New Batteries No Start

[kamccarthyinc]

Need help here guys (and girls)! My '03 GMC 2500 HD has been sidelined since the first week of September, (day after Hurricane Irene went through). I parked the truck the day before with no issues, lifted the ez dumper about a foot so any water would drain. Went out two days later, turned the key click, click, click. My truck has the 8.1 L gas engine which has two batteries. Took both batteries out, took them down to my local parts place and had them tested under load. One was completely gone (no reading) the other was holding at like 10-11 volts. Replaced the dead one and charged the one that was holding. Day later truck starts, dump bed works fine. Park the truck, next day no start. Go back to auto parts place and replace the second battery, truck starts, drive it for an hour, no problems, battery gauge on dash is right between the 9 and 14 volts. While running I check the alternator with a multimeter 14.55 volts at idle. Shut the truck down. go back out today, click click click, no start. Charge both NEW batteries and hook them up without the + and - cables that power the bed. Nothing, no click no dome light or door chime. Check volts of battery one is 12.65 the other is 13.40 volts. Going to let it sit over night to see if there is a drain on the system. Any ideas? Anything is greatly appreciated. Thanks, Keith

[Diesail]

I would start by checking all the battery cables, sounds like a loose or corroded ground connection.

[kamccarthyinc]

I would start by checking all the battery cables, sounds like a loose or corroded ground connection.

 

 

Thanks Diesail. Do you know if both ground cables terminate at the same place?

[Diesail]

I would start by checking all the battery cables, sounds like a loose or corroded ground connection.

 

 

Thanks Diesail. Do you know if both ground cables terminate at the same place?

 

 

I do not, but I thought on the gasser with second battery that only one of the two did starting chores. The second one powered the trailer plug and a relay combined them when the truck was running.