Fault Family System: Powertrain (P-Codes) 8 SAE Codes

HV Battery Precharge Contactor

Diagnostic & Technical Explanation

Code P0AE1 sets when the battery management system commands the HV battery pack's precharge contactor — the small auxiliary contactor that routes current through a current-limiting resistor before the main contactors close — open or closed, and its feedback contact or the resulting bus-voltage ramp does not confirm the commanded state. Because this contactor only carries the limited precharge current rather than full pack current, the most common physical causes are a coil winding failure, a corroded coil-driver connector, and, unlike the main contactors, contact erosion from the repeated low-energy arcing that is normal for this contactor's duty cycle rather than high-current welding.

These 8 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 8 times.

Codes in this family (8)

Code	Definition	Repair coverage
P0AE1	Hybrid/EV Battery Precharge Contactor Circuit	3 ranked fixes
P0AE2	Hybrid/EV Battery Precharge Contactor Circuit Stuck Closed	3 ranked fixes
P0AE3	Hybrid/EV Battery Precharge Contactor Circuit Stuck Open	3 ranked fixes
P0AE4	Hybrid/EV Battery Precharge Contactor A Control Circuit/Open	3 ranked fixes
P0AE5	Hybrid/EV Battery Precharge Contactor A Control Circuit Range/Performance	3 ranked fixes
P0AE6	Hybrid/EV Battery Precharge Contactor A Control Circuit Low	3 ranked fixes
P0AE7	Hybrid/EV Battery Precharge Contactor A Control Circuit High	3 ranked fixes
P2C89	Hybrid/EV Battery System Precharge Current Too High	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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