Engine Control Module Communication Loss
Indicates a communication failure with the engine control module (ECM).
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
This code means your vehicle's computer isn't talking correctly to the engine control module, which can lead to problems controlling engine functions like fuel and ignition.
What the computer is actually seeing
The onboard computer detects no valid data messages from the ECM after multiple attempts within a specified time frame, usually around 200 ms of expected communication intervals.
What a healthy reading looks like
Expect typical communication data transfer rates, from the ECM to the vehicle's multiplex network, to be stable within 50-100ms.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the battery voltage—should be above 12.6V with the engine off and 13.5-14.5V with the engine running.
- 2Inspect the wiring harness and connectors between the ECM and the vehicle's multiplex system for any signs of damage or corrosion. Repair as necessary.
- 3Use a scan tool to check for other related codes. If there are additional codes, address those issues first, as they could be causing the communication failure.
- 4Try resetting the ECM by disconnecting the battery for 10 minutes. Reconnect and see if the code returns. If it does, further diagnose the ECM itself.
Common causes
- Damaged wiring or connectors between the ECM and vehicle bus
- Faulty ECM
- Corrosion or dirt in connectors
- Software issues in the engine control module
- Low battery voltage affecting communication
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's advised to fix this soon; while it may drive, you'll lose engine performance and efficiency.
Will the code come back after clearing it?
If the underlying issue isn't fixed, yes, it will likely return.
Why does it pair with other SPN codes?
Multiple codes often indicate a systemic issue affecting communications between multiple components, not just the ECM.
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