OBD Guide

U1127

Invalid Or Missing Data For Primary Id

U1127 is an OBD-II diagnostic trouble code meaning: Invalid Or Missing Data For Primary Id. Common causes: broken or damaged can bus wires, oxidation of contacts in connectors. Estimated repair cost: $6–56.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$6–56 (est.)

Symptoms

  • Check Engine Light Is On
  • There may be malfunctions in various vehicle systems
  • Loss of data on the dashboard
  • Incorrect operation of electronic assistants

Causes

  • Broken or damaged CAN bus wires
  • Oxidation of contacts in connectors
  • Malfunction of one of the ECUs
  • Software failure in the module
  • Problems with CAN bus power supply

How to Fix

  1. Check the integrity of the CAN bus with a multimeter
  2. Inspect and clean all connectors in the circuit
  3. Check CAN bus power supply
  4. Read error codes from all modules
  5. If necessary, reflash the problematic module

Related codes

FAQ

What does the U1127 code mean?

U1127 is an OBD-II diagnostic trouble code that indicates: Invalid Or Missing Data For Primary Id

What causes a U1127 error code?

The most common causes of U1127 include: Broken or damaged CAN bus wires; Oxidation of contacts in connectors; Malfunction of one of the ECUs; Software failure in the module.

How do I fix a U1127 diagnostic trouble code?

To fix U1127: Check the integrity of the CAN bus with a multimeter. Inspect and clean all connectors in the circuit. Check CAN bus power supply. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U1127?

Yes, but get it checked soon

How much does it cost to fix U1127?

The estimated repair cost for U1127 is $6–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat