U0158low severityNetwork
Lost Communication with Head-Up Display Module
on 2019 Audi A6 2.0L Turbo I4 · AWD
What this code means
Cannot communicate with the head-up display (HUD) projector module.
Symptoms
- HUD not projecting
- HUD display blank
- HUD settings not accessible
- HUD warning message
Common causes
- HUD module failure
- CAN bus wiring
- Module power loss
- Fuse blown
- HUD projector lamp failure
Diagnostic steps
- Check HUD module fuse
- Test power and ground
- Check CAN wiring
- Inspect HUD projector unit
- Test with diagnostic tool
Repair notes
Check fuses. HUD projector units can fail from heat exposure on dash.
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00003
Control Module - Defective
01304
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01312
Powertrain Data Bus - Defective
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U0001
High Speed CAN Communication Bus