jQuery not supported.



Charging Issue

Charging Issue

Postby trevner [OP] » Oct 26 2012, 4:07am

Hey all new to the forum.

I have a 2007 Silverado Classic 1500 4x4 5.3L. Recently I have been having issues with the battery going dead after the truck isn't drove for a few days. I charged the battery and load tested it and it came back "Good". Got the truck running and used a DMM and checked the alternator output which was 16+ volts which seemed really high. Also checked for a parasitic drain with DMM on negative post to negative cable. DMM showed 5ma which doesn't seem like an issue to me. I went ahead and replaced the alternator and battery at the same time. I noticed the new alternator has a slightly larger pulley than the old alternator. Now with the truck running the alternator is putting out 14.5-15.3 volts. I took the truck for a drive and once it reached normal operating temp the voltage dropped and lights went extremely dim while stopped at a red light. After a couple seconds of low voltage the light became bright and voltage gauge went back to 14.5 volts. I'm unsure as to what is going on. Is it possible that the slightly larger pulley is causing this voltage drop at a stand still? It never did this before swapping alternators. Also, if the tensioner is getting weak could the belt be slipping also causing low voltage at a stand still? Is there some grounds i should have a look at? If so where abouts are they located? Any help would be greatly appreciated!

Trevor
Original Poster
trevner
Newbie
Newbie
Posts: 3
Topics: 1
Joined: Oct 26 2012, 3:43am
Years of membership: 1 year of membership
Location: Canada
Year: 2007
Make/Model: Chevrolet Silverado
Extra Info: 1500 Classic 4x4
Group Membership:
Registered users

Re: Charging Issue

Postby ASTE25 » Oct 27 2012, 6:31am

I would suspect a parasitic drain and not a problem with the charging system. I think you can Google a search and find out how to find the source of the drain and how to fix it.
Jordan
ASTE25
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 10933
Topics: 19
Images: 21
Joined: Jan 03 2011, 6:37am
Years of membership: 3 years of membership3 years of membership3 years of membership
Location: New Market, Alabama
Year: 2015
Make/Model: ...Not an owner
Group Membership:
Automotive Technicians
Member Extraordinaire
Registered users

Charging Issue

Postby Machster69 » Oct 27 2012, 12:46pm

5ma is not considered a draw. Your sure it was just the a/c surge that dimmed the lights for that second? And you seem to have all the right ideas already, tensioner, grounds etc... The have several ground straps on the motor, also check fuses to make sure none are lose
Machster69
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 7966
Topics: 105
Images: 79
Joined: Feb 16 2012, 3:03pm
Years of membership: 2 years of membership2 years of membership
Location: Baton Rouge
Year: 2010
Make/Model: GMC Sierra
Extra Info: 5.3 SLE 2wd
Group Membership:
How-to Authors
SilveradoSierra Guru
Registered users

Re: Charging Issue

Postby HartskiHartski is online! » Oct 27 2012, 1:17pm

I'd check the chassis ground, first.
in omnia paratus
HartskiHartski is online!
It's my Birthday today!
Shifting into Fourth Gear [L3]
Shifting into Fourth Gear [L3]
Posts: 1488
Topics: 6
Images: 23
Joined: Jun 24 2010, 9:25pm
Years of membership: 4 years of membership4 years of membership4 years of membership4 years of membership
Location: Iowa
Year: 2010
Make/Model: Chevrolet Silverado
Extra Info: LTZ Z71
Group Membership:
Registered users

Re: Charging Issue

Postby trevner [OP] » Oct 27 2012, 5:02pm

Thanks all for the replies. I'm positive it wasn't the A/C causing the surge. A/C and climate control was turned off as well as the radio. Only accessory that was on at the time was the headlights. It did it numerous times at different red lights. I also checked all fuses for continuity and looseness, all were good. I removed several ground wires and cleaned the contacts as well as checked the wires for resistance. All seemed to be good. I started up the truck and metered the alternator output afterwards and it was at 15.5V (with no accessories on) until it reached normal operating temp then it dropped to 14.6V (is this normal?). I took it for a drive and everything seemed to be back to normal. No more surging or dimming headlights. I'll check the voltage on the battery today before i try to start it and see if it has dropped over night. If it has dropped below 12V i am going to disconnect the aftermarket command start. I heard they can cause some draining issues over time. I'm unsure of how many ground wires there are but here are the ones i found, cleaned and checked resistance on.

