Transmission Control System (MIL Request)
The DURAMAX-P0700 (Duramax) diesel fault code means: Transmission Control System (MIL Request). This is a serious severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
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What Are the Symptoms of DURAMAX-P0700?
- Check Engine Light on
- Possible shifting problems, depending on the transmission fault
What Causes DURAMAX-P0700? (Most Likely First)
- A separate transmission fault code stored in the transmission control module High
Can I Still Drive with DURAMAX-P0700?
Yes, with caution. DURAMAX-P0700 is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0700 mean on a Duramax?
P0700 means Transmission Control System (MIL Request). The transmission control module has stored its own fault code and asked the engine computer to turn on the Check Engine Light.
Is P0700 a Duramax-specific code?
No. P0700 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-P0700?
Read codes from the transmission control module itself; P0700 only says that it has one.
Diagnose the transmission code it reports.
Clear codes and confirm P0700 does not return once the transmission fault is fixed.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0700 as a generic OBD-II code)
P0700 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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