Dash lights flickering, alternator tests fine
05-07-2015, 06:09 AM
#1
Registered User
Thread Starter
Dash lights flickering, alternator tests fine
I'm having trouble with my tachometer flickering at idle. It does not flicker when the engine is off and the car is on battery power. Also, my radar detector looses power and shuts down if I idle too long. My battery is about 9 months old (Honda OEM). I've never had a problem with starting.
At idle I'm seeing 14.1 volts at the battery with all accessories off, 14.3 volts with everything (lights/AC/stereo) on. I also had my alternator tested by the guys at the auto parts store and they said it was fine. Like I said, I've never had trouble with starting.
Is it still possible my alternator is faulty, but not to the degree that it fails the test?
At idle I'm seeing 14.1 volts at the battery with all accessories off, 14.3 volts with everything (lights/AC/stereo) on. I also had my alternator tested by the guys at the auto parts store and they said it was fine. Like I said, I've never had trouble with starting.
Is it still possible my alternator is faulty, but not to the degree that it fails the test?
05-07-2015, 06:24 AM
#2
I'm having trouble with my tachometer flickering at idle. It does not flicker when the engine is off and the car is on battery power. Also, my radar detector looses power and shuts down if I idle too long. My battery is about 9 months old (Honda OEM). I've never had a problem with starting.
At idle I'm seeing 14.1 volts at the battery with all accessories off, 14.3 volts with everything (lights/AC/stereo) on. I also had my alternator tested by the guys at the auto parts store and they said it was fine. Like I said, I've never had trouble with starting.
Is it still possible my alternator is faulty, but not to the degree that it fails the test?
At idle I'm seeing 14.1 volts at the battery with all accessories off, 14.3 volts with everything (lights/AC/stereo) on. I also had my alternator tested by the guys at the auto parts store and they said it was fine. Like I said, I've never had trouble with starting.
Is it still possible my alternator is faulty, but not to the degree that it fails the test?
The all-in-one thing is horrible for testing a failed diode pack in the alternator rectifier. Mine also tested fine by that all-in-one method but when I bought a new one and swapped it I had them run it on the bench and it failed.
I'm almost certain that's what your issue is. Make sure you unplug your radar when it's not in use (car parked). It may have a parasitic draw on it, like my bluetooth OBD2 scanner had which is hard on your alternator if you let it sit that way for days at a time and go to start the car. It fried 2 of my alternators.
05-07-2015, 07:54 AM
#3
Registered User
Thread Starter
They used one of the combo battery/alternator testers with it in the car. A reman Denso alternator is only $150 so I think I'll go ahead and change it.
Good call on unplugging the detector. I also have a wifi OBD2 scanner that was the straw that broke my last battery's back when left it plugged in while my car sat when I was on vacation last year.
I'd like to add that when idling I sometimes feel slight shudders from the engine, like a weak misfire, but it never throws a code, and it runs perfectly when the revs are up. I'm wondering if a weak spark could be the culprit.
Good call on unplugging the detector. I also have a wifi OBD2 scanner that was the straw that broke my last battery's back when left it plugged in while my car sat when I was on vacation last year.
I'd like to add that when idling I sometimes feel slight shudders from the engine, like a weak misfire, but it never throws a code, and it runs perfectly when the revs are up. I'm wondering if a weak spark could be the culprit.
05-07-2015, 10:20 AM
#4
The shudder could be a lot of things, but the alternator is not one of them. If the alternator output were to periodically dip for some reason, a healthy battery should easily be able to supply all the juice the engine needs to run.
Think of the battery as a water tower, and the alternator as a pump constantly filling it up. If the pump cuts in and out, the water output spigot does not falter, having all the flow and water pressure it normally supplies due to the nearly full water tank.
Think of the battery as a water tower, and the alternator as a pump constantly filling it up. If the pump cuts in and out, the water output spigot does not falter, having all the flow and water pressure it normally supplies due to the nearly full water tank.
05-07-2015, 10:39 AM
#5
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
Obviously still do a parasitic draw test as well. But this very may be your culprit.
