2005 Civic EX pulsing headlights, interior lights
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2005 Civic EX pulsing headlights, interior lights
Afformentioned civic has some stramge electrical issues.
Multimeter registers 15.2 volts at times and down to 13.5 volts depending upon what accessories are running, the headlights will pulsate if its the only accessory running, if I turn on the a/c, and defroster the headlights will stop pulsating some of the time.
heres where it gets weirder, the transmission will shift more smoothly when the a/c and rear defrost is on, but whenI turn these off I get much harder and “shaky” shifts (its an automatic), but it never slips out of gear.
I have noticed a direct cor-relation between bad shifts and pulsing headlights, when the headlights dont pulse, the gearbox shifts normally.
What should i be tracking down? This has been going on for over a year, no check engnine ligt, no battery light, engnine otherwise runs perfectly, battery is 6 years old. Is this an alternator issue? Or are there other common electrical issues i need to look for?
Multimeter registers 15.2 volts at times and down to 13.5 volts depending upon what accessories are running, the headlights will pulsate if its the only accessory running, if I turn on the a/c, and defroster the headlights will stop pulsating some of the time.
heres where it gets weirder, the transmission will shift more smoothly when the a/c and rear defrost is on, but whenI turn these off I get much harder and “shaky” shifts (its an automatic), but it never slips out of gear.
I have noticed a direct cor-relation between bad shifts and pulsing headlights, when the headlights dont pulse, the gearbox shifts normally.
What should i be tracking down? This has been going on for over a year, no check engnine ligt, no battery light, engnine otherwise runs perfectly, battery is 6 years old. Is this an alternator issue? Or are there other common electrical issues i need to look for?
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From: The Familiar Realm
Re: 2005 Civic EX pulsing headlights, interior lights
The transmission is electronically controlled with shift solenoids, so any issues with your electrical system can affect it. I would start with the free things by cleaning your grounds and battery terminals. Double check your alternator mounting bolts. They are notorious for working themselves loose and causing issues on this generation.
I have replaced an alternator in one of these before for similar erratic behavior. It would charge as high as 18 volts, and cause the ABS and SRS lights to flicker nonstop.
I have replaced an alternator in one of these before for similar erratic behavior. It would charge as high as 18 volts, and cause the ABS and SRS lights to flicker nonstop.
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Re: 2005 Civic EX pulsing headlights, interior lights
The transmission is electronically controlled with shift solenoids, so any issues with your electrical system can affect it. I would start with the free things by cleaning your grounds and battery terminals. Double check your alternator mounting bolts. They are notorious for working themselves loose and causing issues on this generation.
I have replaced an alternator in one of these before for similar erratic behavior. It would charge as high as 18 volts, and cause the ABS and SRS lights to flicker nonstop.
I have replaced an alternator in one of these before for similar erratic behavior. It would charge as high as 18 volts, and cause the ABS and SRS lights to flicker nonstop.
I had read other places that some people who experienced the same behaviors as mine noticed everything was resolved by the alternator replacement.
I did start with the free stuff yesterday, removed the bumper cover and checked the main grounding points under the headlights, attached to the transmission, the strap from the engnine block to the front core support, I couldn’t find any other engine grounds beyond those, and none looked particularly bad but I cleaned all of them with a wire brush for good measure.
i also will note I can hear a whine through the car stereo speakers now, it’s faint but I can hear it.
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From: The Familiar Realm
Re: 2005 Civic EX pulsing headlights, interior lights
And the alternator's mounting bolts were good and snug? The alternator gets its ground through those mounting points, and will cause issues if they aren't tight. You'll have to remove the power steering pump to double check.
If all else fails, you can bring your alternator to Autozone for a free test, although they don't always catch a bad one.
If all else fails, you can bring your alternator to Autozone for a free test, although they don't always catch a bad one.
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Re: 2005 Civic EX pulsing headlights, interior lights
And the alternator's mounting bolts were good and snug? The alternator gets its ground through those mounting points, and will cause issues if they aren't tight. You'll have to remove the power steering pump to double check.
If all else fails, you can bring your alternator to Autozone for a free test, although they don't always catch a bad one.
If all else fails, you can bring your alternator to Autozone for a free test, although they don't always catch a bad one.
Thread Starter
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Re: 2005 Civic EX pulsing headlights, interior lights
And the alternator's mounting bolts were good and snug? The alternator gets its ground through those mounting points, and will cause issues if they aren't tight. You'll have to remove the power steering pump to double check.
If all else fails, you can bring your alternator to Autozone for a free test, although they don't always catch a bad one.
If all else fails, you can bring your alternator to Autozone for a free test, although they don't always catch a bad one.
Everything is good and snug, I decided to use an OBD2 live scanner and monitor the Voltage that the ECU was reading at various revs, I found the voltage spiking up to 16.9 in some cases, usually between 2000 and 3200 RPM then dropping back to 14.5 after 3200 RPM, I also noticed shifts smooth out tremendously above 3200 RPM.
Also, the gauge cluster is now pulsing in relation to interior lights and headlights.
Edit; Also thanks for the help, I think I am in the right direction but its always nice to have someone to bounce ideas off of.
It would seem that the voltage regulator in the alternator has likely failed, incidentally the alternator is also covered in oil from a valve cover gasket leak that I just resolved a few days ago.
Seems like all signs point to alternator replacement, now the big question; which alternator replacement isn't hot garbage but also won't set me back a ton of cash, rockauto lists an ACDelco unit (which is also preferred according to rockauto) for $115 brand new, not reman. ACDelco units any good or should I look for a particular brand? I don't mind buying an OEM Honda (or whatever their supplier) is, if it only costs a bit more.
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From: The Familiar Realm
Re: 2005 Civic EX pulsing headlights, interior lights
If you can do the work yourself, just get one from Autozone and replace it. The one I got from Autozone for my buddy's 2002 Civic with the same symptoms has been holding up fairly well. It did solve his issues too. You might have to change it every couple of years, but at least you'll have a lifetime warranty on it.
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Re: 2005 Civic EX pulsing headlights, interior lights
Just a follow up.
I ended up ordering an AC Delco alternator off Rockauto and installed it along with a new transmission mount (because it was torn).
Problem solved, no more pulsing lights, the transmission shifts flawlessly now, it feels like brand new again.
I ended up ordering an AC Delco alternator off Rockauto and installed it along with a new transmission mount (because it was torn).
Problem solved, no more pulsing lights, the transmission shifts flawlessly now, it feels like brand new again.
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