Voltage unstable
#16
Guest
Posts: n/a
Re: Re: Voltage unstable
I have thought of this route BUT this problem ONLY happens after the
engine has warmed up. This leads me towards an electrical problem and
your thoughts about a poor earth will be checked. If a poor earth
should this not have shown up when the battery and alternator were
checked?
The unit that controls electrics has just been replaced with no change
to the problem
"Stewart DIBBS" wrote
> "yourpete" <none@000.com> wrote in message
> news:951271_8f4af7ca4a55d1930a8829b577d7fdf6@autob oardz.com...
> > During night driving I have noticed that the head lights
> vary in
> > brightness. They brighten up at about 2500 to 3000 revs and
> dim when
> > the revs drop.
>
> OK, lets look at what causes a visible variation: change in
> voltage. Since
> you say the alternator and battery have tested OK, then its
> likely a
> mechanical rather than an electrical problem.
>
> What causes an alternator to vary voltage? A slipping belt is
> the usual
> reason. A bad ground is another.
>
> > But when in say 4th or 5th gear at about 1500
> > revs(Diesel model) and I lift off the accelerator the lights
> > brighten up...
>
> Have a good look at all the alternator mounting brackets. Is
> anything loose?
> eg the main pivot bolt on to the block. Check all the engine
> block to
> chassis ground links.
>
> Is the crank pulley loose or is a two part balancer type?
> Could be the
> pulley is separating and moving the belt around causing
> slipage or lateral
> movement in the alternator.
>
> SD
--
Posted at author's request, using http://www.AutoBoardz.com interface
Articles individually verified to usenet standards. Visit URL to contact author/report abuse
Thread archive: http://www.AutoBoardz.com/Voltage-un...ict200609.html
engine has warmed up. This leads me towards an electrical problem and
your thoughts about a poor earth will be checked. If a poor earth
should this not have shown up when the battery and alternator were
checked?
The unit that controls electrics has just been replaced with no change
to the problem
"Stewart DIBBS" wrote
> "yourpete" <none@000.com> wrote in message
> news:951271_8f4af7ca4a55d1930a8829b577d7fdf6@autob oardz.com...
> > During night driving I have noticed that the head lights
> vary in
> > brightness. They brighten up at about 2500 to 3000 revs and
> dim when
> > the revs drop.
>
> OK, lets look at what causes a visible variation: change in
> voltage. Since
> you say the alternator and battery have tested OK, then its
> likely a
> mechanical rather than an electrical problem.
>
> What causes an alternator to vary voltage? A slipping belt is
> the usual
> reason. A bad ground is another.
>
> > But when in say 4th or 5th gear at about 1500
> > revs(Diesel model) and I lift off the accelerator the lights
> > brighten up...
>
> Have a good look at all the alternator mounting brackets. Is
> anything loose?
> eg the main pivot bolt on to the block. Check all the engine
> block to
> chassis ground links.
>
> Is the crank pulley loose or is a two part balancer type?
> Could be the
> pulley is separating and moving the belt around causing
> slipage or lateral
> movement in the alternator.
>
> SD
--
Posted at author's request, using http://www.AutoBoardz.com interface
Articles individually verified to usenet standards. Visit URL to contact author/report abuse
Thread archive: http://www.AutoBoardz.com/Voltage-un...ict200609.html
#17
Guest
Posts: n/a
Re: Re: Voltage unstable
I have thought of this route BUT this problem ONLY happens after the
engine has warmed up. This leads me towards an electrical problem and
your thoughts about a poor earth will be checked. If a poor earth
should this not have shown up when the battery and alternator were
checked?
The unit that controls electrics has just been replaced with no change
to the problem
"Stewart DIBBS" wrote
> "yourpete" <none@000.com> wrote in message
> news:951271_8f4af7ca4a55d1930a8829b577d7fdf6@autob oardz.com...
> > During night driving I have noticed that the head lights
> vary in
> > brightness. They brighten up at about 2500 to 3000 revs and
> dim when
> > the revs drop.
