2004 Sierra Electrical issues

yz2009 · April 9, 2013

Ive got a 2004 Sierra 1500 LS with some small electrical issues. 115k miles.

About 2 years ago problem 1 started.

#1 Sometimes when using the truck the DIC display cycles between languages (English, French, Spanish) and cycles between the 3 modes (odometer, hours, and trip) without pressing any buttons. It doesnt always do it and sometimes it stops. Also sometimes it resets the trip to 0 miles. Again it doesnt always do it, its completely random.

Problem 2 started about a month ago

#2 Within the past month this has happened twice. I start the truck and the battery light comes on and the DIC says battery not charging. Upon restart the battery light goes away. When this light is on the battery is deffinitly not charging. If the lights are on and the heat on the battery voltage goes down to about 12.5v and slowly drains. LIke i said upon restart the light goes away and the battery charges like normal.

Any insight would be appriciated.

Bad Bowtie2 · April 9, 2013

Clean & recheck you battery cables, and grounding points.

Have your alternator loadtested at your favorite autoparts store (free service). It could have a faulty diode inside?

yz2009 · April 9, 2013

I guess i should have mentioned in the first post that i have checked all battery connections and grounds. Everything is tight and clean at the battery, alternator, and grounding locations

txab · April 9, 2013

Then also load test the battery and check alternator output.

bossier62guy · April 10, 2013

Regarding problem 2.....are you basing your assumptions on the IPC or did you actually put a multimeter on the battery terminals to verify that you indeed are in a "no charge" state? Since you've had DIC problems for 2 years and all of the DIC components (w/ the exception of the steering wheel controls) seem to be part of the IPC....do you see where this is going?

First I'd do as the other guys suggested and have the battery/alternator tested....if they're good we'll continue on.

txab · April 10, 2013

Also check the cable condition. Make sure it's going bad internally

yz2009 · April 11, 2013

the battery is new, i can get the alternator checked this weekend though.

I did not check the actually battery voltage with a multimeter when the no charge light was on. However under normal operating conditions the voltage gauge reads just over 14 volts. When the no charge light came in it was just under 14 with the headlights off. When i turned the headlight on the voltage read about 13 and with the heater on it was just under 13. Again i didn't put a multimeter on the battery but every time i turned something on the battery gauge on the dash would go down.

My suspicion is there is something internally wrong with the alternator Unless it gets worse im not going to worry about it seeing as the problem solves itself after i restart the truck. My bigger question is #1 and why the DIC would cycle through languages and reset the trip milage.