U0103 on RAM
Lost Communication With Gear Shift Control Module "A"
U0103 on RAM vehicles indicates lost communication with gear shift control module "a". Au7o has documented this code across 1 RAM model — most commonly on 1500. Sets when a module loses data-bus communication with the Gear Shift Control Module 'A' (electronic/shift-by-wire gear selector) and no longer receives its expected messages. Common on vehicles with electronic shifters. Typical repair costs on RAM range from $300 to $900, depending on the specific model and root cause.
Common Causes of U0103
- •Open, shorted, or chafed bus wiring to the shift control module
- •Corroded or loose shift module connector
- •Blown fuse / lost power or ground to the module
- •Low battery voltage
- •Failed gear shift control module
U0103 on RAM by Model
RAM 1500(1 issue)
- Transfer Case Shift Motor / Actuator Failure ('Service 4WD', Won't Engage 4-High or 4-Low)2011-2023
4WD-equipped Ram 1500 trucks use an electric shift motor (encoder/gear motor) bolted to the BorgWarner transfer case to move between 2WD, 4WD-Auto, 4-High and 4-Low. The motor's internal plastic gears wear or strip, and water/road-salt intrusion corrodes the connector and motor windings, so the system fails to complete a shift. The dash shows 'Service 4WD,' the mode indicator blinks without engaging, and grinding or clicking can be heard from under the truck. A large share of Ram 4WD-engagement complaints trace to the shift motor rather than internal transfer-case damage, so it is usually a relatively affordable fix if caught early. FCA TSB 08-094-20 provides a Drivetrain Control Module (DTCM) software update for 2016-2020 trucks with this symptom.
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View U0103 across all makes →Frequently Asked Questions
What does U0103 mean on RAM?▼
U0103 stands for "Lost Communication With Gear Shift Control Module "A"." Sets when a module loses data-bus communication with the Gear Shift Control Module 'A' (electronic/shift-by-wire gear selector) and no longer receives its expected messages. Common on vehicles with electronic shifters. On RAM specifically, this code is documented across 1 model.
What causes U0103 on RAM vehicles?▼
Common causes on RAM: Open, shorted, or chafed bus wiring to the shift control module, Corroded or loose shift module connector, Blown fuse / lost power or ground to the module, Low battery voltage, Failed gear shift control module. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix U0103 on a RAM?▼
Repair costs on RAM range from $300 to $900, depending on the specific model and root cause.
Which RAM models have U0103 documented?▼
Au7o has documented U0103 on 1 RAM model: 1500.