U0121 on Dodge
Lost Communication with ABS Module
U0121 on Dodge vehicles indicates lost communication with abs module. Au7o has documented this code across 1 Dodge model — most commonly on Magnum. U0121 is a network communication code meaning a control module on the vehicle's data bus has lost communication with the ABS (anti-lock brake system) module. Modern cars share information over a CAN bus, and when other modules stop receiving expected messages from the ABS unit, this code sets. Because the ABS module also handles traction control and stability control on most vehicles, you may see multiple warning lights and lost features. It points to a communication or power problem with the ABS module rather than a worn brake part. Typical repair costs on Dodge range from $100 to $800, depending on the specific model and root cause.
Common Causes of U0121
- •Loss of power or ground to the ABS module
- •Blown fuse feeding the ABS controller
- •Damaged, corroded, or loose ABS module connector
- •Open, shorted, or chafed CAN bus wiring
- •Internal failure of the ABS control module
- •Corrosion or water intrusion in connectors/harness
- •Faulty gateway module disrupting bus communication
U0121 on Dodge by Model
Dodge Magnum(1 issue)
- Electrical System Flickering, Dash Light Failures, and Steering Column Module Issues2005-2008
The Dodge Magnum suffers from widespread electrical problems centered around the TIPM (Totally Integrated Power Module) and the steering column control module (clockspring). Symptoms include dash lights flickering or going completely dark while driving, headlights cutting out at night, loss of turn signals, wipers, horn, and cruise control all at once. The steering column module failure is particularly dangerous as it can disable multiple safety systems simultaneously. The TIPM relay failures can cause no-start conditions, fuel pump cutouts, and random electrical gremlins throughout the vehicle.
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What does U0121 mean on Dodge?▼
U0121 stands for "Lost Communication with ABS Module." U0121 is a network communication code meaning a control module on the vehicle's data bus has lost communication with the ABS (anti-lock brake system) module. Modern cars share information over a CAN bus, and when other modules stop receiving expected messages from the ABS unit, this code sets. Because the ABS module also handles traction control and stability control on most vehicles, you may see multiple warning lights and lost features. It points to a communication or power problem with the ABS module rather than a worn brake part. On Dodge specifically, this code is documented across 1 model.
What causes U0121 on Dodge vehicles?▼
Common causes on Dodge: Loss of power or ground to the ABS module, Blown fuse feeding the ABS controller, Damaged, corroded, or loose ABS module connector, Open, shorted, or chafed CAN bus wiring, Internal failure of the ABS control module. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix U0121 on a Dodge?▼
Repair costs on Dodge range from $100 to $800, depending on the specific model and root cause.
Which Dodge models have U0121 documented?▼
Au7o has documented U0121 on 1 Dodge model: Magnum.