Odd Electrical Issues

[bbro44]

Hey y'all,

I’m dealing with an extremely odd, inconsistent electrical issue and could use some advice.

First, a bit of context: I’ve done a few mods to my truck, including some electrical work. I always try to do things right, though we all know how projects can go sometimes! On August 7th, I started replacing the radio (Boss Audio BE7ACP) and the four door speakers (MTX Terminator6s), and finished up on the 22nd. On August 25th, I replaced my corroded battery terminals. Around the same time, on the 24th, I began installing running board lights, but rewired them a few times (and am still not done) to get them working the way I want. Then on September 3rd, I installed a light bar, but I think I accidentally closed the hood on the relay, causing the light bar to stay on. I rewired that multiple times too, but couldn’t get it to work right. I ended up getting the light to turn off and left it at that for now—I just received new relays and plan to set it up according to the instruction manual.

Now, onto the issue. On August 23rd, I went to start my truck and the dash went completely haywire—lights flashing, indicators spinning, etc.—and it wouldn’t turn over, so I had to jump it. Later that day, I had to jump it again. Strangely, about an hour after the second jump, it started up like nothing had happened. Fast forward to today, and a similar thing occurred. The dash went crazy, the truck wouldn’t start, and I had to jump it. After a few hours, it started normally, but while driving, the electrical system went haywire again—AC stopped working, windows wouldn’t roll down, turn signals didn’t work (but hazards did), and the airbag light went off. Then, mid-drive, the check engine light came back on (I have some ongoing, unrelated codes). When I got home, I turned the truck off and back on, and suddenly everything was back to normal.

Another thing I’ve noticed: the only sign this is going to happen is that the truck won’t lock via the key fob. On August 23rd, before the issues began, I drove somewhere, parked for a couple of hours, came back, started it fine, drove for 30 minutes, parked again, and that’s when it wouldn’t start and I needed a jump. Today, I drove for 20 minutes, parked for 30, drove another 25 minutes, parked for a couple of hours, and again it wouldn’t start and needed a jump.

Also, I’ve had weird issues with the driver-side window switches twice. The first time was on the 23rd: after jumping the truck, I rolled the windows up, and when they reached the top, the truck died as if I turned off the key. The second time was while testing the light bar: I hit the switch to roll the windows up, and the dash lit up like a Christmas tree again. No other symptoms that time, but still very strange.

Any ideas on what could be causing this?

Thanks

 

[bbro44]

I should also mention that the previous owner claimed to have changed the battery (EverStart Maxx 65) and alternator within the 2024 calendar year.

 

[BossHogg]

This has the signature of a battery with a single-cell misbehaving. First, rule out the alternator, check the battery voltage while the engine is running, and measure the voltage at both the battery terminal and the battery post to prevent getting fooled by a battery terminal connection issue. You should see a voltage in the upper 13 to low 14-volt range with the engine running and mid 12 volts with the engine off.

To see if a cell is misbehaving, you would need to set up a DVM that can record minimum values. A few years ago I had a new battery installed by my local wholesale club. On the drive home, the engine stalled. I cycled the ignition a few times and then the engine started. I drove back to the club and they tested the battery and told me the battery tested OK. I did make it home, the 5 or so miles, but with a couple of stalls along the way.

When I got home, I set up my DVM to monitor the battery and record minimal voltages. The next morning, the DVM showed the battery voltage dropping below 6 volts. Curious, I just happened to have a data recorder, so I set up the recorder to monitor the battery. The next day, the graph showed several periods where the battery voltage would drop for several minutes and then go back to its typical potential.

I gave this info to the tech at the wholesale club and he told me it is very rare to see this but one cell in the battery is bad. Installation of a new battery proved the tech was correct.

