P1955 on 2024-2026 Chevrolet Corvette (E-Ray, E-Ray 1LZ, E-Ray 2LZ, E-Ray 3LZ) — Transmission Fluid Pressure Relief Valve Performance
1 vehicles · 1 makes · $350-$900 repair
Most Reported On
P1955 is an OBD-II diagnostic trouble code meaning “Transmission Fluid Pressure Relief Valve Performance.” Set in the Transmission Control Module when the commanded state of the transmission fluid pressure relief valve does not produce the expected hydraulic pressure response. On the C8 Corvette E-Ray's dual-clutch transmission, GM attributes this to auxiliary pump cavitation caused by a restricted transmission pan fluid filter: the starved pump cannot maintain pressure, so the TCM sees the relief valve circuit as underperforming. It typically sets alongside P0867 (Transmission Fluid Pressure Performance). GM explicitly directs technicians to replace the transmission pan fluid filter and to attempt no other repair for these codes. This code is most commonly reported on 2024-2026 Chevrolet Corvette (E-Ray, E-Ray 1LZ, E-Ray 2LZ, E-Ray 3LZ), with repair costs ranging from $350 to $900.
Common Causes
Typical Repair Cost
Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
P1955 does not use the standard P/B/C/U prefix. It may be a manufacturer-specific code, so verify that a scanner supports your exact year, model and module before buying.
FAQ
What does P1955 mean?
P1955 stands for "Transmission Fluid Pressure Relief Valve Performance." Set in the Transmission Control Module when the commanded state of the transmission fluid pressure relief valve does not produce the expected hydraulic pressure response. On the C8 Corvette E-Ray's dual-clutch transmission, GM attributes this to auxiliary pump cavitation caused by a restricted transmission pan fluid filter: the starved pump cannot maintain pressure, so the TCM sees the relief valve circuit as underperforming. It typically sets alongside P0867 (Transmission Fluid Pressure Performance). GM explicitly directs technicians to replace the transmission pan fluid filter and to attempt no other repair for these codes.
What are the most common causes of P1955?
The most common causes of P1955 are: Restricted or clogged transmission pan fluid filter causing auxiliary pump cavitation (GM's stated cause on 2024-2026 Corvette E-Ray), Low transmission fluid level or aerated fluid, Auxiliary/electric transmission fluid pump performance degradation, Pressure relief valve or valve body solenoid sticking, Debris circulating in the transmission hydraulic circuit. The specific cause varies by vehicle.
How much does it cost to fix P1955?
Repair costs for P1955 range from $350 to $900, depending on the vehicle and root cause.
Which vehicles are affected by P1955?
Au7o has documented P1955 across 1 vehicle models from 1 manufacturers: Chevrolet.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.