Aventon Pace 500/Solon/Aventure.2 — Error Code E04

Reviewed by certified eBike technicians · Last updated July 15, 2026

Quick Answer

E04 on Aventon = Battery communication error — BMS and controller not communicating
Severity: Check soon — battery communication issue · Limited riding OK, diagnose soon

Error E04 on your Aventon indicates: Battery communication error — BMS and controller not communicating.

Check soon — battery communication issue — Battery communication error — BMS and controller not communicating

Symptoms

E04 on Aventon display; battery gauge shows 0% or erratic readings; motor may work intermittently; bike may shut down under load

Common Causes

Battery connector pins dirty or oxidized
Battery not fully seated in the frame mount
Battery BMS firmware needs update
Cell imbalance from prolonged storage at full charge
Damaged communication wire between battery and controller

Fix Steps

Step 1: 1. Remove battery and inspect the gold contact pins on both the battery and frame mount

Step 2: 2. Clean contacts with isopropyl alcohol and a cotton swab

Step 3: 3. Re-seat battery firmly until you hear a positive click

Step 4: 4. Charge battery to 100% and let rest 30 minutes — BMS recalibration

Step 5: 5. If error persists after full charge cycle: battery BMS may need firmware update at Aventon dealer

Step 6: 6. For Aventure.2 models: check the battery latch mechanism — partially engaged latch causes intermittent contact

Step 7: 7. Battery replacement cost: ~$500-650 if out of warranty

Related Error Codes

Error E01

Aventon Pace 500/Solon/Aventure.2 — Error Code E04

Quick Answer

Symptoms

Common Causes

Fix Steps

Related Error Codes

Motor hall sensor fault — controller cannot read motor position

Controller overtemperature — motor controller exceeded 85°C internal limit

Brake sensor engaged — brake cutoff switch stuck or misaligned

Speed sensor signal lost — wheel speed not detected