P1788 – Audi DTC

Audi DTC P1788 – Reversing Light Circuit Short to B+

DTC P1788 meaning on Audi

DTC P1788 on an Audi indicates a fault in the reversing light circuit where there is a short to battery positive (B+). This means that there is an unintended connection between the reversing light circuit and the battery positive, causing a malfunction in the system.

Audi DTC P1788 symptoms

Symptoms of DTC P1788 on an Audi may include:

  • Reversing lights not working
  • Reverse gear indicator not lighting up
  • Check Engine Light (CEL) illuminated on the dashboard

Audi DTC P1788 causes

Common causes of DTC P1788 on an Audi include:

  • Short circuit in the reversing light wiring
  • Faulty reversing light switch
  • Corrosion or damage to the wiring harness

Audi DTC P1788 seriousness

While DTC P1788 is not a critical issue that affects the drivability of the Audi, it is important to address it promptly to ensure the proper functioning of the reversing lights. Ignoring this fault may lead to safety concerns, especially when reversing in low-light conditions.

How to diagnose DTC P1788 on Audi

To diagnose DTC P1788 on an Audi, follow these steps:

  1. Use a diagnostic scanner to retrieve the fault code
  2. Inspect the reversing light circuit for any visible damage or corrosion
  3. Check the reversing light switch for proper operation
  4. Perform a continuity test on the wiring harness

How to fix DTC P1788 on Audi

To fix DTC P1788 on an Audi, you can:

  1. Repair any damaged wiring in the reversing light circuit
  2. Replace the reversing light switch if faulty
  3. Clean or replace any corroded connectors in the circuit
  4. Clear the fault code and test the reversing lights for proper operation

How to erase DTC P1788 on Audi

To erase DTC P1788 on an Audi, you can:

  1. Use a diagnostic scanner to clear the fault code
  2. Ensure that the underlying issue causing the fault has been resolved
  3. Perform a test drive to confirm that the reversing lights are functioning correctly

Recommended tools for Audi diagnostics

Explore our expert picks: The Best OBD2 Scanners for 2025

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.