Glow Plug Control Circuit
The MAXXFORCE-P0670-DT (MaxxForce) diesel fault code means: Glow Plug Control Circuit. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $150-$600
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Common Symptoms
- Hard cold start
- CEL
Probable Causes (Ranked by Likelihood)
- Failed glow plug control module Likely
- Open or shorted glow plug Possible
Step-by-Step Diagnostic Procedure
Check glow plug resistance (should be 0.5-1.5 ohms).
Replace GPCM if driver fault confirmed.
Frequently Asked Questions
What is P0670 on a MaxxForce DT (7.6L)?
P0670 on a MaxxForce DT (7.6L) (2007-2015) indicates: Glow Plug Control Circuit. This is a known fault code on the MaxxForce engine family and typically points to the causes listed above.
Can I drive with P0670 on my MaxxForce?
Yes, you can generally drive with this code, but diagnose soon to prevent secondary damage.
How much does it cost to fix MaxxForce P0670?
Repair cost is typically $150-$600 depending on the underlying cause and shop rate. Many MaxxForce faults (especially EGR cooler, head bolt, and VGT repairs) are major expenses that drove fleet owners to repower with Cummins or retire these trucks early.