1999 battery drain

[nascar mark]

Hi Guys. I have a ton of mechanical experience but very weak in electrical. I hate it. Bought a 1999 Cummins for my daughter that will be turning 16 in Sept ( she will be paying me back for the truck, lol ) and even with new batteries, if it sits for a week or more, the batteries drain to the point it will not start.

I have tried to research this problem & have eliminated the seat belt modules are not the problem. What else could it be ?

Any help would be much appreciated.


On a side not, it also does what I think is a weird thing. Sometimes when you turn the key to the on position, the wait to start light doesn't come on & no matter how long you crank, it will not fire. I know the ambient/engine temp sensor monitors this but if you turn key off & then back to on, the wait to start light usually comes on & once it goes off, it fires up right away. again even with engine warm, if the wait to start light doesn't come on even for 1 sec, you can crank to the cows come home & it will never fire up. Just thought I would throw that in here, incase it has something to do with battery drain ?

Other than that, everything else works as should.

Thanks

 

[tomblue01]

"...incase it has something to do with battery drain ?" I don't think it does. Youtube 'parasitic draw test'. EricTheCarGuy, HumbleMechanic, BleepinJeep all have good vids on the topic.

Your 'wait to start' light issue is definitely odd. In the summer months, I don't wait for my WTS light, and she fires right up. A crank with no fire... FSS possibly not active when you don't see the WTS light? ...could there be some intermittent contact inside your ignition switch causing this issue?

 

[Bromiley99]

The battery drain could be lots of things hard to say.
As for your other problem, I’ve seen lots of threads pointing towards ECM causing the no start issue here is one for example.
https://mopar1973man.com/topic/10686-no-wait-to-start-light/
Good luck!

 

[DavidC]

You could start by removing the IOD fuse at the Drivers side dash when it's going to be parked for a while and see what happens. That fuse powers some things like radio memory etc. when not running.

 

[nascar mark]

Thanks guys.