OBD Guide

U1204

IMA-CAN Malfunction

U1204 is an OBD-II diagnostic trouble code meaning: IMA-CAN Malfunction. Common causes: broken or damaged can bus wires, poor contact in connectors. Estimated repair cost: $6–56.

Severity
🔴 High
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$6–56 (est.)

Symptoms

  • Check Engine light comes on
  • The car goes into emergency mode
  • Malfunctions of various systems
  • Gear shifting problems
  • Reduced engine power

Causes

  • Broken or damaged CAN bus wires
  • Poor contact in connectors
  • Malfunction of one of the electronic modules
  • Short circuit in the circuit
  • Problems with module power supply

How to Fix

  1. Check the integrity of the CAN bus wiring
  2. Inspect all connectors for oxidation or damage.
  3. Check power supply and ground of connected modules
  4. Scan all modules for errors
  5. Replace damaged wires or connectors

Related codes

FAQ

What does the U1204 code mean?

U1204 is an OBD-II diagnostic trouble code that indicates: IMA-CAN Malfunction

What causes a U1204 error code?

The most common causes of U1204 include: Broken or damaged CAN bus wires; Poor contact in connectors; Malfunction of one of the electronic modules; Short circuit in the circuit.

How do I fix a U1204 diagnostic trouble code?

To fix U1204: Check the integrity of the CAN bus wiring. Inspect all connectors for oxidation or damage.. Check power supply and ground of connected modules. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U1204?

Do not drive — repair immediately

How much does it cost to fix U1204?

The estimated repair cost for U1204 is $6–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat