Fault Family System: Powertrain (P-Codes) 10 SAE Codes

Engine Cooling Fan Performance

Diagnostic & Technical Explanation

Code P2B2F (Fan 1 Performance/Stuck Off) sets when a numbered engine cooling fan is commanded on or off and its actual airflow, current draw, or speed feedback does not match the command - stuck off, stuck on, or running at the wrong speed. Causes are a seized fan motor bearing, a relay welded closed or open, a failed fan speed controller, or debris jamming the fan blade.

These 10 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 10 times.

Codes in this family (10)

Code	Definition	Repair coverage
P2B2F	Fan 1 Performance/Stuck Off	4 ranked fixes
P2B30	Fan 1 Stuck On	4 ranked fixes
P2B31	Fan 2 Performance/Stuck Off	4 ranked fixes
P2B32	Fan 2 Stuck On	4 ranked fixes
P2C41	Fan 3 Performance/Stuck Off	4 ranked fixes
P2C42	Fan 4 Performance/Stuck Off	4 ranked fixes
P2CB9	Fan 2 Underspeed	4 ranked fixes
P2CBA	Fan 2 Overspeed	4 ranked fixes
P2CBB	Fan 3 Underspeed	4 ranked fixes
P2CBC	Fan 3 Overspeed	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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