P0670 on Chevrolet
Glow Plug Module Control Circuit
P0670 on Chevrolet vehicles indicates glow plug module control circuit. Au7o has documented this code across 1 Chevrolet model — most commonly on Express. This code indicates the engine computer detected a fault in the control circuit between the PCM and the glow plug control module on a diesel engine. The glow plug module energizes the glow plugs to preheat the cylinders for cold starting. A fault here mainly causes hard cold starts, rough cold-start running, and white smoke until the engine warms up. Typical repair costs on Chevrolet range from $300 to $1,800, depending on the specific model and root cause.
Common Causes of P0670
- •Faulty glow plug control module
- •Open or shorted wiring between PCM and glow plug module
- •Corroded or loose module connectors
- •Blown fuse feeding the glow plug system
- •Poor ground at the module
- •PCM control circuit fault
P0670 on Chevrolet by Model
Chevrolet Express(1 issue)
- 6.6L Duramax LGH Glow Plug and Glow Plug Control Module Failure2011-2016
The 6.6L Duramax LGH offered in Express 2500/3500/4500 vans from 2011 to 2016 has a well-documented glow plug system weakness. Individual glow plugs fail open, and the glow plug control module itself develops open-driver and no-power-to-glow-plug faults - a failure mode common enough that specialist board-repair houses list the 2011-2016 Chevrolet Express 6.6L LGH GPCM as a standing repair line. GM issued a service bulletin covering 2011-2012 Express vans with the LGH and LML Duramax where the malfunction indicator lamp illuminates for glow plug faults; the bulletin notes there is usually no drivability complaint in mild weather, but harder cold starting may be present. In practice owners in cold climates get extended cranking, white startup smoke and a rough first minute of running, plus a persistent MIL that will fail an inspection. Do not confuse this with the 2023+ Express, which uses the completely different 6.6L L5P Duramax and whose injector-related complaints are their own story.
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View P0670 across all makes →Frequently Asked Questions
What does P0670 mean on Chevrolet?▼
P0670 stands for "Glow Plug Module Control Circuit." This code indicates the engine computer detected a fault in the control circuit between the PCM and the glow plug control module on a diesel engine. The glow plug module energizes the glow plugs to preheat the cylinders for cold starting. A fault here mainly causes hard cold starts, rough cold-start running, and white smoke until the engine warms up. On Chevrolet specifically, this code is documented across 1 model.
What causes P0670 on Chevrolet vehicles?▼
Common causes on Chevrolet: Faulty glow plug control module, Open or shorted wiring between PCM and glow plug module, Corroded or loose module connectors, Blown fuse feeding the glow plug system, Poor ground at the module. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0670 on a Chevrolet?▼
Repair costs on Chevrolet range from $300 to $1,800, depending on the specific model and root cause.
Which Chevrolet models have P0670 documented?▼
Au7o has documented P0670 on 1 Chevrolet model: Express.