U1900: CAN Communication Bus Fault
3 vehicles · 2 makes · $250-$1,500 repair
Most Reported On
U1900 is an OBD-II diagnostic trouble code meaning “CAN Communication Bus Fault.” U1900 is a manufacturer-specific network code (commonly Ford) indicating a CAN communication bus fault, often a receive error. The CAN bus is the high-speed network that lets control modules such as the powertrain computer, ABS module, and instrument cluster share data. This code is set when a module stops receiving expected messages from one or more modules on the bus. Because so many systems depend on the network, a bus fault can trigger multiple warning lights and erratic behavior across systems. This code is most commonly reported on 2021-2025 Ford Mustang Mach-E, 2003-2011 Saab 9-3 (Linear, Arc, Vector, Aero), and 2005-2010 Ford Mustang, with repair costs ranging from $250 to $1,500.
Common Causes
Typical Repair Cost
Based on 3 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose U1900, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (3)
FAQ
What does U1900 mean?
U1900 stands for "CAN Communication Bus Fault." U1900 is a manufacturer-specific network code (commonly Ford) indicating a CAN communication bus fault, often a receive error. The CAN bus is the high-speed network that lets control modules such as the powertrain computer, ABS module, and instrument cluster share data. This code is set when a module stops receiving expected messages from one or more modules on the bus. Because so many systems depend on the network, a bus fault can trigger multiple warning lights and erratic behavior across systems.
What are the most common causes of U1900?
The most common causes of U1900 are: Damaged, corroded, or loose CAN wiring/connectors, A failed or offline module pulling down the bus, Short to power or ground on a CAN line, Open circuit or broken CAN harness, Failed instrument cluster or ABS/PCM module, Low system voltage or weak battery, Water intrusion into a connector or module. The specific cause varies by vehicle.
How much does it cost to fix U1900?
Repair costs for U1900 range from $250 to $1,500, depending on the vehicle and root cause.
Which vehicles are affected by U1900?
Au7o has documented U1900 across 3 vehicle models from 2 manufacturers: Ford, Saab.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.