P0CA4 on Audi: How to Diagnose & Fix
Hybrid / High-Voltage Battery Charging Voltage Too High
1 Audi model · 1 documented issue · 1 critical
P0CA4 on Audi by model: symptoms, diagnosis and fix
Audi TSB 2061788/2 covers model-year 2021 e-tron quattro and e-tron Sportback vehicles with specified AC/DC charging interruptions, charging-flap operation problems, or an app request for auxiliary heating that does not pre-heat the vehicle when matching DTCs are stored in high-voltage battery charger control module J1050. Audi attributes the documented condition to onboard-charger software and identifies old software level 0070, not a proven failed charger module.
Common Symptoms
- AC or DC charging is interrupted
- DC charging does not start or stops at some stations
- Charging-flap button is inoperative or the flap does not open
- Auxiliary heating is activated through the app but the vehicle does not pre-heat
How to Fix
Record whether the failure is AC, DC or station-specific and have J1050 scanned before parts. If the vehicle has the matching condition and software level 0070, Audi directs an SVM update to software 0079 or higher. After the update, reproduce the concern and follow the guided test plan for any new active DTC. Do not infer hardware failure merely because one charging mode works, and do not order the former charger, 12-volt battery, relay, meter or portable EVSE from this card.
Owner tips & cautions
- TipBring the failed station, date and charging mode to the diagnosis and ask for the J1050 software level and full DTC list before authorizing hardware.
Sources for this issue (1)
P0CA4 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0CA4 mean on a Audi?
P0CA4 stands for "Hybrid / High-Voltage Battery Charging Voltage Too High." The onboard charger control module has measured a charging voltage above the permitted limit for the high-voltage battery and aborts or refuses the charging session to protect the pack. Audi TSBs 2061788 and 2062631 list DTC P0CA400 ("Hybrid/high voltage battery load voltage too high") among the codes stored in high-voltage battery charger J1050 on 2020-2021 e-tron quattro and e-tron Sportback that are attributable to old onboard-charger software (level 0070) rather than to failed charging hardware. On Audi it is documented across 1 model: e-tron.
What are the most common causes of P0CA4?
The most common causes of P0CA4 are: Outdated onboard-charger software - Audi documents software 0070 as producing this and other "ghost" DTCs (TSB 2061788 / 2062631), Charging station delivering out-of-spec voltage, Faulty voltage measurement inside the onboard charger, High-voltage battery management or contactor fault. The specific cause varies by vehicle.
How much does it cost to fix P0CA4 on a Audi?
Repair costs vary widely with the root cause and Audi model; each issue on this page carries its own estimate where one is published.
Looking for P0CA4 on a different make?
View P0CA4 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.