Updated: 12 August 2026.
OEM PT4G is a Porsche diagnostic interface for supported PIWIS Tester IV workflows. It is a separate hardware generation from PT3G-E V2 and VNCI PT3G, with its own supported VCI and update path.
Obtain the PT4G components
Install the supported PIWIS IV environment and PT4G interface components provided through the authorized Porsche workshop/update route or the verified order package. Do not reuse PT3G firmware simply because both devices operate with PIWIS.
OEM PT4G installation
- Confirm the PT4G hardware label and close PIWIS.
- Install the supported PIWIS IV/VCI components and restart when requested.
- Connect PT4G using the supplied wired method for first setup.
- Verify its model, serial information and connection state inside PIWIS.
- Allow a required PT4G update to complete while the tester remains on external power.
- Reopen PIWIS and confirm that PT4G is available.
- Connect to the vehicle with battery support and perform identification before programming.
PT4G online update
Porsche support documentation describes online updates for PIWIS Tester IV. Downloads can occur when the registered tester is online, while installation must be started from the PIWIS update function. Keep the tester on external power and do not interrupt the installation or restart.
Troubleshooting OEM PT4G
- Interface not listed: check wired connectivity, VCI components and tester network.
- Update unavailable: verify PIWIS registration, account entitlement and Internet access separately.
- Firmware mismatch: stop and obtain the PT4G package; never cross-flash PT3G firmware.
- Vehicle connection fails: confirm PT4G is available in PIWIS, then check OBD and voltage.
- Programming interruption risk: change to a stable wired link before starting.
OEM PT4G product
View the OEM PT4G Diagnostic Tool. Other Porsche interfaces have their own guides: OEM PT3G-E V2 and VNCI PT3G.
Safety: Maintain tester power, wired communication and regulated vehicle voltage throughout updates and programming.