Starting/Charging System - 94 GMC C1500

[Friday]

Make

GMC

Model

C1500

Year

1994

Miles

195K

Engine

5.7L

I seldom drive my pickup, just trips to the box stores on the other side of town (10-15 miles). So I keep a solar battery minder on the truck to keep the battery up. Recently, on these short trips, it spins up fine when I leave the house, but will barely crank when I leave the store. I took some readings: Sitting dead with the solar minder unattached, I get 12.5V at the battery. With the truck running, I get 14.5V at the battery. With a load on the system (headlights, fan, and signals), I get 14.2V at the alternator and 13.8V at the battery. Where would I start to look for the problem?

 

[billr]

Look for a date code on the battery. If it is between 5 and 10 years old, I would be inclined to throw a new battery at it. They tend to lose amp-hour capacity with age. Maybe driving it for those 10-15 miles isn't enough charging time to "top it off" as completely as the long-term charge from the solar charger.

Or, take it your local FLAPS for a load test.

 

[paulo57509]

After you get it sorted, get a battery maintainer (shop around for the best price):

https://www.batterymart.com/p-batteryminder-1510-12-volt-1_5-amp-charger.html

This maintainer will work plugged into an extension cord as well. It comes with a 2-wire trailer type pigtail so it's convenient to plug/unplug to the battery. If there's room, you can use these to replace the side terminal cable bolts which make the vehicle half of the pigtail connection to the battery that much easier.

https://www.amazon.com/Terminal-Compatible-Accessories-Standard-Extension/dp/B086RMH6CB/ref=sr_1_5?dchild=1&keywords=side+post+battery+terminals&qid=1634685473&sr=8-5

This old Die Hard that lasted 16 years with one of these in use.

 

[Friday]

After you get it sorted, get a battery maintainer (shop around for the best price):

https://www.batterymart.com/p-batteryminder-1510-12-volt-1_5-amp-charger.html

This maintainer will work plugged into an extension cord as well. It comes with a 2-wire trailer type pigtail so it's convenient to plug/unplug to the battery. If there's room, you can use these to replace the side terminal cable bolts which make the vehicle half of the pigtail connection to the battery that much easier.

https://www.amazon.com/Terminal-Compatible-Accessories-Standard-Extension/dp/B086RMH6CB/ref=sr_1_5?dchild=1&keywords=side+post+battery+terminals&qid=1634685473&sr=8-5

This old Die Hard that lasted 16 years with one of these in use.

View attachment 11427

Read the original posting: "I seldom drive my pickup, just trips to the box stores on the other side of town (10-15 miles). So I keep a solar battery minder on the truck to keep the battery up. "

 

[grcauto]

My money is on you needing a new battery.

 

[paulo57509]

Read the original posting: "I seldom drive my pickup, just trips to the box stores on the other side of town (10-15 miles). So I keep a solar battery minder on the truck to keep the battery up. "

Sorry. I thought you were referring to those cheap solar panels with alligator clips.