>
> OK, lets look at what causes a visible variation: change in
> voltage. Since
> you say the alternator and battery have tested OK, then its
> likely a
> mechanical rather than an electrical problem.
>
> What causes an alternator to vary voltage? A slipping belt is
> the usual
> reason. A bad ground is another.
>
> > But when in say 4th or 5th gear at about 1500
> > revs(Diesel model) and I lift off the accelerator the lights
> > brighten up...
>
> Have a good look at all the alternator mounting brackets. Is
> anything loose?
> eg the main pivot bolt on to the block. Check all the engine
> block to
> chassis ground links.
>
> Is the crank pulley loose or is a two part balancer type?
> Could be the
> pulley is separating and moving the belt around causing
> slipage or lateral
> movement in the alternator.
>
> SD
--
Posted at author's request, using http://www.AutoBoardz.com interface
Articles individually verified to usenet standards. Visit URL to contact author/report abuse
Thread archive: http://www.AutoBoardz.com/Voltage-un...ict200609.html
engine has warmed up. This leads me towards an electrical problem and
your thoughts about a poor earth will be checked. If a poor earth
should this not have shown up when the battery and alternator were
checked?
The unit that controls electrics has just been replaced with no change
to the problem
"Stewart DIBBS" wrote
> "yourpete" <none@000.com> wrote in message
> news:951271_8f4af7ca4a55d1930a8829b577d7fdf6@autob oardz.com...
> > During night driving I have noticed that the head lights
> vary in
> > brightness. They brighten up at about 2500 to 3000 revs and
> dim when
> > the revs drop.
>
> OK, lets look at what causes a visible variation: change in
> voltage. Since
> you say the alternator and battery have tested OK, then its
> likely a
> mechanical rather than an electrical problem.
>
> What causes an alternator to vary voltage? A slipping belt is
> the usual
> reason. A bad ground is another.
>
> > But when in say 4th or 5th gear at about 1500
> > revs(Diesel model) and I lift off the accelerator the lights
> > brighten up...
>
> Have a good look at all the alternator mounting brackets. Is
> anything loose?
> eg the main pivot bolt on to the block. Check all the engine
> block to
> chassis ground links.
>
> Is the crank pulley loose or is a two part balancer type?
> Could be the
> pulley is separating and moving the belt around causing
> slipage or lateral
> movement in the alternator.
>
> SD
--
Posted at author's request, using http://www.AutoBoardz.com interface
Articles individually verified to usenet standards. Visit URL to contact author/report abuse
Thread archive: http://www.AutoBoardz.com/Voltage-un...ict200609.html
#18
Guest
Posts: n/a
Re: Voltage unstable
yourpete wrote:
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
#19
Guest
Posts: n/a
Re: Voltage unstable
yourpete wrote:
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
#20
Guest
Posts: n/a
Re: Voltage unstable
yourpete wrote:
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
#21
Guest
Posts: n/a
Re: Voltage unstable
yourpete wrote:
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
>During night driving I have noticed that the head lights vary in
>brightness. They brighten up at about 2500 to 3000 revs and dim when
>the revs drop. But when in say 4th or 5th gear at about 1500
>revs(Diesel model) and I lift off the accrelator the lights
>brightenup?. Strange. This will voltage varation only happens AFTER
>the engine has warmed up. The brightness varation is also noted if you
>over-ride the interior lights. My garage has replaced the control unit
>but no change. Any suggestions. The battery and alternator have been
>FULLY checked out and found to be OK.
>
I had this same symptom when I swapped in a JDM B18C into a USDM 96 Civic.
The problem was the fact that the USDM car had an Electical Load Detector in
the under-hood fuse box and the JDM ECU does not use one so it was confusing
the JDM ECU and it was "telling" the alternator to stop charging when I would
press on the accelerator. I remover the ELD and all is fine now. It could be
that your ELD (if you have one) is bad, or the connection to it in the under-
hood fuse box needs cleaned.
--
Message posted via CarKB.com
http://www.carkb.com/Uwe/Forums.aspx...-cars/200612/1
Thread
Thread Starter
Forum
Replies
Last Post
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)