jmcdermo
New Member
On our recent trip with our 2019 2500 diesel,towing our trailer, the truck decided not to start. It was on the tail end of a 2-week trip in the Grand Canyon campground around 9am. The temp overnight had been mid 40s and it was about 55 when this happened. It went through the diesel pre-heat sequence and then gave one weak click or clunk, which was normally followed by the sound of the starter turning over, but this morning it made the half heated sound and then it would start the sequence all over again: ding, ding, ding, diesel pre-heat, etc.
Tried a jump box that the rangers had, no joy. AAA arrived and connected the jumpers from the little service truck and it turned right over. So we got on our way driving all day without shutting the truck off. The whole way I was watching the detailed voltage display. The alternator seems to be good - charging at 14.1 or 14.2v for the first part of the drive and then backing off to 13.7 or 13.6v later in the day. I took that as a sign that the batteries were back up to charge. When we got to our destination for the night I shut the engine off and checked the voltage - 12.7. Seemed like the batteries were charged.
The following morning as I started the truck the display showed 11.5v (seems bad), but the truck started and the alternator and batteries repeated the behavior of the previous day with the batteries showing 12.7v after I shut the engine off at home. This morning, it again showed 11.3v in the process of starting the truck and before the alternator kicked in.
I’m thinking failed OEM batteries. The truck is 3.6 yr old with 38.5k miles. So I took it in to an Advance Auto store, planning on getting a pair of DieHard Platinum AGM batteries. But, first I wanted the batteries to be tested. I didn’t want to buy new batteries if the existing batteries tested good. When hooking up their automated tester it threw an error about seeing “noise” in the system and prompting us to be sure everything is off. Everything I had control over *was* off.
So, before I spend $$$$$$$ at our local FCA dealer chasing electrical gremlins I borrowed a friends clamp amp meter. Here’s what I found. With the truck idling it shows almost 5A load. Immediately after shutting the truck off it drops to around 2.5A. 5 min later it’s still slightly over 2A. After 10 min it dropped to around 1.25A. And, at 15 min it dropped to 0.85A. I quit watching after 20 min with it still reading 0.85A.
For comparison I tested our 2018 BMW X3 M40i it showed a steady 1.1A after all the lights went out and the displays went back to dark after just opening the drivers door and popping the hood.
So questions:
1) feels like failed batteries not holding a charge. But I don’t want to spend for new batteries only to have the truck’s electrical system kill them too. Thoughts?
What about the “noise” in the system (load?). I’m sure we didn’t wait 15 min before trying to test the batteries at Advance. So the test equip was probably seeing the 2+A load, whatever it is.
2) After 15 min, still showing 0.85A seems pretty “normal” when compared to our BMW. That shouldn’t stop the test equip, should it?
3) What about disconnecting the Neg from the battery being tested. Since that battery won’t be grounded and the test equip clamps are only connected to the battery posts (not the vehicle ground) it shouldn’t “see” any load, right?
4) has anyone else had a similar experience?
Any thoughts or suggestions will be greatly appreciated.
Cheers!
Tried a jump box that the rangers had, no joy. AAA arrived and connected the jumpers from the little service truck and it turned right over. So we got on our way driving all day without shutting the truck off. The whole way I was watching the detailed voltage display. The alternator seems to be good - charging at 14.1 or 14.2v for the first part of the drive and then backing off to 13.7 or 13.6v later in the day. I took that as a sign that the batteries were back up to charge. When we got to our destination for the night I shut the engine off and checked the voltage - 12.7. Seemed like the batteries were charged.
The following morning as I started the truck the display showed 11.5v (seems bad), but the truck started and the alternator and batteries repeated the behavior of the previous day with the batteries showing 12.7v after I shut the engine off at home. This morning, it again showed 11.3v in the process of starting the truck and before the alternator kicked in.
I’m thinking failed OEM batteries. The truck is 3.6 yr old with 38.5k miles. So I took it in to an Advance Auto store, planning on getting a pair of DieHard Platinum AGM batteries. But, first I wanted the batteries to be tested. I didn’t want to buy new batteries if the existing batteries tested good. When hooking up their automated tester it threw an error about seeing “noise” in the system and prompting us to be sure everything is off. Everything I had control over *was* off.
So, before I spend $$$$$$$ at our local FCA dealer chasing electrical gremlins I borrowed a friends clamp amp meter. Here’s what I found. With the truck idling it shows almost 5A load. Immediately after shutting the truck off it drops to around 2.5A. 5 min later it’s still slightly over 2A. After 10 min it dropped to around 1.25A. And, at 15 min it dropped to 0.85A. I quit watching after 20 min with it still reading 0.85A.
For comparison I tested our 2018 BMW X3 M40i it showed a steady 1.1A after all the lights went out and the displays went back to dark after just opening the drivers door and popping the hood.
So questions:
1) feels like failed batteries not holding a charge. But I don’t want to spend for new batteries only to have the truck’s electrical system kill them too. Thoughts?
What about the “noise” in the system (load?). I’m sure we didn’t wait 15 min before trying to test the batteries at Advance. So the test equip was probably seeing the 2+A load, whatever it is.
2) After 15 min, still showing 0.85A seems pretty “normal” when compared to our BMW. That shouldn’t stop the test equip, should it?
3) What about disconnecting the Neg from the battery being tested. Since that battery won’t be grounded and the test equip clamps are only connected to the battery posts (not the vehicle ground) it shouldn’t “see” any load, right?
4) has anyone else had a similar experience?
Any thoughts or suggestions will be greatly appreciated.
Cheers!
