P2500high severityPowertrain

Generator Lamp/L Terminal Circuit Low

on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD

What this code means

Low signal on the alternator lamp/exciter circuit, preventing proper charging regulation.

Symptoms

  • Battery light on
  • Low charging voltage
  • Check engine light

Common causes

  • Broken exciter wire
  • Failed voltage regulator
  • Corroded alternator connector
  • Blown dash bulb

Diagnostic steps

  1. Check charging system voltage
  2. Inspect alternator connector
  3. Measure exciter circuit voltage

Repair notes

Repair exciter circuit wiring or replace alternator.

Other Powertrain codes on this vehicle

🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Mechanic · 20+ years. Spot an error? Use the Help link above — a human reads every report.
Stuck on this repair? Take it to The Diag Desk — ask a master tech about this exact car → real human answer within 24h, never AI
🔓 LIBERATED FOREVER
The 2014 Ram 2500 6.7L I6 Cummins Diesel repair data is free for every DIYer and shop on earth, permanently, because Lost Pines Precision Automotive, Bastrop, TX paid $99 to unlock it.
Mitchell1 charges $169/mo for this. ALLDATAdiy charges $30/yr per vehicle. Open Labor Project is free permanently, because of community sponsors like Lost.
Free another vehicle →
Building an app?
Free API access to all this data — 10 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →