P0562
PowertrainSystem Voltage Low
The system voltage being supplied to the ECU is below the manufacturer's threshold. The ECU is detecting that the electrical supply isn't adequate to run all systems reliably. This is usually a battery, charging system, or wiring issue rather than an engine fault.
ⓘ Information only. This page provides general educational information about fault code P0562. We do not assess the urgency or safety implications of any specific fault. That requires in-person diagnosis by a qualified mechanic. Full terms.
Recommended next steps
Whether a fault is urgent, drivable, or routine depends entirely on the cause on a specific vehicle, and that can only be determined by a qualified mechanic with diagnostic equipment. If a warning light is illuminated, the most reliable next step is professional diagnosis.
What does P0562 mean?
P0562 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: System Voltage Low.
This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.
Symptoms commonly associated with this code
Symptoms that drivers often report alongside this code. Not all may apply to every case:
- • Engine warning light
- • Possibly multiple unrelated warning lights as various systems struggle with low voltage
- • Hard starting or no-start condition
- • Stalling, particularly when electrical load is high (lights, heater, wipers all on)
- • Erratic gauge behaviour, dashboard displays glitching or rebooting
- • Battery warning light may appear if charging is the issue
Possible causes
Causes commonly associated with P0562, listed in approximate order of typical investigation. The actual cause on a specific vehicle can only be confirmed by professional diagnosis.
- 1. Weak or failing battery (most common cause, particularly on cars over 5 years old)
- 2. Failed alternator not charging properly, voltage at idle should be 13.7-14.7V; below 13.5V suggests an alternator issue
- 3. Worn or loose alternator drive belt slipping under electrical load
- 4. Corroded battery terminals, white or green crusty buildup means the connection is poor
- 5. Damaged main battery cables (positive or earth) reducing supply
- 6. Heavy parasitic drain from aftermarket electrical accessories
- 7. On hybrids: 12V auxiliary battery failing (separate from the main traction battery)
How mechanics typically diagnose
A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training.
- 1. Check battery voltage with a multimeter, healthy is 12.6V or above with engine off, 13.7-14.7V with engine running. Below those values is your prime suspect
- 2. Inspect battery terminals for corrosion, clean with terminal cleaner if there's any green/white buildup
- 3. Check alternator drive belt tension and condition, slipping belts are a common cause
- 4. Test alternator output under load (lights on, heater on, fan on); voltage should hold above 13.5V
- 5. Check earth straps from battery to chassis and engine to chassis for corrosion or damage
- 6. Check for parasitic drain by measuring current draw with the car off, healthy is under 50mA
Common questions about P0562
Just changed the battery and the code is still there +
Possible reasons: the old code stored before the battery change hasn't cleared yet (drive a few cycles), the new battery has a poor terminal connection (clean and reseat), or the underlying cause is the alternator (test voltage with engine running). Some modern cars also need the new battery 'registered' to the ECU via a scan tool, particularly BMW, Mercedes, and newer VAG cars.
Will I get stranded? +
Possibly. P0562 with a hard-starting issue means the battery may not crank the engine reliably, particularly in cold weather. Address it before you're left with a no-start. Carry jumper cables or a jump pack if you must drive while waiting for repair.
Could this be parasitic drain? +
Yes, particularly if the battery seems to be drained when the car has been parked for a few days. Aftermarket alarms, dashcams, audio, or trackers can cause excess drain. Try unplugging recent additions and see if the issue resolves. A multimeter on the battery negative cable measures drain accurately.
Information only, not professional advice
The information on this page is provided for general guidance and educational purposes only. It is not a substitute for diagnosis or repair advice from a qualified mechanic. Always verify any fault before paying for repairs. carfaultcodes.co.uk accepts no liability for decisions made based on this information. Full terms →