Fault Family System: Powertrain (P-Codes) 4 SAE Codes

DPF Differential Pressure

Diagnostic & Technical Explanation

Code P244A (Particulate Filter Differential Pressure Too Low Bank 1) sets when the pressure drop measured across the DPF is implausibly low for the exhaust flow rate, suggesting the filter substrate is cracked or missing, or implausibly high, suggesting the filter is more restricted than the soot-load model predicts. A melted or cracked substrate letting exhaust bypass the filtering media causes the low-pressure fault, while a partially melted/collapsed filter or unexpected ash bridging causes the high-pressure fault.

These 4 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 4 times.

Codes in this family (4)

Code	Definition	Repair coverage
P244A	Particulate Filter Differential Pressure Too Low Bank 1	3 ranked fixes
P244B	Particulate Filter Differential Pressure Too High Bank 1	3 ranked fixes
P2464	Particulate Filter Differential Pressure Too Low Bank 2	3 ranked fixes
P2465	Particulate Filter Differential Pressure Too High Bank 2	3 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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