U0594 code meaning
Invalid Data Received From Hybrid/EV Powertrain Control Module
Network system Generic code U05xx codes Check engine light
What U0594 means
The hybrid or EV powertrain controller coordinates engine, motors and battery, so many modules read its messages. Ford's hybrid OBD summary explains that the ABS module logs U0594 when wheel-torque or driver-demand signals from the HPCM are flagged invalid, unknown or faulted; Ford's 2014 list carries it with MIL and its 2024 summary sets U0594_48 for bad monitoring data with MIL and wrench lamp. GM's 2023 brake tables expect serial data 31 from the module and set U0594, Type B, after 20 consecutive wrong authentication codes or a frozen alive counter. FCA names it implausible data from the HCP: on the 2020–21 Ram 1500 eTorque a poorly seated motor-generator connector led to stalling and a new MGU. Ford also found harmless U0594 entries in the Escape cluster and Lightning heat pump valve module.
U0594 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of U0594
- Check engine light and hybrid or electrical system warning
- Reduced power or stalling on some hybrids
- Stored code without symptoms (Ford Escape, F-150 Lightning)
Common causes of U0594
- Most likelyFault inside the hybrid system makes the controller mark its signals invalid (e.g. MGU connector on Ram eTorque)
- Most likelySoftware of the hybrid controller or the receiving module out of date
- Less likelyCAN wiring or termination disturbed
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Hev ev powertrain module
What each part of U0594 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 94 | The exact fault in that area. |
What to do next
- Note U0594 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 U0594
What does U0594 mean?
U0594 means "Invalid Data Received From Hybrid/EV Powertrain Control Module". The hybrid or EV powertrain controller coordinates engine, motors and battery, so many modules read its messages. It is a generic code, so it means the same on every make.
Is it safe to drive with U0594?
Drive gently and only to a workshop. With U0594 the car can go into limp mode (reduced power) to protect itself.
Will U0594 fail an emissions test?
Yes, it can. U0594 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 U0594 to fix?
Difficulty: hard. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will U0594 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.