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ECM-940AModerateEngine

ECM-940A: Engine Control Module Fault (Volvo)

1 vehicles · 1 makes · $200-$800 repair

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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. This code appears across 1 vehicle models from 1 manufacturers, with repair costs ranging from $200 to $800.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
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Common Causes

1ECM internal fault
2Sensor input error
3Software update needed
4Wiring issue
5Environmental condition affecting sensor

Typical Repair Cost

$200 - $800

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose ECM-940A, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

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
Check Price on Amazon
Best Value$90–$120

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)
Check Price on Amazon
Advanced$180–$230

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
Check Price on Amazon
Professional$350–$450

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
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (1)

Related Codes (8)

002FManufacturer-Specific Diagnostic Code16566Mass Air Flow Sensor Signal Too Low (VAG)P0008Engine Position System Performance - Bank 1P0009Engine Position System Performance - Bank 2P0010Intake Camshaft Position Actuator Circuit (Bank 1)P0011Intake Camshaft Position Timing - Over-Advanced (Bank 1)P0012Intake Camshaft Position Timing - Over-Retarded (Bank 1)P0014Exhaust Camshaft Position Timing - Over-Advanced (Bank 1)

FAQ

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.

How much does it cost to fix ECM-940A?

Repair costs for ECM-940A range from $200 to $800, depending on the vehicle and root cause.

Which vehicles are affected by ECM-940A?

Au7o has documented ECM-940A across 1 vehicle models from 1 manufacturers: Volvo.

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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