← I-Pace
Autopapyrus · Jaguar I-Pace (1st generation)
https://autopapyrus.com/guides/jaguar/i-pace/high-voltage-battery-diagnostics/
Compiled automatically from service literature and owner experience. Specs are for the typical configuration — check them against your exact car before you start.

Jaguar I-Pace (1st generation): High-Voltage Battery Diagnostics

The I-Pace traction battery is a liquid-cooled lithium-ion pack of about 90 kWh (nominal ~90 kWh, usable capacity about 84.7 kWh) at roughly 390 V. The check covers reading BECM data, assessing cell condition, inspecting the pack housing and checking service campaigns. On 2019-2020 models there were battery recall campaigns (cell overheating, fire risk, BECM software update, and in some cases battery replacement).

Difficulty: Hard Time: 1-2 hours (owner inspection without opening the battery); full diagnostics at a repair shop take 2 hours or more Steps: 11

Parts

5
№Part
01 High-voltage battery pack assemblyif faulty
02 12 V auxiliary batteryif faulty; sold separately from the high-voltage battery
03 Battery contactorsif faulty
04 Battery energy control module (BECM)if faulty
05 Battery circuit coolantif faulty

Tools

7
  • Diagnostic scanner with Jaguar support (JLR SDD/Pathfinder or a compatible OBD-II tool)
  • CAT III 1000 V multimeter
  • Class 0 (1000 V) gloves
  • dielectric mat
  • thermal imager (recommended)
  • flashlight
  • vehicle lift

Step by step

11 steps
  1. First, check with an authorized Jaguar dealer whether all recall campaigns for your VIN have been completed. If a battery campaign is still open, do not charge the vehicle to 100% before servicing. Do not leave it charging unattended in a garage, and park it outdoors whenever possible.
  2. Do a visual inspection without opening anything. Raise the vehicle on a lift and inspect the underbody and battery housing for impact dents, cracks, signs of coolant leaks, corrosion and damaged protective plates. Any housing deformation is a reason to stop driving the vehicle and contact a repair shop.
  3. Inspect the orange high-voltage cables and connectors around the battery, inverter and onboard charger for melting, chafing and loose retainers. Do not touch them without disconnecting the HV system.
  4. Connect the scanner and read the fault codes from all modules, especially the BECM (battery energy control module), BCCM (charging) and the drive modules. Record any codes related to insulation (insulation/isolation fault), contactors, cell temperature and voltage imbalance.
  5. In the BECM live data, evaluate the following: total pack voltage, individual cell/module voltages (at rest, the spread between the highest and lowest cell should normally be small, tens of millivolts; a spread above 100 mV indicates a problem), module temperatures (spread of no more than a few degrees), state of charge (SoC) and state of health (SoH, remaining capacity).
  6. To assess capacity, perform a control cycle: charge to 100%, then drive or discharge on a flat route while recording the energy used. Alternatively, use the capacity test function in the diagnostic software. Compare the result with the nominal figure of about 90 kWh. A drop of more than 10-15% at low mileage is grounds for a warranty claim (the HV battery has an 8-year/160,000 km warranty).
  7. Check the battery cooling system: the level and condition of the battery circuit coolant (per the service schedule), pump and fan operation, and the absence of air locks. Battery overheating during charging is a common sign of a cooling circuit fault.
  8. If you need an electrical check (insulation measurement, HV bus voltage), do it only with the high-voltage system disconnected. Procedure: switch the vehicle off, take the key/remove the fob a safe distance from the cabin, disconnect the 12 V battery, and wait at least 10 minutes for the capacitors to discharge (exact time and procedure per the Jaguar service manual). Then disconnect the HV service disconnect, put on 1000 V gloves, and confirm there is no voltage on the HV bus with a CAT III 1000 V multimeter. Only then begin work.
  9. Measure the insulation resistance of the HV circuits relative to the body ground with an insulation tester rated for HV systems (criterion per the manufacturer's specification; as a rule, no less than several hundred ohms per volt of operating voltage). Low insulation resistance requires tracing the leak section by section.
  10. Check the 12 V auxiliary battery: resting voltage should be about 12.4-12.8 V. On the I-Pace, a weak 12 V battery is a common cause of false high-voltage system faults, failures to start (READY) and drive system fault warnings.
  11. Based on the results, draw a conclusion: the battery is healthy, the BECM software needs an update, modules/contactors need replacing, or the complete battery needs replacing. Opening and repairing the HV battery must be done only at a specialized repair shop.

Common mistakes and warnings

  • Working on the high-voltage system (about 390 V) is dangerous to life and health
  • Without training, 1000 V gloves and knowledge of the HV disconnection procedure, do not go beyond visual inspection and reading data with a scanner
  • If you notice smoke, an electrolyte smell, hissing, overheating or battery fault warnings, stop the vehicle immediately at a safe distance from buildings and people, do not charge it, and call a tow truck to take it to a Jaguar service center
  • The exact cell voltage thresholds, insulation resistance limits and HV disconnection procedure for your software version are not fully documented in public sources, so follow the manufacturer's service manual