Alternator overcharging??

[olznut]

Might be nothing but today while doing errands I noticed the volt meter on my 06 was sitting about 3/4 high on the gauge, which is still in the range, just a little on the high side imo. I'm not electriconically knowledgeable so is this a sign of something or is it ok?

 

[Alphasig112]

Might be nothing but today while doing errands I noticed the volt meter on my 06 was sitting about 3/4 high on the gauge, which is still in the range, just a little on the high side imo. I'm not electriconically knowledgeable so is this a sign of something or is it ok?

No. It is not an issue to worry about as long as it stays consistent. Normal range is normally 13.8-15.1 Volts. Mine charges 14.6 during winter and 14.1 summer. Gauge on the dash is wildly inaccurate and typically looks like I am charging at the top of the normal range.

 

[olznut]

Thanks, all I've noticed is when the heater comes on, it pulls it down to the low side then goes back to the middle but only recently has it gone to almost 3/4. Everything else is fine.

 

[Alphasig112]

I’ve got mine monitored on my tuner and have checked the accuracy with a volt meter at the battery. It is dead on accurate so mine will drop to 12.1 when the grid heater fires up and then go back to 14.something.

 

[Bob4x4]

On an 06 I would test batteries first,be aware some testers are better than others.The only way to test the batteries on a dual system is to isolate them first

 

[Alphasig112]

That’s at 14.4 volts.

 

[seafish]

While ambient temperature will effect voltage charging rates, as a precaution, you might want to check the voltage of EACH battery with the truck running with a digital voltmeter, as it IS possible for the ECM to overcharge one battery or the other if the one of them is going bad or if the crossover cable is going bad (fairly common occurrence) or even if there is a posse or dirty connection on one of the battery terminal or engine ground points. Better safe then sorry, as overcharging can and will eventually cause battery failure. Battery voltages in a dual battery system should be nearly equal to each other when checked with the engine running, anything different is indicative of a problem developing.

 

[cerberusiam]

View attachment 101862 That’s at 14.4 volts.

You have an issue in either the wiring or the ECM for it to read that high. ECM is seeing extremely high charge rates where your testing is not catching them. Anything that high on the gauge has always been a problem, about 1/2 way between 14 and the black mark just above your needle is what it should show after a heavy cold start then drop and run about 1/3 that range. You can't test voltage and assume everything is correct you need to get an amp draw on the charging wire to see if it maxing out amps.

 

[Alphasig112]

None of the gauges in the cluster read correctly. They are wildly in accurate. Tuner and manual gauges show more reliable data. Temp always show in excess of 200 degrees. Fuel will read full until the level is in need the of 10 gallons. Rpm shows 300 over actual. Sooo I’m inclined to not believe anything my gauge cluster says.

 

[Alphasig112]

My tuner is getting its information from the ECM same as the cluster. Just the tuner is showing actual numbers and not just a dial indicator.

 

[PWong]

My tuner is getting its information from the ECM same as the cluster. Just the tuner is showing actual numbers and not just a dial indicator.

What's the actual reading?
Post a number.
It should be 15V at around freezing ambient temp.
Your stock gauge read 15.5V to me and it's the driver side battery voltage. To me it's a bit too high.

 

[Alphasig112]

What's the actual reading?
Post a number.
It should be 15V at around freezing ambient temp.
Your stock gauge read 15.5V to me and it's the driver side battery voltage. To me it's a bit too high.

I agree. Actual is reading 14.6 cold. The gauge on my dash I think has a fault in it and this is what it always looks like. Never returns to bottom. #ad


With just the key on not running it sits centered#ad

 

[Alphasig112]

That second picture is at a confirmed 12.6 volts battery power only. Same at both batteries independently tested.

 

[ntsqd]

Is that isolated batteries that have sat unused (no charge or discharge) for at least a couple of hours? If not then the voltage readings are not true.

 

[Alphasig112]

Is that isolated batteries that have sat unused (no charge or discharge) for at least a couple of hours? If not then the voltage readings are not true.

Yeah that’s after a few days of sitting.

 

[ntsqd]

Sitting connected or isolated? It's possibly splitting hairs, but sitting connected can cause battery activity if there is any connection resistance. BT, DT with paired batteries killing them selves over the seemingly insignificant resistance from one head bolt on the driver's side of an SBC to a head bolt on the pass side of the same engine.

 

[Alphasig112]

Sitting connected or isolated? It's possibly splitting hairs, but sitting connected can cause battery activity if there is any connection resistance. BT, DT with paired batteries killing them selves over the seemingly insignificant resistance from one head bolt on the driver's side of an SBC to a head bolt on the pass side of the same engine.

Isolated. Batteries are 2 months old. I just think my gauge on the dash is off. Like I said it never returns to 0 and shows 14 on just battery power alone.

 

[Bob4x4]

Gauges have not returned to 0 for many years on dodge products

 

[PWong]

That second picture is at a confirmed 12.6 volts battery power only. Same at both batteries independently tested.

Your gauge is a big liar, 1.5V off.

 

[cerberusiam]

All my gauges go onto the low peg when key is off. Might try unplugging the cluster and see if that drops them to the pegs. If it does there are issues in the electrical system, if not cluster is bad which is not unheard of on an 06.