Hi all

99 Ram CTD

Our old Ram is no longer our primary vehicle and doesn't get run often. This last winter only ran it three or four times. Live in Southern Alberta. Truck is parked outside. Startup and operating temps are right around the freezing mark. The last couple of times it was run it barely started. The Batteries were six years old so I thought that they were probably getting tired so I replaced them. Just fired it up and took it for a 20 minute run on the highway and took some readings after I got back.

System voltage at idle and at operating temperature (tach says about 800 RPM) is 14 volts

Voltage at about 1000 RPM and higher is about 14.2 volts

Took voltage with a digital multimeter.

Took voltage with the truck shut off got 12.97 volts

I'm wondering if taking short trips around town in the winter with the grid heaters cycling and such might not sufficiently charge the batteries.

Your thoughts?

Thanks
John

 

I don't know about your '99 but the owners manual for my '95s say to start and run the engine at least 1200 rpm for 20 minutes every 21 days to keep the batteries charged.

 

14 volts is a good charging voltage so I would say your generator/alternator is fine.

You just need to take it around town more often to keep things happy.

 

I also don't use mine much in the winter, but in a climate milder than yours. I noticed it taking a little more cranking to start if I didn't keep a portable trickle charger on it in the garage, most of the time. Once it wouldn't crank at all until I threw on the big charger, and then I kept the trickle on it always. That was a hassle so I recently installed a tiny 1.25 amp maintence charger in the engine compartment, with the pigtail poking out alongside the engine heater. I keep it plugged in, but switch the extension cord to the block heater several hours before I intend to drive it. My AGM batteries lasted 8 years.

 

Installing a maintenance charger sounds like a good idea. I think I might do that.