ABS Module Lab

C121E

ABS / stability-control fault code, listed for 1 vehicle line from Dodge. What it means on each one, with sources, and when the module is the cause.

What C121E means

Is it the ABS module?

Check the cheap things first: battery voltage and the main fuses for the ABS pump and module, the ground straps, the module connector (corrosion, a pushed-back pin) and, for wheel-speed codes, the sensor and its wiring at each wheel. If those are good and the code returns as soon as it is cleared — or the scan tool cannot talk to the ABS module at all — the module itself is the likely cause, and that is what we repair.

Vehicles that set C121E

C121E by vehicle

What does C121E mean on a Dodge Durango (HB)?

The source we cite for the 2004-2009 Dodge Durango (HB) lists it as: Brake Pressure Transmitter - a rebuilder fault text for a Dodge DURANGO 2006 - 2009 listing. That vehicle uses Bosch (2007-2009 per rebuilders) Bosch 8.0 - a rebuilder 'Bosch 8.0 ... Dodge ... ABS Rebuild' lists 2007-2009 Dodge Durango and 2007 Chrysler Aspen; C. We repair it as part of the Bosch ABS / ESP 8 family, from $499.

Still not sure?

Send us C121E, a photo of the module label and your VIN — we tell you whether the module is the likely cause and what it costs, before you pull anything. Asking costs nothing.

C121E keeps coming back after the checks? Fix the module — from $499.

Look up your part number and order online — we email you a prepaid label to our lab. Or send us a photo of the label and your VIN first, and we'll tell you what you have and what it costs.

Back with your VIN and coding · can’t be repaired? repair price back, minus shipping · 1-year warranty · rush 2–3 days +$100

Call (817) 505-4201 · 📱 Text us a photo of the module label · Ask first — send a label photo · Email repairs@absmodulelab.com