Engine-Codes - Generic - U1121

U1121 - Lost Communication With Electric Stability Program Module

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

U1121 Possible Causes

  • Faulty Electronic Stability Control (ESC) Module
  • Electronic Stability Control Module harness is open or shorted
  • Electronic Stability Control Module circuit poor electrical connection

How is the U1121 code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the U1121 code

Labor: 1.0

The cost to diagnose the U1121 code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

U1121 Meaning

Several control units are applied to electronically controlled vehicles. These units perform each control with information from various sensors. Thus, sharing signal information from sensors is needed, so CAN communication type whose communication speed is high and insensitive to electrical noise by spark generation is adopted to controlling powertrain (TCM, ECM, CLUSTER, Electronic Stability Control (ESC), 4WD, SAS, EPS). CAN communication consists of CAN-BUS HIGH, CAN BUS LOW, and two 120 ohm resistance in the circuit. If the 4WD ECU doesn't get some ESC signals from the ESC module, it sets U1126.

More Information

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Information for specific makes

  • U1121 HYUNDAI Lost Communication With Electric Stability Program Module
  • U1121 KIA Lost Communication With Electric Stability Program Module

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