EV Diagnostic - Common Questions
What EV faults can be diagnosed remotely?
+
Most electric vehicle faults can be analyzed remotely using fault codes, live data, and a structured symptom description. This includes high-voltage interlock (HVIL) faults, BMS errors and state-of-health issues, insulation resistance failures, AC/DC charging faults, thermal management problems, traction inverter faults, 12V system failures, and CAN communication errors. We cover Tesla, Hyundai, Kia, Volkswagen ID series, BMW, Ford, and other EV platforms.
What tools does a shop need to work EV cases?
+
For most EV diagnostic work you need: a professional scan tool with EV/hybrid support (Autel MaxiSys, Launch X431, Snap-on Zeus), a calibrated multimeter rated to 1000V AC/DC, a megohmmeter for insulation resistance testing, and proper HV PPE (Class 0 insulated gloves minimum, face shield, insulated tools). Factory scan tools (Tesla Toolbox, GDS2, ODIS) give deeper data but many faults resolve with aftermarket tools.
How does HVDesk remote support work?
+
Submit a case through the portal with vehicle details, fault codes, symptoms, and previous repair attempts. An EV specialist reviews the case and returns a structured, step-by-step diagnostic procedure within 24 hours. The shop tech executes the tests and can reply with follow-up questions. The procedure includes specific measurements, expected values, and ranked root cause hypotheses. The first case is always free.
What is an HVIL fault and how is it diagnosed?
+
HVIL (High Voltage Interlock Loop) is a safety circuit that monitors the integrity of every HV connector in the vehicle. If any connector is unseated, damaged, or has moisture ingress, the HVIL circuit opens and the HV system is disabled. Common codes: P0AA6, P0AA0, BMS_u029 (Tesla). Diagnosis: measure resistance across each segment of the HVIL loop to isolate the open circuit, then visually inspect and reflow suspect connectors.
How much does EV diagnostic support cost?
+
Pay Per Ticket is $49 per case - no subscription. Shop Pass is $129/month for unlimited cases, best for shops seeing regular EV traffic. Pro Pass is $299/month with priority 12h response and a dedicated specialist. First case is always free for new accounts.
