U0003high severityNetwork
High Speed CAN Communication Bus (+) Open
on 2021 Porsche Taycan Turbo Electric AWD · AWD
What this code means
The CAN High wire is open, disrupting high-speed bus communication. CAN H carries the dominant high signal.
Symptoms
- Multiple modules offline
- Warning lights illuminated
- Systems inoperative
- No scan tool communication on some modules
Common causes
- Broken CAN H wire
- Corroded CAN H terminal
- Damaged CAN bus connector
- Wiring harness damage
Diagnostic steps
- Measure voltage on CAN H (should be ~2.5V idle, ~3.5V dominant)
- Check continuity of CAN H wire
- Inspect CAN bus connectors
- Locate break using voltage drop test
Repair notes
Locate and repair the open in the CAN H wire. Check all splice points.
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Other Network codes on this vehicle
00003
Control Module - Defective
01304
Radio - No Communication
01312
Powertrain Data Bus - Defective
01315
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01316
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01317
Instrument Cluster Control Module (J285) - No Communication
01318
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01321
Airbag Control Module - No Communication
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance