Fault Family System: Powertrain (P-Codes) 21 SAE Codes

Reductant Injection Valve Circuit

Diagnostic & Technical Explanation

P201A (Reductant Injection Valve Circuit Range/Performance Bank 2 Unit 1) is set by the SCR dosing module when a specific reductant injector unit fails to draw its expected coil current on command, whether from an open winding, a shorted driver, or a valve mechanically stuck. Because the dosing valve lives directly in the hot, urea-crystal-prone exhaust stream, the most frequent physical cause is crystallized urea seizing the pintle, followed by a corroded connector at the dosing module and, less often, a burned-out injector coil.

These 21 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 21 times.

Codes in this family (21)

Code	Definition	Repair coverage
P201A	Reductant Injection Valve Circuit Range/Performance Bank 2 Unit 1	4 ranked fixes
P202E	Reductant Injection Valve Circuit Range/Performance Bank 1 Unit 1	4 ranked fixes
P2047	Reductant Injection Valve Circuit/Open Bank 1 Unit 1	4 ranked fixes
P2048	Reductant Injection Valve Circuit Low Bank 1 Unit 1	4 ranked fixes
P2049	Reductant Injection Valve Circuit High Bank 1 Unit 1	4 ranked fixes
P2050	Reductant Injection Valve Circuit/Open Bank 2 Unit 1	4 ranked fixes
P2051	Reductant Injection Valve Circuit Low Bank 2 Unit 1	4 ranked fixes
P2052	Reductant Injection Valve Circuit High Bank 2 Unit 1	4 ranked fixes
P2053	Reductant Injection Valve Circuit/Open Bank 1 Unit 2	4 ranked fixes
P2054	Reductant Injection Valve Circuit Low Bank 1 Unit 2	4 ranked fixes
P2055	Reductant Injection Valve Circuit High Bank 1 Unit 2	4 ranked fixes
P2056	Reductant Injection Valve Circuit/Open Bank 2 Unit 2	4 ranked fixes
P2057	Reductant Injection Valve Circuit Low Bank 2 Unit 2	4 ranked fixes
P2058	Reductant Injection Valve Circuit High Bank 2 Unit 2	4 ranked fixes
P208E	Reductant Injection Valve Stuck Closed Bank 1 Unit 1	4 ranked fixes
P208F	Reductant Injection Valve Stuck Closed Bank 2 Unit 1	4 ranked fixes
P20F6	Reductant Injection Valve Stuck Open Bank 1 Unit 1	4 ranked fixes
P20F7	Reductant Injection Valve Stuck Open Bank 2 Unit 1	4 ranked fixes
P2EAE	Reductant Injection Valve Circuit Range/Performance Bank 1 Unit 2	4 ranked fixes
P2EAF	Reductant Injection Valve Stuck Closed Bank 1 Unit 2	4 ranked fixes
P2EB9	Reductant Injection Valve Circuit Range/Performance Bank 2 Unit 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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