U023C — Lost Communication With Image Processing Module "C"

U023C — Lost Communication With Image Processing Module "C". A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: corroded connectors, especially in wet areas, a faulty module pulling the bus down, water ingress in harness junctions.

vehicle network

Is it safe to drive?

Drive with caution Depends on what is affected. A single dead convenience module is fine to drive with; loss of communication with engine, braking or steering modules is not. If multiple critical systems drop out, do not drive.

How to diagnose with an OBD scanner

  1. Read the code and freeze frame Connect an OBD2 scanner, confirm U023C is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
  2. Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many U0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
  3. Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the vehicle network (CAN bus) communication for damage, corrosion, chafing or poor contact.
  4. Subsystem check Measure resistance between CAN-High and CAN-Low at the OBD port with power off — about 60 Ω is healthy.
  5. Subsystem check Scan all modules: the one that does not respond is either the culprit or downstream of the break.
  6. Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm U023C does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for U023C (parts and labor, USD, independent shop rates): Remove interfering aftermarket device: $0–$150; Repair CAN wiring or connectors: $100–$400; Replace the faulty control module: $300–$1,500. Overall, fixing U023C usually costs between $0 and $1,500. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

What is the most common cause of U023C?

The most common causes are: corroded connectors, especially in wet areas, a faulty module pulling the bus down, water ingress in harness junctions.

What does OBD2 code U023C mean?

U023C — Lost Communication With Image Processing Module "C". A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: corroded connectors, especially in wet areas, a faulty module pulling the bus down, water ingress in harness junctions.

How much does it cost to fix U023C?

Remove interfering aftermarket device — $0–$150; Repair CAN wiring or connectors — $100–$400; Replace the faulty control module — $300–$1,500. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

Will U023C clear itself?

Sometimes U023C clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

How do I diagnose U023C myself?

Start with a scan: confirm U023C, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the vehicle network (CAN bus) communication, and verify the suspect component against live data before buying parts.

What does U023C mean?

Seeing U023C on your scanner? The control unit has caught the vehicle network (CAN bus) communication operating outside its calibrated window. The formal description is “Lost Communication With Image Processing Module "C"”, and the code is grouped under vehicle network faults.

To set U023C, the control module compares live readings of the vehicle network (CAN bus) communication against calibrated limits, usually over several drive cycles. Alongside the code it stores a freeze frame — a snapshot of rpm, load, coolant temperature and vehicle speed at the moment of failure. Reading that snapshot first saves diagnostic time.

Common symptoms of U023C

  • no-start or intermittent starting in some cases
  • multiple warning lights on at once
  • random, hard-to-reproduce electrical glitches
  • intermittent loss of functions (gauges, windows, steering assist)
  • modules intermittently not communicating with the scanner

What causes U023C?

  • damaged CAN bus wiring or short to power/ground
  • corroded connectors, especially in wet areas
  • poor grounds or low battery voltage
  • aftermarket equipment interfering with the bus
  • water ingress in harness junctions
  • a faulty module pulling the bus down

How to diagnose U023C

  1. Connect an OBD2 scanner, confirm U023C is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
  2. Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many U0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
  3. Visually inspect the wiring harness and connectors related to the vehicle network (CAN bus) communication for damage, corrosion, chafing or poor contact.
  4. Measure resistance between CAN-High and CAN-Low at the OBD port with power off — about 60 Ω is healthy.
  5. Scan all modules: the one that does not respond is either the culprit or downstream of the break.
  6. Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm U023C does not return.

How to fix U023C

Start with the cheapest and most common causes before replacing expensive parts:

  • Remove interfering aftermarket device — $0–$150
  • Repair CAN wiring or connectors — $100–$400
  • Replace the faulty control module — $300–$1,500

How much does it cost to fix U023C?

Repair cost depends on which component actually failed. Typical scenarios for U023C (parts and labor, USD, independent shop rates):

  • Remove interfering aftermarket device: $0–$150
  • Repair CAN wiring or connectors: $100–$400
  • Replace the faulty control module: $300–$1,500

Overall, fixing U023C usually costs between $0 and $1,500. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Can you drive with U023C?

Depends on what is affected. A single dead convenience module is fine to drive with; loss of communication with engine, braking or steering modules is not. If multiple critical systems drop out, do not drive.

Related OBD2 codes