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P1A8B00 — Refrigerant circuit shut-off valve (EAV5) – part number implausible

Refrigerant circuit shut-off valve (EAV5) – part number implausible. The Taycan, 911 (992), Panamera (971), Panamera (972) and Cayenne report this code; below is which control unit sets it on each model and how to read and clear it.

Which models and control units set P1A8B00

Porsche Taycan

Porsche 911 (992)

Porsche Panamera (971, 2017–2023)

Porsche Panamera (972, 2024–)

Porsche Cayenne (9YA)

How to read and clear P1A8B00

  1. Plug a standard ENET (Ethernet-to-OBD) cable into your Porsche's OBD port and your Mac or Windows PC.
  2. Open STEUER14, pick your car and run a fault scan: every control unit is read, and P1A8B00 shows with its status, its full description and the freeze frame when the unit stores one.
  3. Fix the cause first, then clear the fault memory and scan again to check it stays away. Reading and clearing fault codes is free on every control unit.

More about fault memory in the manual →

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Other codes of the Thermal Management

P1A8100Cooling system drain and fill/check function – active
P1A8200Refrigerant circuit sensor on high-pressure side - pressure too high
P1A8300Camshaft adjustment, Replacement reaction active
P1A8700Refrigerant circuit shut-off valve (EAV2) – part number implausible
P1A8900Refrigerant circuit shut-off valve (EAV3) – part number implausible
P1A8A00Valve 3 for refrigerant, Incorrect component installed
P1A8C00Refrigerant circuit shut-off valve (EAV2) – not taught
P1A8D00Refrigerant circuit shut-off valve (EAV3) – not taught
P1A8E00Valve 3 for refrigerant, wrong address
P1A8F00Refrigerant circuit shut-off valve (EAV5) – not taught
P1A9000Sensors for refrigerant circuit (PT1/PT2/PT3) – pressure signal deviation too large
P1B5B00Directional-control valve for high-temperature circuit (WMV1) – temperature implausible

All 636 codes of this control unit →

Fault names come from the manufacturer's diagnostic data. STEUER14 is independent and not affiliated with Porsche AG. A code tells you what a control unit detected, not always which part failed — check wiring, supply voltage and related codes before replacing parts. STEUER14 shows each fault's full description, status and freeze frame on the car.