Mercedes-Benz Sprinter Fault Code
Free · no signupP0620
Battery light on; Accessories (AC/Fans) behaving erratically.
System
Charging
Symptom
Battery light on; Accessories (AC/Fans) behaving erratically.
Diagnosis & fix steps
Alternator Control Circuit.
LOGIC: The ECM has lost communication with the "Lin-Bus" alternator.
Red Seal field insights
Sprinter alternators are "smart." If the small wire on the back of the alternator is pinched or corroded, the alternator will default to 13.5V, which isn't enough to charge the AGM batteries used in these vans.
Same code keeps coming back?
That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.
Read before you touch anything
- This is general reference information, not a repair manual. It is for trained, qualified technicians.
- Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
- Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
- You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
- Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.
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