The moral of the story is just because something is new doesn't mean it works correctly. I never forgot this and I never got burned again. For example, my 2015 DIC told me I needed to replace the FOB's battery, so I stopped and picked up a new 2032 coin cell. When I got home and pulled the FOB apart to replace the coin cell, I tested the new battery's voltage and surprisingly, it read low. Any reasonable person would assume there is something else wrong and possibly spend a couple hundred bucks for a dealer diagnostics fee.

 

[bbro44]

Wow, I've never heard of that- ill have to do a bit of digging and get back to you with what I find. Thank you! It makes me feel a little better knowing that it may not have been something that I wired wrong haha.

This has the signature of a battery with a single-cell misbehaving. First, rule out the alternator, check the battery voltage while the engine is running, and measure the voltage at both the battery terminal and the battery post to prevent getting fooled by a battery terminal connection issue. You should see a voltage in the upper 13 to low 14-volt range with the engine running and mid 12 volts with the engine off.

To see if a cell is misbehaving, you would need to set up a DVM that can record minimum values. A few years ago I had a new battery installed by my local wholesale club. On the drive home, the engine stalled. I cycled the ignition a few times and then the engine started. I drove back to the club and they tested the battery and told me the battery tested OK. I did make it home, the 5 or so miles, but with a couple of stalls along the way.

When I got home, I set up my DVM to monitor the battery and record minimal voltages. The next morning, the DVM showed the battery voltage dropping below 6 volts. Curious, I just happened to have a data recorder, so I set up the recorder to monitor the battery. The next day, the graph showed several periods where the battery voltage would drop for several minutes and then go back to its typical potential.

I gave this info to the tech at the wholesale club and he told me it is very rare to see this but one cell in the battery is bad. Installation of a new battery proved the tech was correct.

The moral of the story is just because something is new doesn't mean it works correctly. I never forgot this and I never got burned again. For example, my 2015 DIC told me I needed to replace the FOB's battery, so I stopped and picked up a new 2032 coin cell. When I got home and pulled the FOB apart to replace the coin cell, I tested the new battery's voltage and surprisingly, it read low. Any reasonable person would assume there is something else wrong and possibly spend a couple hundred bucks for a dealer diagnostics fee.

 

[RamDiver]

While that's one solution to prove a flakey cell in the battery, I'm more of an instant gratification type of guy.

I own an old-style toaster-type battery load tester. In 6-10 seconds, depending on the tester, it will inform you of the available cranking amps. Also, most flakey cells will show under the heavy load of the tester.

HarbourFreight sells these load testers for $20.

100 Amp, 6/12V Battery Load Tester

Amazing deals on this 100 Amp 6/12V Battery Load Tester at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

If your battery connections, ground connections, or starter motor wiring are loose or corroded, intermittent starting should be expected so, inspect, clean and tighten all connections first.

There are great YouTube videos on troubleshooting and verify your main ground wire is adequate. That will also create irregular electrical and starting features.

.

 

[bbro44]

I may pick one of those up, but I'd imagine somewhere like autozone can also test that.

While that's one solution to prove a flakey cell in the battery, I'm more of an instant gratification type of guy.

I own an old-style toaster-type battery load tester. In 6-10 seconds, depending on the tester, it will inform you of the available cranking amps. Also, most flakey cells will show under the heavy load of the tester.

HarbourFreight sells these load testers for $20.

100 Amp, 6/12V Battery Load Tester

Amazing deals on this 100 Amp 6/12V Battery Load Tester at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

If your battery connections, ground connections, or starter motor wiring are loose or corroded, intermittent starting should be expected so, inspect, clean and tighten all connections first.

There are great YouTube videos on troubleshooting and verify your main ground wire is adequate. That will also create irregular electrical and starting features.

.

 

[bbro44]

Also, here's a video on what it does- it doesn't always look like this, but it's usually similar. Sometimes the dash lights up, sometimes it just flutters, etc.

It fluttered like that a couple times before cranking up in the video.

 

[RamDiver]

I may pick one of those up, but I'd imagine somewhere like autozone can also test that.

