2003 Ram 2500 headlights come on when truck is off and battery(s) will drain.

[Bruce F]

I'm not sure I'd trust a boneyard BCM. The BCM in the vehicle may not be the correct one or a good one.

Totally possible!

The symptoms you list are associated with a defective BCM A. scan tool can determine which modules remain on after the rest go into sleep mode, and of course troubleshooting the excessive current draw (should be 50-70 MA.).

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 146503 miles.

Dusty,

Thanks form chiming in with the tips and info.
I am not yet skilled/educated enough to determine how to do this.
My scanner, is a little older SnapOn Solus ultra.
It was purchased new (2006?) several years after this 2003 truck was built, so it may be able to watch the modules?? IDK
Would the modules all go to "sleep" while the scanner is plugged in?? And I was checking stuff??

I do not have TONS of experience with the Dodge trucks, as most of my customers have GMs, Fords, or Med/HD trucks.

This customer has taken the truck and will continue to use it daily (with the 1/2(?) amp draw), until it becomes a problem.
I hadn't had it on a battery charger for three(?) days. It started each day, so the drain hasn't been enough to kill the batteries. I did caution them, if the truck were to sit for a longer period (perhaps a couple weeks without use) they should disconnect the negative terminals from both batteries.

They are ok with this scenario. They did replace the BCM with one from a junkyard, but it still had the same "headlights come on when truck is shut down" symptom.

I'm sure I'll see the truck again. I've worked on a few of their trucks. They've recently (last weekend) purchased a 2016 RAM 2500 4x4 234k miles 6.7(?) from Texas, and have been asking me about some steering "issues". It sounds like from the symptoms it may have a tight u joint in the front axle.
We will see..

I will get back and update this thread with new info when I get any.

I still welcome any feedback from others that have had similar experience or knowledge about tis symptom/repair...
I'm always willing to learn, even after a lifetime of doing this work. Every day is something more to learn.

Thanks,
Bruce F

 

[Dusty]

Totally possible!

Dusty,

Thanks form chiming in with the tips and info.
I am not yet skilled/educated enough to determine how to do this.
My scanner, is a little older SnapOn Solus ultra.
It was purchased new (2006?) several years after this 2003 truck was built, so it may be able to watch the modules?? IDK
Would the modules all go to "sleep" while the scanner is plugged in?? And I was checking stuff??

I do not have TONS of experience with the Dodge trucks, as most of my customers have GMs, Fords, or Med/HD trucks.

This customer has taken the truck and will continue to use it daily (with the 1/2(?) amp draw), until it becomes a problem.
I hadn't had it on a battery charger for three(?) days. It started each day, so the drain hasn't been enough to kill the batteries. I did caution them, if the truck were to sit for a longer period (perhaps a couple weeks without use) they should disconnect the negative terminals from both batteries.

They are ok with this scenario. They did replace the BCM with one from a junkyard, but it still had the same "headlights come on when truck is shut down" symptom.

I'm sure I'll see the truck again. I've worked on a few of their trucks. They've recently (last weekend) purchased a 2016 RAM 2500 4x4 234k miles 6.7(?) from Texas, and have been asking me about some steering "issues". It sounds like from the symptoms it may have a tight u joint in the front axle.
We will see..

I will get back and update this thread with new info when I get any.

I still welcome any feedback from others that have had similar experience or knowledge about tis symptom/repair...
I'm always willing to learn, even after a lifetime of doing this work. Every day is something more to learn.

Thanks,
Bruce F

Hi Bruce,

Your Solus is probably fine, especially if it has the latest subscription. The techs I know all seem to have one, and they seem to also have a number or competitive models. Some scan tools are favored for different reasons.

I'm not sure where you are in your diagnostic procedure. I would start by logging all stored codes and erase them. Run the engine and recheck for any reoccurring codes.

Enter the module scan and see if any are not communicating. You should also note when they enter the sleep mode.

The year can make this vary, but they should all be asleep with 4-10 minutes. If one stays operative, this is likely the source of the issue. Refer to the wiring diagram and pull the fuse for this circuit to confirm.

At this point you'll need to take voltage measurements to see why that particular module is staying alive. If there's no voltage to keep the module alive, then the problem is likely to be the module.

If there's voltage there when it shouldn't be then you'll need to troubleshoot back to the PCM. Now this is where you'll be introduced to what Dodge called the Total Integrated Power Module (TIPM). This is similar in purpose to how GM piggybacks wiring underneath the fuse block, except you'll find more relays (depending on the year).

Because of the year and your geographic location the TIPM has been susceptible to corrosion issues.

Hopefully this has been helpful.

Best of luck,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 146524 miles.

 

[Bruce F]

Your Solus is probably fine, especially if it has the latest subscription. The techs I know all seem to have one, and they seem to also have a number or competitive models. Some scan tools are favored for different reasons.

My scan tool does NOT have the latest subscription. Actually, it is only updated to 2012.
I'd think since this truck is a 2003 it would be sufficient, but IDK...

I do have a friend that has newer scan tools as well as some other scan tools we might try in the future.

I'm not sure where you are in your diagnostic procedure. I would start by logging all stored codes and erase them. Run the engine and recheck for any reoccurring codes.

I'm actually done with the truck at this time. Customer has taken it as of Monday.

If or when the truck comes back, I will refer back to this thread for the suggested tips.
This customer tends to do their own work, they bring stuff to me when it's beyond their capability (apparently this is beyond mine too!).

It takes time before customers realize, having an actual mechanic do the work most times is better than struggling themselves.

Some day, I might be able to just hand a shop the keys and say fix it!! (but I doubt it).

 

[Dusty]

My scan tool does NOT have the latest subscription. Actually, it is only updated to 2012.
I'd think since this truck is a 2003 it would be sufficient, but IDK...

I do have a friend that has newer scan tools as well as some other scan tools we might try in the future.

I'm actually done with the truck at this time. Customer has taken it as of Monday.

If or when the truck comes back, I will refer back to this thread for the suggested tips.
This customer tends to do their own work, they bring stuff to me when it's beyond their capability (apparently this is beyond mine too!).

It takes time before customers realize, having an actual mechanic do the work most times is better than struggling themselves.

Some day, I might be able to just hand a shop the keys and say fix it!! (but I doubt it).

Your scan tool is probably good for 2003.

With a 500 milliamp drain I think there's still a problem, but if it works for the customer then maybe a DIY'er customer will be satisfied.

Anyways, best of luck and hopefully your customer will be happy.

Best regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 146668 miles.