Invalid Data Received From ECM/PCM
The U0401 code means the vehicle's onboard diagnostic system has detected: Invalid Data Received From ECM/PCM. This is a moderate severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- hard
- Estimated cost
- $100 - $800 (parts and labor)
Network codes mean modules are not communicating. You need a scanner that reads all systems to find the problem.
Check Price on AmazonAffiliate link -- we earn a commission at no extra cost to you.
Common Symptoms
- Check Engine Light illuminated
- Intermittent drivability issues
- Other modules may set related codes
- Dashboard displays incorrect information
Probable Causes (Ranked by Likelihood)
- ECM sending corrupted data on CAN bus Very High
- CAN bus signal integrity issue (noise) High
- ECM software glitch Moderate
- Electromagnetic interference from aftermarket accessories Low
Step-by-Step Diagnostic Procedure
-
Check for ECM-specific codes that may indicate the source of invalid data
-
Inspect CAN bus wiring for damage or proximity to high-current wires
-
Check for aftermarket accessories that may cause electromagnetic interference
-
Attempt ECM reflash with latest calibration
-
If CAN bus wiring is damaged, repair and retest
Common Fixes by Vehicle
What techs usually find when diagnosing U0401 on specific vehicles — tap your vehicle for the fix and the exact part:
2007-2018 Chevrolet Silverado/GMC Sierra moderate (diagnosis), hard (reflash) DIY
Invalid data received from ECM/PCM means the PCM is communicating on the CAN bus but sending corrupt data. This is usually caused by a PCM software glitch or a failing PCM. Try clearing codes and monitoring. If U0401 returns, the PCM may need a software reflash. GM dealers can check for updated calibrations. If no updates are available, the PCM itself may need replacement.
Labor: 30 min (diagnosis), 2 hours (reflash/replace)2008-2020 Ford F-150/Escape/Explorer easy DIY
U0401 on Ford vehicles can be caused by a PCM that needs a Throttle Body relearn or KAM (Keep Alive Memory) reset after a battery disconnect. Disconnect the battery for 15 minutes, reconnect, then idle the engine for 5 minutes without touching the throttle. This allows the PCM to relearn its adaptive values. If U0401 persists, the PCM may need a software update via IDS.
Labor: 15-30 min2007-2017 Chevrolet Tahoe/Suburban/Yukon moderate DIY
On GM SUVs, U0401 can appear after installing a tuner or performance programmer that modifies PCM data. If a tuner has been installed, return the PCM to stock calibration and clear codes. If no tuner is present, this code along with drivability issues usually means the PCM needs replacement. GM PCMs must be VIN-programmed after installation.
Labor: 30 min - 2 hoursFrequently Asked Questions
Can I drive with code U0401?
Drive short distances only. Lost communication codes indicate a module has stopped communicating on the vehicle network. The affected system may not function correctly.
What causes U0401?
The most common cause is a failed module or a wiring issue in the CAN bus network. ECM sending corrupted data on CAN bus is the most likely cause. Power supply, ground, and connector issues should be checked before replacing any module.
Is U0401 expensive to fix?
Repair costs range from $100 - $800 (parts and labor). Wiring repairs are on the lower end, while module replacement is on the higher end. The module may also need to be programmed after replacement.
Sources
This page is built from documented references. Verify against your own service info before repair work.
U0401 on Diesel, EV & Equipment
The same code ID appears across other engines and platforms. The diagnostic flow varies by manufacturer — these are the platform-specific breakdowns:
See All Codes & Fixes for Your Vehicle
Explore More
Was this helpful?
Share carcodefinder.com with a friend who needs to decode their check engine light.