ECM-940A: Engine Control Module Fault (Volvo)
ECM-940A is an OBD-II diagnostic trouble code meaning “Engine Control Module Fault (Volvo).” Volvo-specific engine control module diagnostic code. Indicates an ECM-detected performance issue. According to Au7o's database, this code appears across 1 vehicle models from 1 manufacturers, with repair costs ranging from $200 to $800. Full vehicle-specific causes and solutions at au7o.io.
Common Causes
Typical Repair Cost
Range based on 1 documented vehicle-specific issues. Actual cost depends on the root cause, your vehicle, and whether you DIY or visit a shop.
Diagnostic Tools
To diagnose ECM-940A, 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 by ECM-940A
Click any vehicle to see the full issue details, symptoms, and repair guide.
Related Codes
Frequently Asked Questions
What does ECM-940A mean?
ECM-940A stands for "Engine Control Module Fault (Volvo)." Volvo-specific engine control module diagnostic code. Indicates an ECM-detected performance issue.
What are the most common causes of ECM-940A?
The most common causes of ECM-940A are: ECM internal fault, Sensor input error, Software update needed, Wiring issue, Environmental condition affecting sensor. The specific cause varies by vehicle — Au7o documents vehicle-specific causes for 1 models.
How much does it cost to fix ECM-940A?
Repair costs for ECM-940A range from $200 to $800, depending on the specific vehicle and root cause. Some fixes like cleaning a MAF sensor are under $50, while others like replacing a catalytic converter can exceed $2,000.
Which vehicles are affected by ECM-940A?
Au7o has documented ECM-940A across 1 vehicle models from 1 manufacturers: Volvo. See the full list below for vehicle-specific causes and repair costs.
Get a DIY Repair Guide for Your Vehicle
AI-powered step-by-step repair and maintenance guides tailored to your exact vehicle. Enter your year, make, and model to get started.
Get Started Free