05-21-2015, 04:27 AM
#6
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
Obviously still do a parasitic draw test as well. But this very may be your culprit.
thanks
(I have the flickering dash lights)
05-21-2015, 04:50 AM
#7
Originally Posted by Ap2low' timestamp='1431023990' post='23605084
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
Obviously still do a parasitic draw test as well. But this very may be your culprit.
thanks
(I have the flickering dash lights)
For the $8 it will cost you its well worth the attempt!
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05-21-2015, 06:46 AM
#8
Registered User
Thread Starter
Originally Posted by Thomas Guide' timestamp='1432211248' post='23620285
[quote name='Ap2low' timestamp='1431023990' post='23605084']
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
thanks
(I have the flickering dash lights)
For the $8 it will cost you its well worth the attempt!
[/quote]
The negative battery cable just bolts into the chassis behind the battery, correct? I'll give it a shot. I still have the same flickering after changing my alternator.
Maybe I'm being too picky - its not flickering on and off, but looking closely at the tachometer on full brightness there is a subtle variation in intensity.
05-21-2015, 10:40 AM
#9
Originally Posted by Ap2low' timestamp='1432212642' post='23620302
[quote name='Thomas Guide' timestamp='1432211248' post='23620285']
[quote name='Ap2low' timestamp='1431023990' post='23605084']
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
[quote name='Ap2low' timestamp='1431023990' post='23605084']
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
thanks
(I have the flickering dash lights)
For the $8 it will cost you its well worth the attempt!
[/quote]
The negative battery cable just bolts into the chassis behind the battery, correct? I'll give it a shot. I still have the same flickering after changing my alternator.
Maybe I'm being too picky - its not flickering on and off, but looking closely at the tachometer on full brightness there is a subtle variation in intensity.
[/quote]
This is very interesting. What other symptoms might one experience with this bad battery cable? (I'd like to see if there's more that can help myself and others).
For $8, seems to be worth a shot. Is this just an OEM replacement?
05-21-2015, 11:04 AM
#10
Originally Posted by solitarycheese' timestamp='1432219619' post='23620452
[quote name='Ap2low' timestamp='1432212642' post='23620302']
[quote name='Thomas Guide' timestamp='1432211248' post='23620285']
[quote name='Ap2low' timestamp='1431023990' post='23605084']
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
[quote name='Thomas Guide' timestamp='1432211248' post='23620285']
[quote name='Ap2low' timestamp='1431023990' post='23605084']
Replace your negative battery terminal cable with a 2g cable from the auto parts. My car suffered the same things, flickering dash lights, headlights, and eventually stalling at idle. Changed the alternator twice with a re manufactured one and the problem was still there. Paid $700 for a new alternator from Honda, problem was still there. Changed the battery and still nothing, changed the negative battery cable and terminal and my problems went away and have stayed away!
Obviously still do a parasitic draw test as well. But this very may be your culprit.
thanks
(I have the flickering dash lights)
For the $8 it will cost you its well worth the attempt!
[/quote]
The negative battery cable just bolts into the chassis behind the battery, correct? I'll give it a shot. I still have the same flickering after changing my alternator.
Maybe I'm being too picky - its not flickering on and off, but looking closely at the tachometer on full brightness there is a subtle variation in intensity.
[/quote]
This is very interesting. What other symptoms might one experience with this bad battery cable? (I'd like to see if there's more that can help myself and others).
For $8, seems to be worth a shot. Is this just an OEM replacement?
[/quote]
When my car had these issues my dash lights would flicker and at the same time the vsa eps (!) light would turn on as well as my radio cutting off.
If it was at night and my headlights were on with the ac on the car would sometimes stall while driving while doing all of the above things. It was a nightmare
I opted for a after market battery cable because it was a 2g wire but I am sure a oem one would work and should cost around $12-$15 at your local dealer
Here is my thread with a lot of info as well as more detailed explanations of what I was experiencing https://www.s2ki.com/s2000/topic/110...ter-lights-up/