Fault Family System: Powertrain (P-Codes) 15 SAE Codes

EGR Cooler Bypass Valve Circuit

Diagnostic & Technical Explanation

Code P2425 (EGR Cooling Valve Control Circuit/Open) covers the motorized bypass valve that routes EGR gas around the cooler during cold starts to speed warm-up, then through it once operating temperature is reached, flagging an open/shorted control circuit, an out-of-range voltage, or a mechanically stuck-open/stuck-closed report on single or dual-bank coolers. Carbon and soot buildup jamming the valve shaft is the leading mechanical cause, while a failed valve motor or damaged control wiring accounts for most electrical faults.

These 15 diagnostic trouble codes share one detection mechanism and one repair path, which is why MechanicDB groups them into a single authored fault family rather than repeating the same explanation 15 times.

Codes in this family (15)

Code	Definition	Repair coverage
P2425	EGR Cooling Valve Control Circuit/Open	4 ranked fixes
P2426	EGR Cooling Valve Control Circuit Low	4 ranked fixes
P2427	EGR Cooling Valve Control Circuit High	4 ranked fixes
P245A	EGR Cooler Bypass Control Circuit/Open Bank 1	4 ranked fixes
P245B	EGR Cooler Bypass Control Circuit Range/Performance Bank 1	4 ranked fixes
P245C	EGR Cooler Bypass Control Circuit Low Bank 1	4 ranked fixes
P245D	EGR Cooler Bypass Control Circuit High Bank 1	4 ranked fixes
P248E	EGR Cooler Bypass Control Circuit/Open Bank 2	4 ranked fixes
P248F	EGR Cooler Bypass Control Circuit Range/Performance Bank 2	4 ranked fixes
P2490	EGR Cooler Bypass Control Circuit Low Bank 2	4 ranked fixes
P2491	EGR Cooler Bypass Control Circuit High Bank 2	4 ranked fixes
P24A5	EGR Cooler Bypass Control Stuck/Open Bank 1	4 ranked fixes
P24A6	EGR Cooler Bypass Control Stuck/Open Bank 2	4 ranked fixes
P26FB	EGR Cooler Bypass Control Stuck Closed Bank 1	4 ranked fixes
P26FC	EGR Cooler Bypass Control Stuck Closed Bank 2	4 ranked fixes

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)

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