intermittently then thats more than likely your problem. Just checking the voltage from the alternator isn't testing it. I replaced the battery in my wifes car when it died, checked the voltage with the new one and thought it was good. A day later the battery was run down again. I found out the car was charging intermittently. I changed the alternator and all was good again.
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,628
Double edge sword,
We drive the vets for the most part on the street at low revs, which is when the alternator is putting out the least amount of amps.
Double check the amperage demand on the new sound system, but sounds like you need to change the alternator out to a higher output unit.
The stock alternator puts out around 150 amps are full tilt/max rev, but you may need to go with a 275amp to keep up with the sound system at low rpm speeds instead.
We drive the vets for the most part on the street at low revs, which is when the alternator is putting out the least amount of amps.
Double check the amperage demand on the new sound system, but sounds like you need to change the alternator out to a higher output unit.
The stock alternator puts out around 150 amps are full tilt/max rev, but you may need to go with a 275amp to keep up with the sound system at low rpm speeds instead.
Thread Starter
Burning Brakes
Joined: Jun 2009
Posts: 977
Likes: 1
From: Voorhees NJ
Double edge sword,
We drive the vets for the most part on the street at low revs, which is when the alternator is putting out the least amount of amps.
Double check the amperage demand on the new sound system, but sounds like you need to change the alternator out to a higher output unit.
The stock alternator puts out around 150 amps are full tilt/max rev, but you may need to go with a 275amp to keep up with the sound system at low rpm speeds instead.
We drive the vets for the most part on the street at low revs, which is when the alternator is putting out the least amount of amps.
Double check the amperage demand on the new sound system, but sounds like you need to change the alternator out to a higher output unit.
The stock alternator puts out around 150 amps are full tilt/max rev, but you may need to go with a 275amp to keep up with the sound system at low rpm speeds instead.
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,628
Do the math on the amps amperage needed again.
Between the two, I am seeing around 100 amps needed for the two for amplifiers alone, and your 170 alternator is only putting out 100 amps at idle. So at best, the alternator is only keeping up with the amplifiers, and the car itself is draining down the battery at idle/low revs since the alternator is not able to keep up with the demand for both the car needs, and the amplifier needs. So not only are you going to end up killing the battery quickly from it being cycled way down at each idling type speeds, but going to be wearing out the alternator (it's contact bushings) since it always going to be charging as well.
https://www.dcpowerinc.com/high-outp...ne=6.0L+LS2+V8
And the 300amp alternator has a idle amperage of 225 amps at idle, and would be the way to go for your vet that spends most of it street driving life just off idle.
Between the two, I am seeing around 100 amps needed for the two for amplifiers alone, and your 170 alternator is only putting out 100 amps at idle. So at best, the alternator is only keeping up with the amplifiers, and the car itself is draining down the battery at idle/low revs since the alternator is not able to keep up with the demand for both the car needs, and the amplifier needs. So not only are you going to end up killing the battery quickly from it being cycled way down at each idling type speeds, but going to be wearing out the alternator (it's contact bushings) since it always going to be charging as well.
https://www.dcpowerinc.com/high-outp...ne=6.0L+LS2+V8
And the 300amp alternator has a idle amperage of 225 amps at idle, and would be the way to go for your vet that spends most of it street driving life just off idle.
Thread Starter
Burning Brakes
Joined: Jun 2009
Posts: 977
Likes: 1
From: Voorhees NJ
Do the math on the amps amperage needed again.
Between the two, I am seeing around 100 amps needed for the two for amplifiers alone, and your 170 alternator is only putting out 100 amps at idle. So at best, the alternator is only keeping up with the amplifiers, and the car itself is draining down the battery at idle/low revs since the alternator is not able to keep up with the demand for both the car needs, and the amplifier needs. So not only are you going to end up killing the battery quickly from it being cycled way down at each idling type speeds, but going to be wearing out the alternator (it's contact bushings) since it always going to be charging as well.
https://www.dcpowerinc.com/high-outp...ne=6.0L+LS2+V8
And the 300amp alternator has a idle amperage of 225 amps at idle, and would be the way to go for your vet that spends most of it street driving life just off idle.
