U040E: Invalid Data Received From Turbocharger/Supercharger Control Module B

What it means

A control module received data from Turbocharger/Supercharger Control Module B that it judged invalid or implausible. This code identifies the rejected data, but does not by itself identify the cause.

At a glance

• Usually lights the warning light of the system that lost communication
• Affects emissions; the car can fail an emissions test
• The engine or gearbox may go into limp mode

How it works

Turbocharger/supercharger control module B sends boost-control status and related operating data to other modules over the vehicle network. U040E sets when a receiving module rejects data specifically from module B as implausible; it does not identify a fault in module A or prove that the forced-induction unit itself has failed.

Common causes

Most likely first.

1. Fault or implausible input at the sending module
2. Damaged or loose network wiring or connector
3. Module power, ground, or programming issue

Symptoms

• Warning message or warning lights
• Turbocharger or supercharger functions may be limited
• Other communication codes

How to diagnose it

1. Scan all modules and save freeze-frame data to identify the receiving module and any module B, boost-control, or network codes logged at the same time.
2. Check live data for module B status and available commanded and reported boost-control values, noting missing or inconsistent readings.
3. Inspect module B's connector and visible network wiring for loose pins, corrosion, heat damage, or chafing.
4. Check module B power and ground and test related sensor and actuator circuits against the manufacturer's specification.
5. Inspect boost-control hoses, linkage, and related hardware if live data or companion codes point to a mechanical problem.
6. If wiring and inputs are sound, verify module B software and configuration and investigate network faults using the manufacturer's diagnostic procedure.

Common fixes

• Repair damaged or loose wiring or connector terminals at turbocharger/supercharger control module B.
• Repair a failed power, ground, sensor, or actuator circuit found during testing.
• Repair a boost-control hose, linkage, or related mechanical fault confirmed by inspection.
• Correct module B software or configuration incompatibility.
• Replace module B only if testing confirms an internal fault.

Can I keep driving?

Avoid heavy acceleration, towing, or high-load driving if boost is limited or engine power is reduced. Stop if the engine makes unusual mechanical noises, smokes heavily, or becomes difficult to control.