Cold weather - Startup - Large battery drain every 5 seconds (relay)

[Thorvald]

After replacing both my batteries, and turning on the voltmeters on my CTS3 edge, dashboard and setting alarms, I have noticed during the cold weather on initial start up while idling there is a relay that is activating every five seconds sounds like it’s near the center of the dash towards the firewall, so could be in the engine bay. It’s cycles on with a fairly loud click more like a contactor and brings the voltage from 13.56 down to 11.81 for about 5 seconds then the relay deactivates and back up to 13.56v. It seems to go away once the engine is either up to temperature or I start driving, but I need to monitor it more. Surprised I have the full snow plow package that the large alternators can’t keep up.

That’s quite the draw so just curious what it is. I had assumed the grid heater only turned on before engine start up, but maybe the grid heater cycles often on until the engine reaches a certain temperature?

Anyone got one of those awesome start up checklist from the service manual or the diagnostic software? That indicates what all occurs on start up?

 

[flan]

What you’re seeing is the grid heater cycling. Perfectly normal.

 

[Great White North Eh]

They keep cycling after start up to …’’help with emissions and save the planet’’or something like that.

 

[Deleted member 47449]

I never wanted our 2024 Ram diesel versus our 2016 Ram 6.4L due to just having to go outside and plug it in. Buried 225 feet of electric cable to the pole barn last summer to make it much easier to cold start a diesel. Maybe by doing so I will help contribute to the warming of the planet.

 

[whitexc]

That’s cold


Sent from me

 

[H3LZSN1P3R]

That’s cold


Sent from me

Thats a mild day for the north lol

 

[dngrabs]

They keep cycling after start up to …’’help with emissions and save the planet’’or something like that.

We had a 1992 Dodge with the 5.9 Cummins that would cycle the heater after start up, so it doesn't seem to be because of the emissions crap.

 

[AH64ID]

I never wanted our 2024 Ram diesel versus our 2016 Ram 6.4L due to just having to go outside and plug it in. Buried 225 feet of electric cable to the pole barn last summer to make it much easier to cold start a diesel. Maybe by doing so I will help contribute to the warming of the planet.

View attachment 81208

That’s the nice thing about these motors, they just start.

I started my 5.9 with weak batteries and the grid heater removed without using the block heater in -25°F. It might not have been happy, but it started better that a powerstroke without glowplus on a +40°f day.

Hope that was some big cable at 225’.