Between the two, I am seeing around 100 amps needed for the two for amplifiers alone, and your 170 alternator is only putting out 100 amps at idle. So at best, the alternator is only keeping up with the amplifiers, and the car itself is draining down the battery at idle/low revs since the alternator is not able to keep up with the demand for both the car needs, and the amplifier needs. So not only are you going to end up killing the battery quickly from it being cycled way down at each idling type speeds, but going to be wearing out the alternator (it's contact bushings) since it always going to be charging as well.
https://www.dcpowerinc.com/high-outp...ne=6.0L+LS2+V8
And the 300amp alternator has a idle amperage of 225 amps at idle, and would be the way to go for your vet that spends most of it street driving life just off idle.
for one start the other day...Since you seem to know electrical, would a bad diode in the alternator create these symptoms??? Thanks for your help, it is appreciated...
Scott
Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,628
If you understand how an alternator works, then yes, or could be that one bushing to the armature is not making contact full time, or there is a problem with one of the diodes in the bride rectifer not making contact full time.
Armature turns against magnets force to create a AC electrical charge. The bushing make contact to the Armature as the first connection, then the AC voltage is sent through the bridge rectifier (series diodes) from the two bushing to convert the AC to DC current, then through the voltage regulator to cap the voltage at 14.2 volts/ regulate when to send power out to charge the system.
If either a brushing is not making clean contact to the Armature contact pads, or one of the diodes goes out in the Bride rectifier, then you only get a half wave of current into the Regulator.
Look at this and understand that AC is a series of positive push and negative pulls through a singe wire in cycles. So each AC wire first pushes positive for a half cycle, then pull negative for the other half cycle.
On the two wires/brushes on the alternator, while one is in its positive cycle push (+ what ever voltage above 0 voltage), the other side is at is negative pull cycle instead (- what ever voltage below 0 voltage). So for half a cycle, one side pushes, while the other side pulls, then for the other half phase, the wires swap pulling and pushing instead.
The bridge rectifiers changes these AC push and pulls of currents through each AC wire to constant line positives and negatives instead to the DC lines.
The arrows on the diagram are gates that only allow AC current to flow the single direction through the rectifier, Hence only allows the AC push phase of each wire to push current through the DC positive side wire, then then only allows the AC negative pulls to pull back on the negative side.
Since the two AC brushes/wires out of the Armature are out of phase with each other, as one is pulling, the other is pushing at the same time. If only one wire is connected to the rectifier, then it only pushes for a half cycle, then will pull for the other half cycle (lose half a cycle)
Lastly, the voltage is capped at about 14.2 DC volts out of the regulator, while the armature pushes out a much higher voltage than that to rectifier and regulator instead. So even with a half phase to the rectifier/regulator only, if the alternator is spinning fast enough, it will still be able to send out more than 14.2 volts, but much less amperage.
Armature turns against magnets force to create a AC electrical charge. The bushing make contact to the Armature as the first connection, then the AC voltage is sent through the bridge rectifier (series diodes) from the two bushing to convert the AC to DC current, then through the voltage regulator to cap the voltage at 14.2 volts/ regulate when to send power out to charge the system.
If either a brushing is not making clean contact to the Armature contact pads, or one of the diodes goes out in the Bride rectifier, then you only get a half wave of current into the Regulator.
Look at this and understand that AC is a series of positive push and negative pulls through a singe wire in cycles. So each AC wire first pushes positive for a half cycle, then pull negative for the other half cycle.
On the two wires/brushes on the alternator, while one is in its positive cycle push (+ what ever voltage above 0 voltage), the other side is at is negative pull cycle instead (- what ever voltage below 0 voltage). So for half a cycle, one side pushes, while the other side pulls, then for the other half phase, the wires swap pulling and pushing instead.
The bridge rectifiers changes these AC push and pulls of currents through each AC wire to constant line positives and negatives instead to the DC lines.
The arrows on the diagram are gates that only allow AC current to flow the single direction through the rectifier, Hence only allows the AC push phase of each wire to push current through the DC positive side wire, then then only allows the AC negative pulls to pull back on the negative side.
Since the two AC brushes/wires out of the Armature are out of phase with each other, as one is pulling, the other is pushing at the same time. If only one wire is connected to the rectifier, then it only pushes for a half cycle, then will pull for the other half cycle (lose half a cycle)
Lastly, the voltage is capped at about 14.2 DC volts out of the regulator, while the armature pushes out a much higher voltage than that to rectifier and regulator instead. So even with a half phase to the rectifier/regulator only, if the alternator is spinning fast enough, it will still be able to send out more than 14.2 volts, but much less amperage.
