What it means
The control module monitors high voltage fuse C for continuity. It sets this code when the fuse is detected as open, interrupting the associated high voltage circuit.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Fuse C protects or completes a high-voltage circuit in the hybrid or EV system. The control module checks whether this fuse has continuity and sets P0E30 when it detects an open fuse, cutting power through the associated circuit.
Common causes
Most likely first.
- Fuse blown by short circuit
- Downstream short circuit
Symptoms
- Hybrid/EV system warning light may turn on
- Reduced power or charging performance
How to diagnose it
- Read freeze-frame data and related hybrid or EV fault codes first to identify when the fuse opened and whether another fault points to a short.
- With the vehicle made safe according to the manufacturer's high-voltage service procedure, inspect the accessible fuse C area and its connectors for heat damage, corrosion, or poor seating.
- Have a qualified technician test fuse C for continuity using the manufacturer's procedure; do not handle exposed high-voltage parts.
- If fuse C is open, trace the associated circuit for a short before installing a replacement, since a downstream short can blow the new fuse.
- After repairing the cause and replacing the fuse as specified, clear the code and check whether it returns during the manufacturer's prescribed system check.
Common fixes
- Correct a loose or damaged fuse C connection.
- Repair damaged wiring or a connector in the circuit protected by fuse C.
- Find and repair the downstream short that caused the fuse to open.
- Replace fuse C with the specified type after confirming the short is repaired.
Can I keep driving?
Because this fault can interrupt a high-voltage circuit and trigger reduced power or charging, avoid relying on the vehicle for normal trips. Stop safely if power drops or a hybrid/EV warning appears, and have the high-voltage fault assessed before continued use.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.