Most auto parts stores will test your alternator and battery for no charge. A good test for the alternator, not so much for batteries.

The problem with them performing a battery load test is the vast majority of them use a digital-type load tester. They are prone to false positives, especially for flakey cell problems.

It does not apply a load and calculates the CCA using an algorithm based on the battery's reactance properties.

Very often, a flakey cell will remain hidden until a significant load is applied.

Also, here's a video on what it does- it doesn't always look like this, but it's usually similar. Sometimes the dash lights up, sometimes it just flutters, etc.

It fluttered like that a couple times before cranking up in the video.

I must be missing something, all I see is the usual lamp test before starting. My speedo doesn't pin during starts but I don't think that is too unusual.

What exactly should we be looking for in this video?

A flakey battery cell causes havoc on our trucks and often displays CELs, various system faults, and a myriad of different types of light shows.

Whenever we see multiple unrelated electronic system faults or tell-tale signs relating to power, the common denominator is most often the power source.

Either the battery or it's connection are typically the culpret creating grief. Our trucks are rolling microcomputers and very sensitive to power related problems.

.

 

[bbro44]

Most auto parts stores will test your alternator and battery for no charge. A good test for the alternator, not so much for batteries.

The problem with them performing a battery load test is the vast majority of them use a digital-type load tester. They are prone to false positives, especially for flakey cell problems.

It does not apply a load and calculates the CCA using an algorithm based on the battery's reactance properties.

Very often, a flakey cell will remain hidden until a significant load is applied.

Okay- you said the harbor freight load tester will find any wacky cells? I brought it to an autozone- the guy said the tester should see flakey cells and it did not, but who knows if it truly can see them.

I must be missing something, all I see is the usual lamp test before starting. My speedo doesn't pin during starts but I don't think that is too unusual.

What exactly should we be looking for in this video?

This video isnt a great example of it. When I turn the key, the screen flickers, some other lights flicker, dials move a smidge, and it doesn't start. Usually it's much more pronounced than this time- if it happens again, I'll try to get a better video. Usually the whole dash lights up.

The best way I can describe what it does is fluttering. The screen flutters, the ignition sorta flutters, etc.

It's a difficult problem to explain- like I said, if it happens again, I'll try to get a better video.

 

[RamDiver]

Okay- you said the harbor freight load tester will find any wacky cells? I brought it to an autozone- the guy said the tester should see flakey cells and it did not, but who knows if it truly can see them.

I specifically identified a toaster-style load tester to be more likely to identify a flakey cell (as linked in post 5) and mentioned that the digital-type testers used at most locations would not.

If you had AutoZone test your battery, AFAIK, most locations will use a digital tester. A digital tester is close to useless while trying to find a failing cell because they don't create a high load as the toaster does.

So, did they use a digital or toaster battery load tester?

Also, did you have them test the alternator?

This video isnt a great example of it. When I turn the key, the screen flickers, some other lights flicker, dials move a smidge, and it doesn't start. Usually it's much more pronounced than this time- if it happens again, I'll try to get a better video. Usually the whole dash lights up.

The best way I can describe what it does is fluttering. The screen flutters, the ignition sorta flutters, etc.

It's a difficult problem to explain- like I said, if it happens again, I'll try to get a better video.

This is just like going to the dentist with a sore tooth.

Were you able to clean & inspect the battery connections and both ends of the negative battery wire?

This is the best $3 you can spend on battery maintenance tools.
It's quick & easy and cleans up posts and clamps perfectly.

https://www.harborfreight.com/automotive/battery-tools-accessories/battery-terminal-cleaner-94450.html

.

 

[Towbar2]

I should also mention that the previous owner claimed to have changed the battery (EverStart Maxx 65) and alternator within the 2024 calendar year.

Try turning the key to the "on" position (but don't start it. Wait 10-12 minutes (with the key on). Then start it. I think the safe-fail circuit attached (in the computer anti-theft) needs to be reset.

