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Dead battery

Rickyrocket

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For those that have had this problem what was the final solution with the vacuum pump running problem?
 

Sniper75

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My battery is dead I had been putting the Halo jumper too it for 2 days and got tired of doing that so I put in a new Optima Red Top in it. The next morning truck would not start, battery completely drained. Took it to dealership. After 4 days they said that the diagnostics didn't show anything wrong with truck but the OEM battery showed a bad cell in it. I asked about the new Optima battery, and they said that I could have left something on so it drained. They put in a new OEM battery and said it was ready to be picked up, so I will see if this one will make it till the end of the week
 

HSKR R/T

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My battery is dead I had been putting the Halo jumper too it for 2 days and got tired of doing that so I put in a new Optima Red Top in it. The next morning truck would not start, battery completely drained. Took it to dealership. After 4 days they said that the diagnostics didn't show anything wrong with truck but the OEM battery showed a bad cell in it. I asked about the new Optima battery, and they said that I could have left something on so it drained. They put in a new OEM battery and said it was ready to be picked up, so I will see if this one will make it till the end of the week
Optima quality has gone to crap. You pay more for the name built when it was its own company before it was bought by Johnson Controls.
 

DannyMc

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For those that have had this problem what was the final solution with the vacuum pump running problem?
I’m interested in the solution as well. I found vacuum pump would run as soon as I connected jump box when battery died overnight. Took it in. dealer said pump tests OK. Truck is still in the shop (over 3 weeks) and dealer can’t isolate the parasitic draw. They say truck has 53 modules and they have to do the test when it decides to “act up”. Since Christmas it’s had 2 new batteries, a BCM, and nearly 7 weeks in the shop.
 

Sniper75

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Wow that's a long time. When I picked up my truck from the dealership I noticed the voltage was at 14.5 (I hope that is normal) when I started it up. I drove off and it started fluctuating 14.4,14.5 then to 14.3, 14.4 . This morning it was at 14.3 when I got to work it was at 14.2. Now after work when i got home at 3pm it is at 14.0 .went out and it's been like that till I got home at 8pm. So I don't know what is going on. If anyone can tell me what my voltage should be at when truck is running
 

HSKR R/T

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Wow that's a long time. When I picked up my truck from the dealership I noticed the voltage was at 14.5 (I hope that is normal) when I started it up. I drove off and it started fluctuating 14.4,14.5 then to 14.3, 14.4 . This morning it was at 14.3 when I got to work it was at 14.2. Now after work when i got home at 3pm it is at 14.0 .went out and it's been like that till I got home at 8pm. So I don't know what is going on. If anyone can tell me what my voltage should be at when truck is running
That sounds right for voltage. Was flipping through the screens yesterday on my drive and mine was charging at 14.3 cruising at 80mph
 

Sniper75

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Awesome I appreciate the info. I will keep an eye on it for now on.
 

23RAM

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Wow that's a long time. When I picked up my truck from the dealership I noticed the voltage was at 14.5 (I hope that is normal) when I started it up. I drove off and it started fluctuating 14.4,14.5 then to 14.3, 14.4 . This morning it was at 14.3 when I got to work it was at 14.2. Now after work when i got home at 3pm it is at 14.0 .went out and it's been like that till I got home at 8pm. So I don't know what is going on. If anyone can tell me what my voltage should be at when truck is running
I haven't monitored my battery voltage too much as the truck is brand new, but typically the resting voltage of a good freshly charged regular lead-acid battery is 12.6-12.7v and for AGM it's 12.9-13.2v. It can vary a little between battery types and manufacturers, but it should be around those numbers.

But when you start the truck and the engine is running the voltage should almost instantly rise to about 14.4v as that is the typical charging voltage for 12v systems. It might fluctuate a bit 14.2-14.6v when using windshield wipers or stop and go traffic, but should stay around 14.4v while the engine is running as the alternator will run the electronics and keep the battery charged until you shut off the engine. I have a longer drive to make on Saturday and will keep an eye on it for the duration to see how it reacts, but I expect it to follow the typical pattern.

I would be slightly concerned to see 14.0v when the engine is running...that to me sounds like the alternator's regulator circuit is faulty, or the battery has a bad cell and it's having a hard time managing the charging voltage.

Also contrary to what marketing campaigns would have you believe about car batteries, a properly maintained lead-acid starting battery in a daily driver vehicle should last for 10 years or more. Unless you run it down cranking tunes, using lights for hours, accessories on, letting it sit for weeks unused, or heavy draws like winching, etc., which will greatly reduce the capacity of the battery. But if all you do is drive the vehicle for regular transportation, it should last for many years. I've never changed a car battery unless the alternator failed. Current SUV is 10 years old, previous car was 8 years old, and both still had the factory battery in them. Both were regular daily drivers and never had a weak or dead battery situation.

But one thing I've always done since I had my first car, was a trick my dad taught me (he was an RAF plane engine mechanic who later became an EE and did electronics repair) - put petroleum jelly (Vaseline) on the positive and negative terminals to prevent corrosion and reduce electron loss. Today you can buy some insulating grease for the same purpose but Vaseline does the same job for free as most families with kids have a jar in the house already. Just clean it off if it gets dirty and re-apply. A thin even layer all around the terminal post and connector is all you need, apply with a very small paintbrush. The battery in our 10 year old SUV looks like new and although it has weakened a bit over time, it still cranks strong in -40 winters.
 

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