-Ground wire from battery to engine block
-Ground wire from battery to front bumper
-Ground wire from engine block to fire wall
-Ground wire from fire wall to hood
-Contacts in junction box from alternator to battery and starter.

Anyone know if there is any more grounds i should look at?

Thanks again for all the help. Will let you know what i find out today.


Trevor
Original Poster
trevner
Newbie
Newbie
Posts: 3
Topics: 1
Joined: Oct 26 2012, 3:43am
Years of membership: 1 year of membership
Location: Canada
Year: 2007
Make/Model: Chevrolet Silverado
Extra Info: 1500 Classic 4x4
Group Membership:
Registered users

Charging Issue

Postby Machster69 » Oct 27 2012, 6:34pm

Well if the battery does drop, do a draw test and isolate that circuit to see if its the culprit
Machster69
Shifting into Sixth Gear! [L3]
Shifting into Sixth Gear! [L3]
Posts: 7966
Topics: 105
Images: 79
Joined: Feb 16 2012, 3:03pm
Years of membership: 2 years of membership2 years of membership
Location: Baton Rouge
Year: 2010
Make/Model: GMC Sierra
Extra Info: 5.3 SLE 2wd
Group Membership:
How-to Authors
SilveradoSierra Guru
Registered users

Re: Charging Issue

Postby alexw » Mar 15 2013, 8:34pm

Did you ever find the problem?
alexw
Newbie
Newbie
Posts: 1
Joined: Mar 15 2013, 8:29pm
Years of membership: 1 year of membership
Location: NE IA
Year: 2004
Make/Model: GMC Sierra
Group Membership:
Registered users

Re: Charging Issue

Postby trevner [OP] » Mar 16 2013, 8:56pm

Once i cleaned all the ground contacts everything seemed to go back to normal. I havent had a problem since. The only thing i notice is slightly higher voltage reading on my gauge. Use to sit around 14.5 volts and now it sits around 15.5 volts.
Original Poster
trevner
Newbie
Newbie
Posts: 3
Topics: 1
Joined: Oct 26 2012, 3:43am
Years of membership: 1 year of membership
Location: Canada
Year: 2007
Make/Model: Chevrolet Silverado
Extra Info: 1500 Classic 4x4
Group Membership:
Registered users

Return to Electrical

 

  • Similar topics
    Replies
    Views
    Last post
  • Over charging battery
    by rewinings » Jan 07 2011, 4:38am
    3 Replies
    1990 Views
    User avatar
    Last post by lzn197 View the latest post
    Jan 13 2011, 1:22am
  • 6 Replies
    75 Views
    Last post by SilveradoSierra.com View the latest post
    Oct 02 2014, 3:20am
  • Charging system
    Headlights dim
    by matheny9 » Sep 06 2012, 2:32pm
    3 Replies
    808 Views
    Last post by Machster69 View the latest post
    Sep 06 2012, 2:37pm
  • Charging system
    Battery low charge,
    by MrJWStanley » Sep 07 2013, 7:26pm
    2 Replies
    590 Views
    User avatar
    Last post by SilverSurfer View the latest post
    Sep 08 2013, 2:55am
  • Charging problem?
    by bushwood » Sep 25 2013, 9:46pm
    2 Replies
    292 Views
    Last post by bushwood View the latest post
    Sep 25 2013, 11:13pm
  • CHARGING SYSTEM
    ALT DOESNT CHARGE TILL 25 SECONDS RUNNING
    by kevin46-4x » Feb 25 2014, 5:36pm
    0 Replies
    189 Views
    Last post by kevin46-4x View the latest post
    Feb 25 2014, 5:36pm

Common search terms

back problem check charging help issue anyone today light thing getting first right think thanks front same make still engine

It is currently Oct 02 2014, 3:20am

  • Sponsor
Login  •  Register
SHOP TALK (Live Chat)
Electrical Forum
ElectricalDiscussion specific to electric components of trucks. Category for alternators or batteries, starters and ignition parts, anything 12v and electrical issue like fuses, circuitry, wire, terminals, switches, connectors, bulbs, relays, and wiring. Voltage and amperage diagnosis.
To create a new topic in Electrical, click this button:
Previous topic Next topic
Sitewide News Sitemaps & Feeds

Who is online

Users browsing this forum: No registered users and 13 guests