Some battery types can give off gases while charging; for that case the conductive charging standards provide a state in which the vehicle asks the station for ventilation. The vehicle signals it by switching a much smaller resistor of about 270 Ω onto the pilot, which drags the level to around 3 V; the station then only delivers power where ventilation is assured. P0D00 reports that the control circuit of this ventilation switch is open. No manufacturer documents this code publicly; GM's Chevrolet Volt monitors the switch for plausibility only (P0D01, normalized pilot voltage 0.04-0.10 in a self-test), and CARB requires plug-in vehicles to monitor the charging system. During normal charging the switch stays open, so an open circuit often goes unnoticed except for the stored code. Shorts are P0D02/P0D03.
Medium severity. Can I keep driving?If the battery warning light comes on, you could get stranded. Turn off electrical accessories and go straight to a repair shop.
Symptoms
- Stored code, charging usually still works
- Charging system warning in the cluster
Most likely causes
- Open control wire or loose connector of the ventilation switch circuit
- Ventilation switch or its resistor branch open inside the module
- Failed driver stage in the charging control module
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
What each character of P0D00 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- D: Subsystem depends on the code range
- 00: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0D00?
If the battery warning light comes on, you could get stranded. Turn off electrical accessories and go straight to a repair shop.
What causes code P0D00?
The most common causes are: open control wire or loose connector of the ventilation switch circuit; ventilation switch or its resistor branch open inside the module; failed driver stage in the charging control module.
Related codes
- P0D01Control Pilot Charging Ventilation Switch Range/Performance
- P0D02Control Pilot Charging Ventilation Switch Circuit Low
- P0D03Control Pilot Charging Ventilation Switch Circuit High
- P0D04Control Pilot Charging Ventilation Switch Intermittent/Erratic
- P0D05Control Pilot Charging Ventilation Switch Stuck Off
- P0D06Control Pilot Charging Ventilation Switch Stuck On
Sources
- law.cornell.edu: 13 CCR 1968.2
- en.wikipedia.org: SAE J1772
- gsi.ext.gm.com: 19OBDG01 Hybrid Diagnostics
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.