 

[bbro44]

So, did they use a digital or toaster battery load tester?

Digital- I only ask because he specifically said they can normally see single cells misbehaving with it. I'll pick up a waffle soon. They did not test the alternator, but I know it charges while driving (I have an odb2 that reads out things like voltage, and I can see it change).

Were you able to clean & inspect the battery connections and both ends of the negative battery wire?

I replaced the battery terminals a few weeks ago, and when you mentioned that I looked... I've got a fair bit of corrosion on one side of the negative terminal clamp screw. Odd that it's corroded already after a couple weeks?

 

[bbro44]

You think that's causing these issues? Worth a shot I suppose

Try turning the key to the "on" position (but don't start it. Wait 10-12 minutes (with the key on). Then start it. I think the safe-fail circuit attached (in the computer anti-theft) needs to be reset.

 

[bbro44]

It's happened a few times since. I'm going to get the battery replaced this week.

 

[RamDiver]

Digital- I only ask because he specifically said they can normally see single cells misbehaving with it. I'll pick up a waffle soon. They did not test the alternator, but I know it charges while driving (I have an odb2 that reads out things like voltage, and I can see it change).

Unfortunately, your AutoZone guy is not correct. There are many individuals who will argue that digital-type battery load testers are the greatest, especially those who have invested $ to buy one.

The digital testers periodically produce false positives because they don't supply a sufficient load to stress flakey cells.

Most users don't understand how the testers function and arrive at a pass or fail result, maybe if they took the time to research the topic, they would understand the short-comings.

There's an excellent technical article available on the subject at BatteryUniversity.com if you're interested.

I replaced the battery terminals a few weeks ago, and when you mentioned that I looked... I've got a fair bit of corrosion on one side of the negative terminal clamp screw. Odd that it's corroded already after a couple weeks?

Rapid corrosion of a battery terminal is typically a sign of the post or clamp not clean and/or torqued properly.

The post/clamp cleaner I linked above is the supreme tool for cleaning posts/clamps and at a whopping cost of $3, I can't see why anyone would choose another method.

It's happened a few times since. I'm going to get the battery replaced this week.

You could gamble that the battery has a problem, chances are, that it has a flakey cell. My having worked in electronics for most of my life, my brain will not allow me to jump to any conclusions without a proper diagnosis.

Again, the correct tool for this job is a toaster-style battery load tester as linked above. If you're feeling lucky, take the parts cannon approach, save the $20 and replace the battery.

It sure would suck if luck isn't on your side.

.

 

[bbro44]

Unfortunately, your AutoZone guy is not correct. There are many individuals who will argue that digital-type battery load testers are the greatest, especially those who have invested $ to buy one.

The digital testers periodically produce false positives because they don't supply a sufficient load to stress flakey cells.

Most users don't understand how the testers function and arrive at a pass or fail result, maybe if they took the time to research the topic, they would understand the short-comings.

There's an excellent technical article available on the subject at BatteryUniversity.com if you're interested.




Rapid corrosion of a battery terminal is typically a sign of the post or clamp not clean and/or torqued properly.

The post/clamp cleaner I linked above is the supreme tool for cleaning posts/clamps and at a whopping cost of $3, I can't see why anyone would choose another method.




You could gamble that the battery has a problem, chances are, that it has a flakey cell. My having worked in electronics for most of my life, my brain will not allow me to jump to any conclusions without a proper diagnosis.

Again, the correct tool for this job is a toaster-style battery load tester as linked above. If you're feeling lucky, take the parts cannon approach, save the $20 and replace the battery.

It sure would suck if luck isn't on your side.

.

I mean... either the battery is the problem, I replace it, and the issue doesn't happen again, or the battery isn't the problem and the tester has no use. It would confirm that the battery is the problem, but so would it not happening again- and it's cheaper .

 

[bbro44]

I'll make sure my battery terminals are clamped tight and cleaned.