OBD Guide
ENFRDEESPT

U1793

14V Power Module Lost Communication With Hybrid/EV Powertrain Control Module On Powertrain Expansion Communication Bus

U1793 is an OBD-II diagnostic trouble code meaning: 14V Power Module Lost Communication With Hybrid/EV Powertrain Control Module On Powertrain Expansion Communication Bus. Common causes: open or short circuit in the communication circuit between modules, 14v power module faulty. Estimated repair cost: $56–278.

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$56–278 (est.)

Symptoms

  • Check Engine light comes on
  • Reduced power or unstable operation of the hybrid system
  • Errors in other CAN bus-related systems
  • Problems with charging a 14V battery
  • The vehicle goes into emergency mode

Causes

  • Open or short circuit in the communication circuit between modules
  • 14V power module faulty
  • Problems with the hybrid transmission control unit
  • Corroded or damaged connectors
  • Problems with the CAN bus (break, short circuit)

How to Fix

  1. Check the integrity of the wiring between the modules
  2. Inspect and clean connectors from corrosion
  3. Check power and grounding of both modules
  4. Scan the CAN bus for errors
  5. Replace the faulty module if necessary

Related codes

U1794U1792U1795

FAQ

What does the U1793 code mean?

U1793 is an OBD-II diagnostic trouble code that indicates: 14V Power Module Lost Communication With Hybrid/EV Powertrain Control Module On Powertrain Expansion Communication Bus

What causes a U1793 error code?

The most common causes of U1793 include: Open or short circuit in the communication circuit between modules; 14V power module faulty; Problems with the hybrid transmission control unit; Corroded or damaged connectors.

How do I fix a U1793 diagnostic trouble code?

To fix U1793: Check the integrity of the wiring between the modules. Inspect and clean connectors from corrosion. Check power and grounding of both modules. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U1793?

Do not drive — repair immediately

How much does it cost to fix U1793?

The estimated repair cost for U1793 is $56–278. Actual cost depends on your vehicle, location, and labor rates.

FRDEESPT

See also: Russian version · NationStat