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Discussion Starter #1
Hey folks, anyone here have any insight and suggestions on the following? '

2016 Rebel 5.7 with air ride suspension:

Went on a long haul with the Mrs. from NJ to NH last weekend. Truck ran and drove, started flawlessly. Parked it after our 5 hour drive home and the next day I have the Battery Saver Mode warning, radio went out, and I have the backup light out warning.

I bought the truck used with 59k miles in January of this yr. Previous owner had installed LEDs throughout the truck. No issues with lights since purchasing the vehicle 8 months ago and about 3k miles of driving. I threw the battery on the trickle charger and it was restored within an hour. Pulled all fuses and relays and didnt see anything out of sorts. No burning ends and no broken filaments. I pulled the third brake light bulb and all looked good (some burned plastic on the receiver but bulb was fresh looking). I pulled the LEDs from the tail lights and again, all looked good. In fact all lights throughout the truck functioning as they should.

I tested the alternator with the trickle charger "alternator test" setting and all checked out good. I decided to just throw a new battery in it just in case the old one was reading a false full charge. No change. New battery also threw the dash messages "Battery Saver Mode" and "Backup Light out". Returned the new battery.

I then hooked a test light to the negative terminal and the negative battery wire harness. Light was dimly lit and did not seem to have a parasitic draw. I pulled all fuses and relays while light was lit on tester and nothing changed. Again all seemed good.

I'm not afraid to turn a wrench and trying to avoid a visit to the stealership.
Any suggestions on what to check next?

Thanks in advance,
JM
 

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Battery saver mode light normally is a bad Intellegent Battery Sensor IBS. It’s on the neg. battery terminal. Even if all your LEDs seem to be working properly they can still cause issues. I know a lot of people install them and are quite popular and normally work fine. But.... we see add on LEDs causing so many different electrical issues even when installed properly, and trust me people don’t want to hear that the LEDs they installed are causing the problem. Personally I’d ditch the aftermarket LEDs and go back to original. That or maybe try one of the newer higher quality LED kits that are out now.
 

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Discussion Starter #3
Thanks for the reply Mopaird. I bought the truck with the LEDs throughout not thinking anything of it at the time. Not something I typically spend money on. Nor would I have gone that route if it were up to me. Got the truck for a song and I've been happy with it for months. Frankly still happy with it even though the battery saver gremlins have has me stumped.

The warning light has been off now for the last 2 days/ 4 drive cycles, but I'm not confident she's done screwing with me. I'll look into the IBS as you've recommended. If she comes back hopefully that does the trick. I appreciate the advice!

Cheers!
 

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LED lights all have "drivers" and this is the point of failure. Cheaper lights come with cheaper drivers and are more likely to fail. In theory if the LED lights are off there should not be a current draw but if a switch is defective it can allow current to flow anyway. I have had rocker switches for cabin lights on vehicles that seemed to be off but were allowing current to pass through and would drain the battery overnight.

A temporary fix is one of the battery lever switches that can be attached to the battery post and at least save you from a deeply discharged battery which will shorten the life of the battery.

I would not go to the dealer as nearly all of the mechanics I have found at dealers have no troubleshooting abilities. An auto electrical shop would be my choice. At least with all the troubleshooting work you have done already they can skip over what you have checked and possibly find the source of the problem sooner.

You said you checked the relays but did you check the voltage regulator relay that is between the alternator and the battery? The PCM has internal diodes that can fail. I would also not trust the alternator diagnosis from the trickle charger. The all in one type of tools are usually not very good and any single feature and I have seen where they fail completely to detect problems caught by dedicated testers.
 

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Discussion Starter #5
Thank you for the response, Calson. I checked all relays within the engine bay fuse panel only. I didn't get beyond that. Also in agreement that the trickle chargers are typically good for float charging only. I also tested with the voltmeter and again all seemed good.

I turned my lights off auto and it hasn't come back again. Could be coincidence but guys on the RAM diesel forum seemed to do this with success and the warning went away.

If and when the warning light comes back I will do a more thorough chase. It could very well be coming from the drivers in the LEDs as you suggest. Mopair suggested I check the IBS cable/ unit. I pulled all the light bulbs, also pulled the headlights and inspected the bulbs and the ballasts. If it's a bad driver I won't see that during a visual. So to your point I need someone good with chasing current. I'll have to look around for an auto electronics shop near me.

In agreement on techs from the dealerships. They are overpaid parts changers in the majority of instances. They typically guess and swap parts. Not truly identifying root cause unless it's glaringly obvious. I own 6 vehicles and rarely ever bring anything to the dealer unless there is a standing warranty and I cant locate the issue myself. Guys that suggest going to a dealership for fixes crack me up. Especially if that's their advice on a forum. Save the keys strokes next time and forego the worthless advice.

Thanks again for the insight. I'll let you all know how this turns out if the the warning comes back.

Cheers!
 
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