Ughhh.. Voltage Issue 08' Yuk Denali..

[Denali_WA]

About a two months ago my Yuk Denali was having issues charging & maintaining a charge. So I went combing through the threads on here looking for ideas to to correct the issue. First, I replaced the battery with a better battery. The issue still was existing and i was noticing that my voltage was dropping from 14v to 12v depending on the engine load. Then I decided to upgrade the grounding and main power distribution wires to 0awg, known as the Big 3. After that mod I was still having the same issue with the voltage dropping. Lastly (which i thought would be the fix), I replaced the factory alternator with a high output, 250 amp alt. And still having the same issue I am at a loss now as to what could be causing the voltage issue.. Anyone have any ideas??

 

[yukon702]

I'm having the exact same problem. I have an aftermarket stereo system with amplifiers in the back and the batteries up front in the engine compartment.

Under load the voltage drops to almost 12 volts. It has to do with the grounding and the resistance of the batteries being so far away from the amps. This weekend I'm going to put one of the batteries closer to the amps in the back. A guy had the same problem with his Tahoe and he said it cured the voltage drop

 

[Hayabusaboi06]

I'm in that same boat. Did b3, 2xs d3400's under the hood and still in the 12 range. Took my 15's out and 2 10's in cause my volts won't stay high enough. Still drops with 10's. Lost man

 

[NathanJax]

You are aware the alternators will turn off and not charge at times it doesn't need to charge... It's another stupid way they try to save power/energy/mpg.

 

[sumo]

You are aware the alternators will turn off and not charge at times it doesn't need to charge... It's another stupid way they try to save power/energy/mpg.

Yea depending on the load the bcm will command the alternator on how much to put out. However i believe in the owners manual to says if you have the tow buttton on the alternators it will put out more to charge trailer batteries

 

[Speck]

Denali_WA where are you located in the PNW? I was having a similar issue with my 08 Denali and found out my power distribution block on the firewall was the culprit. The fuse was corroded and arcing to the firewall and did not "pop" like it is designed to do. Because of the resistance and power fluctuations, it was giving me all sorts of problems with power drops and loss of all power at times.

I recently took mine to Sunset Chevrolet in Sumner, WA and they were able to find the problem with my distribution block (that was the second one that I've had replaced now) and they also discovered I had seperation in my power wires from the crimps and terminals. They soldered the wires to be solid and replaced the terminal and I haven't had a lick of problem since.

My guess on your situation would be to check the power distribution block since you have already replaced your power and ground wires. Hopefully that will be the fix for you...

Joe

 

[Denali_WA]

Denali_WA where are you located in the PNW? I was having a similar issue with my 08 Denali and found out my power distribution block on the firewall was the culprit. The fuse was corroded and arcing to the firewall and did not "pop" like it is designed to do. Because of the resistance and power fluctuations, it was giving me all sorts of problems with power drops and loss of all power at times.

I recently took mine to Sunset Chevrolet in Sumner, WA and they were able to find the problem with my distribution block (that was the second one that I've had replaced now) and they also discovered I had seperation in my power wires from the crimps and terminals. They soldered the wires to be solid and replaced the terminal and I haven't had a lick of problem since.

My guess on your situation would be to check the power distribution block since you have already replaced your power and ground wires. Hopefully that will be the fix for you...

Joe

I had not thought of that, that is a really good call! I actually bought my denali from Sunset Chevy, I live just up the hill from there in Puyallup. I am going to take a look at the distribution block when i get home, hopefully its a quick fix. Thanks again for the advise!!

 

[ccapehartusarmyINF.(ret)]

just a tip
when ever yer getting sudden voltage drops like that go through all yer grounds and positive terminals check them for high resistance with a multi meter especially check all yer grounds
high resistance=voltage drop make sure everythings nice and tight and getting a good connection i was able to get 14 volts all the way back at my amp terminals

 

[Speck]

I had not thought of that, that is a really good call! I actually bought my denali from Sunset Chevy, I live just up the hill from there in Puyallup. I am going to take a look at the distribution block when i get home, hopefully its a quick fix. Thanks again for the advise!!

Nice! I'm just down the road in Olympia. We'll have to see how many other locals are on here and meet up sometime. The service tech was Ian there at Sunset who I've been working with and have been very happy.

Joe