System: Powertrain (P-Code)
SAE Standard (Generic)
Family: Coolant Degassing Valve
Code P2679: Coolant Degassing Valve Control Circuit Low
Diagnostic & Technical Explanation
Code P2679 (Coolant Degassing Valve Control Circuit Low) sets when the ECM detects an open circuit, a short to ground, or a short to voltage while driving the solenoid valve that routes coolant through the degas bottle to separate entrained air from the cooling circuit. Causes are a failed valve solenoid coil, coolant deposits jamming the small valve orifice, or damaged control wiring near the coolant reservoir.
First-listed procedure
Rank #1
Flush deposits from degassing valve
Moderate DIY
This is the first procedure in the authored
consideration order, not a measured cause likelihood. Execute it only when its prerequisites
and diagnostic findings support it. Its cost and labor estimates (where known), the step-by-step procedure and the
remaining 2 procedure(s) are in the licensed dataset. Ordering context.
Full family: Coolant Degassing Valve
What this page does not show
This page publishes the fault mechanism and the code index. The licensed dataset adds, for
every one of the 15,886 codes, the full authored repair set (56,729 procedures in total)
with the fields deliberately withheld here:
- Procedures 2..n after the first-listed procedure
- Aftermarket parts cost ranges in USD (
est_parts_cost_min/max_usd)
- Professional labor-hour estimates (
est_labor_hours)
- Step-by-step diagnostic and repair instructions
- Replacement-part mappings and catalog lookups
- 6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)