I have a 03 gmc.6.0 replaced batt. after checking charg with vat 40. alt. is good still get dim lights at idle
Amp. ga. goes to 9-10 then works back to 14 + When under accelleration charging is 14. Heater is on, radio on, lights on, ocasionaly have heater on driver seat for a few minutes, Purchased a 875cca. batt. on sat. 12/8/07 with dual posts. Mounts with side posts which are clean. Does not draw down at any other time. Never noticed dimming in previos years.
3 Responses
Dan
24 Feb 2010
greenvetter
24 Feb 2010
What you are calling the Amp gauge is a voltage gauge. If it is dipping down to 9 and then coming up to 14 you either have something loading the system or your alternator is not putting enough current/voltage at idle. Put a voltmeter across the battery terminals or put a current clamp on the battery lead to see if this is true.
Chris & Shar
24 Feb 2010
Start with the basics first. Check to see that the battery contacts are very clean, tight etc and that you have not stripped the bolt hole if you used the side posts.
you need to got to gm dealer and get updated alt connector installed, some gm trucks have this same concern 01-03
when they install connector they also add a jumper wire
everything will work like normal, no dimming