U301D code meaning
Control Module Wake-up Circuit A Performance
Network system Generic code U30xx codes Check engine light
What U301D means
U301D says wake-up line A is electrically intact but its level does not fit what the module expects at that moment. Ford uses it in the battery energy control module of the 2019 Fusion Energi plug-in hybrid. Its OBD summary files the code under the charging performance checks: while the charger is precharging and its output voltage is already within the window for closing the charge contactors, the BECM still sees the charge wake-up line low before it has asked for the contactors to close. Ford's TSB 18-2386 and SSM 47630 report U301D with a lit MIL after charging on cars built up to 2 Oct 2018; if it is the only BECM code, the PCM and BECM are reprogrammed together (0.5 h) under the emissions warranty. Charging is normally unaffected, but the MIL stays on until cleared.
U301D at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor0.5 to 1 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U301D
- MIL on after a charging session
- Code is the only entry in the battery control module
Common causes of U301D
- Most likelyBECM and PCM software judging the wake-up timing too strictly
- PossibleOn-board charger raising its wake-up signal late or unsteadily
- Less likelyHigh resistance in the charge wake-up wire or connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Wakeup circuit aBattery energy control moduleOn board charger
What each part of U301D means
| U | Network system: communication between the control modules (CAN bus). |
| 3 | Reserved range, usually generic. |
| 1D | The exact fault in that area. |
What to do next
- Note U301D and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U301D
What does U301D mean?
U301D means "Control Module Wake-up Circuit A Performance". U301D says wake-up line A is electrically intact but its level does not fit what the module expects at that moment. It is a generic code, so it means the same on every make.
Is it safe to drive with U301D?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will U301D fail an emissions test?
Yes, it can. U301D is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is U301D to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 1 hours of work. This is a job for a workshop.
Will U301D clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.