Battery light flickering
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Laughing Gas
Joined: Mar 2017
Posts: 833
Likes: 4
Battery light flickering
I had the alternator bench tested and I was told that it’s working fine. No sure what all he did but he hooked it up on a belt, drove it with a motor and monitored output voltage, at minimum.
The battery light flickers more when under heavier throttle OR when it’s cold.
My battery cables seem fine but the passenger side body ground is a little suspect. Would that cause this? Is there anything I am missing?
thanks
The battery light flickers more when under heavier throttle OR when it’s cold.
My battery cables seem fine but the passenger side body ground is a little suspect. Would that cause this? Is there anything I am missing?
thanks
Post Fiend
Joined: Apr 2002
Posts: 19,311
Likes: 97
From: Waterloo, Iowa
It's a package deal, I would have the battery tested too, it will eventually at least be damaged by a faulty alternator, and vice versa. Even a paper thin, nearly invisible layer of corrosion on ground or cable connections is enough to cripple alternator output. Many tests can be done with a simple voltmeter if you know what to look for.
Alternator Testing
Alternator Testing
Fleet Mechanic
Joined: Jul 2005
Posts: 1,800
Likes: 52
From: Southern Colorado
Not all 'alternator testers' can fully and properly test an alternator. I would do some realtime monitoring of voltage at the battery with the truck idling, and with and without all accessories running. You should still see 14+v with the fan on high, high beams on, cigarette lighter pushed in, etc. If you don't, then your alternator may be suspect. Cleaning all grounds is (of course) always a good idea.
I had a flickering battery light years ago and it was the alternator.
I had a flickering battery light years ago and it was the alternator.
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Laughing Gas
Joined: Mar 2017
Posts: 833
Likes: 4
Ran some tests this evening with Forscan and the headlights.
Within the app I am getting ~11.5 volts and it intermittently jumps to ~14.0. The headlights brighten and dim with the voltage, but the battery light is more intermittent.
I’ll get the batteries tested here...
Within the app I am getting ~11.5 volts and it intermittently jumps to ~14.0. The headlights brighten and dim with the voltage, but the battery light is more intermittent.
I’ll get the batteries tested here...
Laughing Gas
Joined: Nov 2010
Posts: 1,159
Likes: 33
From: Utah
Each time (2x now) my battery light has flickered, a new alternator was the solution. Last go, I upgraded to a 6.0 alternator and added a heavy gauge ground from a mounting bolt to the frame and it's been solid since then which has been about 2 1/2 years now.
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Laughing Gas
Joined: Mar 2017
Posts: 833
Likes: 4
I stopped at NAPA and they swapped out my batteries under warranty... CCAs were not up to snuff (which is odd - the truck fired right up today at 15F)
The flickering problem persists.
Voltage at the alternator and both batteries reads the same - with the new batteries voltage now jumps between 12.4 and 14.4 in all three places. Battery light hasn't changed.
I'm going to order a new alternator from Amazon. Are all 6.0 alternators a direct fit? I was going to get the 140~ amp one as it might be nice when running the winch.
The flickering problem persists.
Voltage at the alternator and both batteries reads the same - with the new batteries voltage now jumps between 12.4 and 14.4 in all three places. Battery light hasn't changed.
I'm going to order a new alternator from Amazon. Are all 6.0 alternators a direct fit? I was going to get the 140~ amp one as it might be nice when running the winch.
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More Turbo
Joined: Apr 2008
Posts: 515
Likes: 6
From: North East Arkansas.
Battery light flickering. If all connections are tight, its the voltage regulator on the alternator. I bought a new one years ago at Autozone with a Life Time Warranty. When it went out, they swapped it out for a brand new one. No questions asked.
Fleet Mechanic
Joined: Jul 2010
Posts: 1,753
Likes: 34
From: Los Angeles, Ca.
AFAIK the 110 and 140 are the same externally. If you up the amperage you should also increase the charge wire size or add a second which is much easier, this will let you get full advantage of the higher output and not chance overheating the stock wire, especially when loading it with a winch or other extras.
I recently changed to the 6.0 Alt., I got it from my local rebuilder and he took my small one as the core without issue. I don't know if it's a 110 or 140. The 6.0 has a larger pulley so it'll turn slower, I considered swapping pullies but it works just fine so I like that it's turning a bit slower. Voltage during glow plugs on is higher and when they turn off it jumps to 14ish volts much faster than before. My stock alternator was screwed up so I don't know how the 6.0 with large pulley compares to a healthy stock one. I haven't added a secondary wire yet, guessing that'll help too.
I recently changed to the 6.0 Alt., I got it from my local rebuilder and he took my small one as the core without issue. I don't know if it's a 110 or 140. The 6.0 has a larger pulley so it'll turn slower, I considered swapping pullies but it works just fine so I like that it's turning a bit slower. Voltage during glow plugs on is higher and when they turn off it jumps to 14ish volts much faster than before. My stock alternator was screwed up so I don't know how the 6.0 with large pulley compares to a healthy stock one. I haven't added a secondary wire yet, guessing that'll help too.
Lead Driver
Joined: Dec 2006
Posts: 7,092
Likes: 145
From: San Diego, CA
Like '88 E-350 I kept the pulleys on that it came with and had no issues.
Banned
Joined: Dec 2018
Posts: 3,541
Likes: 458
Ran some tests this evening with Forscan and the headlights.
Within the app I am getting ~11.5 volts and it intermittently jumps to ~14.0. The headlights brighten and dim with the voltage, but the battery light is more intermittent.
I’ll get the batteries tested here...
Within the app I am getting ~11.5 volts and it intermittently jumps to ~14.0. The headlights brighten and dim with the voltage, but the battery light is more intermittent.
I’ll get the batteries tested here...
Hotshot
Joined: Mar 2014
Posts: 10,750
Likes: 1,065
From: Douglassville, PA
You know what a handy tool is for monitoring system voltage is one of those USB charger outlets with a digital voltage display (12.6, 14.4, etc). They are like $20-25 on Amazon. It is always within a tenth of the voltage reading on my EDGE insight with the ignition ON or motor running, but with the added benefit of being able to easily see the resting battery voltage with the system powered off.