U301B

Control Module Wake-up Circuit A Low

Severity

⚠️ Medium

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$17–89 (est.)

Symptoms

Engine won't start
Intermittent electronic failures
Check Engine Light Is On
The module does not respond during diagnostics
Random malfunctions in vehicle systems

Causes

Broken or damaged wires in the wake-up circuit
Poor contact in module connectors
Short circuit to ground
Faulty relay or fuse
Problems with the control module itself

How to Fix

Check the integrity of fuses and relays
Inspect the wiring harness for damage
Check the quality of contacts in the module connectors
Diagnose wake-up circuit resistance
Check the control module itself for faults

Related codes

U3000 U301A U301F