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Race Director
Joined: Dec 2013
Posts: 12,502
Likes: 3,628
If you understand how an alternator works, then yes, or could be that one bushing to the armature is not making contact full time, or there is a problem with one of the diodes in the bride rectifer not making contact full time.
Armature turns against magnets force to create a AC electrical charge. The bushing make contact to the Armature as the first connection, then the AC voltage is sent through the bridge rectifier (series diodes) from the two bushing to convert the AC to DC current, then through the voltage regulator to cap the voltage at 14.2 volts/ regulate when to send power out to charge the system.
If either a brushing is not making clean contact to the Armature contact pads, or one of the diodes goes out in the Bride rectifier, then you only get a half wave of current into the Regulator.
Look at this and understand that AC is a series of positive push and negative pulls through a singe wire in cycles. So each AC wire first pushes positive for a half cycle, then pull negative for the other half cycle.
On the two wires/brushes on the alternator, while one is in its positive cycle push (+ what ever voltage above 0 voltage), the other side is at is negative pull cycle instead (- what ever voltage below 0 voltage). So for half a cycle, one side pushes, while the other side pulls, then for the other half phase, the wires swap pulling and pushing instead.
The bridge rectifiers changes these AC push and pulls of currents through each AC wire to constant line positives and negatives instead to the DC lines.
The arrows on the diagram are gates that only allow AC current to flow the single direction through the rectifier, Hence only allows the AC push phase of each wire to push current through the DC positive side wire, then then only allows the AC negative pulls to pull back on the negative side.
Since the two AC brushes/wires out of the Armature are out of phase with each other, as one is pulling, the other is pushing at the same time. If only one ac wire is connected to the rectifier (or making current through in the case of one diode having not working full time), then it only pushes for a half cycle, then will pull for the other half cycle (lose half a cycle)
Lastly, the voltage is capped at about 14.2 DC volts out of the regulator, while the armature pushes out a much higher voltage than that to rectifier and regulator instead. So even with a half phase to the rectifier/regulator only, if the alternator is spinning fast enough, it will still be able to send out more than 14.2 volts, but much less amperage.
Armature turns against magnets force to create a AC electrical charge. The bushing make contact to the Armature as the first connection, then the AC voltage is sent through the bridge rectifier (series diodes) from the two bushing to convert the AC to DC current, then through the voltage regulator to cap the voltage at 14.2 volts/ regulate when to send power out to charge the system.
If either a brushing is not making clean contact to the Armature contact pads, or one of the diodes goes out in the Bride rectifier, then you only get a half wave of current into the Regulator.
Look at this and understand that AC is a series of positive push and negative pulls through a singe wire in cycles. So each AC wire first pushes positive for a half cycle, then pull negative for the other half cycle.
On the two wires/brushes on the alternator, while one is in its positive cycle push (+ what ever voltage above 0 voltage), the other side is at is negative pull cycle instead (- what ever voltage below 0 voltage). So for half a cycle, one side pushes, while the other side pulls, then for the other half phase, the wires swap pulling and pushing instead.
The bridge rectifiers changes these AC push and pulls of currents through each AC wire to constant line positives and negatives instead to the DC lines.
The arrows on the diagram are gates that only allow AC current to flow the single direction through the rectifier, Hence only allows the AC push phase of each wire to push current through the DC positive side wire, then then only allows the AC negative pulls to pull back on the negative side.
Since the two AC brushes/wires out of the Armature are out of phase with each other, as one is pulling, the other is pushing at the same time. If only one ac wire is connected to the rectifier (or making current through in the case of one diode having not working full time), then it only pushes for a half cycle, then will pull for the other half cycle (lose half a cycle)
Lastly, the voltage is capped at about 14.2 DC volts out of the regulator, while the armature pushes out a much higher voltage than that to rectifier and regulator instead. So even with a half phase to the rectifier/regulator only, if the alternator is spinning fast enough, it will still be able to send out more than 14.2 volts, but much less amperage.
Last edited by Dano523; Jun 1, 2014 at 10:50 PM.