When I purchased the 2005 Escalade, the previous owner had just replaced the alternator (I'm guessing it's a reman unit). However, I noticed that the voltage gauge goes up and down and the interior lights get brighter and dimmer at the same rate when at idle. Should I suspect this "new" alternator, or something else in the charging system? What diagnostic steps would the community recommend?
Alternator / Charging system diag
- Thread starter xdmtoter
- Start date
Cadillacmak
Well-Known Member
Start with the ground wires, pull them, clean connections and look for corrosion up the cable. Then do the same with the power cables. Check voltage at the battery, at the output on the alt. If your alt is putting out 14v and at the battery its 12v your battery could be getting weak or the cable in between is corroded. Voltage drop is caused from resistance, the more corrosion the higher resistance, the smaller the cable the higher resistance. If replacing a cable a new one, "tinned" copper had less resistance than straight copper. If you charge up your battery and everything is fine until it runs a bit, than the alt might not be able to keep up due to a problem with it. Some alts dont charge under a 1000 rpm, maybe check the part number and research that.
stutaeng
Well-Known Member
You don't have like 2500 watt sound system, now do you? It never hurts to ask because on these forums and in my experience, folks have said some stuff that's sounds pretty crazy, then after a lot of back-and-forth questions, turns out they leave some detail like that out. LOL
The good news is that on these trucks, 9.9999 times out of 10, charging issues are either the battery, the alternator or a wiring issue. Get those tested, as @Cadillacmak indicated. A few years ago the alternator on my 06 Suburban started failing. The voltage was simply lower and lower, down into the 10V range. A "new"/remanufactured starter and off I went...
The good news is that on these trucks, 9.9999 times out of 10, charging issues are either the battery, the alternator or a wiring issue. Get those tested, as @Cadillacmak indicated. A few years ago the alternator on my 06 Suburban started failing. The voltage was simply lower and lower, down into the 10V range. A "new"/remanufactured starter and off I went...
99Sierra2500
Well-Known Member
Winter always kills batteries too. I'd check everything like everyone mentions, and get some contact cleaner, and dielectric grease, and prepare to maybe buy an alternator, battery or both. They are super easy to change, not like some vehicles where it's buried.
AuroraGirl
Well-Known Member
BEHAVIOR IS NORMAL. 2005 half tons got RVC system, that behavior is normal. turn the headlights on manually, the voltage should go higher and stay there and no longer lope the brightness of the lights.
I took a quick vid with the headlights on and the fan running. I was hoping that the microphone would pick up the fan changing speed, but it's difficult to hear. Lights were pulsing and fan was changing speed at the same rate as the volt gauge moving.
drive.google.com
IMG_6064.MOV
drive.google.com
Similar threads
