Starter Relay Circuit
The DURAMAX-P0615 (Duramax) diesel fault code means: Starter Relay Circuit. This is a moderate severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
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What Are the Symptoms of DURAMAX-P0615?
- Check Engine Light on
- Engine may not crank
- Intermittent starting
What Causes DURAMAX-P0615? (Most Likely First)
- Failed starter relay High
- Open or shorted relay control wiring Moderate
- Loose or corroded relay socket Moderate
- Engine computer driver fault Low
Can I Still Drive with DURAMAX-P0615?
Yes, with caution. DURAMAX-P0615 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0615 mean on a Duramax?
P0615 means Starter Relay Circuit. The engine computer has detected a fault in the starter relay control circuit.
Is P0615 a Duramax-specific code?
No. P0615 is a generic OBD-II code defined by SAE J2012, so it means the same thing on any vehicle that sets it. The exact conditions GM uses to set it on its diesels are in GM service information.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose DURAMAX-P0615?
Check the starter relay and its socket.
Check the relay control circuit for an open or a short.
Check that the engine computer commands the relay when cranking.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0615 as a generic OBD-II code)
P0615 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
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