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2017 Ram 1500 Rebel Battery Draining Overnight - Parasitic Draw?

0

Eric V. · rep 0 · May 22, 3:34 AM · 1 replies · solved · Question

Vehicle: 2017 Ram 1500 Rebel

Hi all,

My 2017 Ram 1500 Rebel has developed a really annoying problem: the battery keeps dying overnight. If I don't drive it for 12-24 hours, it's completely dead. I've already replaced the battery, thinking that was the issue, but the new one is doing the exact same thing. The alternator was also tested and is charging fine.

It feels like something is staying on and draining power even when the truck is off. I've checked all the obvious things like interior lights, but nothing seems to be left on. Could this be a parasitic draw from a module or something similar?

Has anyone with a 2017 Ram experienced this kind of rapid battery drain? What should I be looking for, or is this a job for the pros?

✓ Accepted solution

ClearTheCode Admin

ClearTheCode Team · rep 0 · May 22, 3:34 AM

0

ClearTheCode admin answer:

A parasitic draw can be incredibly frustrating, especially when it leaves you with a dead battery. Here's how to approach diagnosing it:

  1. Confirm the Draw: Ensure all doors are closed, the hood is latched, and the truck has been 'asleep' for at least 30-60 minutes (modules can take time to power down). Using a multimeter, connect it in series between the negative battery post and the negative battery cable. A healthy draw should typically be under 50mA (0.05 Amps).
  2. Fuse Pull Method: If the draw is high, start pulling fuses one by one from the fuse boxes (under the hood and inside the cabin) while monitoring the multimeter. When the amperage drops significantly, you've identified the circuit causing the draw. This narrows down the culprit.
  3. Common Culprits: In Ram trucks, common sources of parasitic draws include:
    • Radio/Uconnect Module: Sometimes they don't power down correctly.
    • Telematics Module (e.g., SiriusXM, Uconnect Access): Can stay active.
    • Body Control Module (BCM): A faulty BCM can prevent other modules from sleeping.
    • Aftermarket Accessories: Anything wired directly to the battery that isn't properly switched.
    • Alternator Diode Failure: Though less common if the alternator tested good, a failing diode can cause a slight draw.
  4. OBD-II Scan: While there isn't a specific OBD code for parasitic draw, a scan might reveal 'U' codes (network communication errors) if a module is failing to shut down or is constantly trying to communicate, which could contribute to the draw.

When to See a Shop: If you're uncomfortable with electrical testing or can't pinpoint the circuit using the fuse pull method, a professional diagnostic is recommended. Automotive electricians have specialized equipment and experience to trace parasitic draws, which can be complex and time-consuming. They can also test individual modules for internal faults.

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