Comprehensive diagnostic procedure for electric drivability issues on the 2025 Rivian EDV 500 dual motor AWD system, including battery system, motor controllers, drivetrain components, and vehicle communication networks.

Warnings

Tools required

Parts

• 12V Battery × 1 — Use OEM specification
• High-voltage connector seals × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Ensure vehicle is powered off and key fob is at least 15 feet away from vehicle
3. Allow vehicle to sit for at least 5 minutes to allow high-voltage contactors to open
4. Chock rear wheels if testing will require front axle rotation
5. Connect diagnostic scan tool to OBD-II port located under driver's side dashboard
6. Verify scan tool can communicate with all vehicle modules
7. Document all current and pending diagnostic trouble codes before clearing
8. Record customer complaint details including specific conditions when symptoms occur
9. Check for any open recalls or technical service bulletins related to symptoms

Procedure

1. 1

   Verify Customer Complaint and Perform Initial Assessment
   Interview customer or review work order to understand specific drivability concerns (reduced power, jerking, vibration, unusual noises, loss of propulsion, reduced range, regenerative braking issues). Perform visual inspection of vehicle exterior for accident damage, tire condition, and obvious modifications. Check tire pressures and verify all tires are proper size and type. Note any dashboard warning lights or messages displayed.
2. 2

   Test 12V Battery System
   The 12V battery powers all control systems and high-voltage contactor operation. Open hood and locate 12V battery. Test 12V battery voltage with multimeter - should read 12.4-12.8V with vehicle off. Perform load test on 12V battery to verify capacity is above 80%. Check battery terminals for corrosion and ensure tight connections. Test charging system by powering vehicle to READY mode and verifying 12V system voltage rises to 13.5-14.5V. A weak 12V battery can cause intermittent drivability issues, reduced power modes, or complete loss of propulsion.
   ℹ️Unlike conventional vehicles, the 12V battery in EVs is charged by a DC-DC converter from the high-voltage battery, not an alternator.
3. 3

   Retrieve and Analyze Diagnostic Trouble Codes
   Using the diagnostic scan tool, retrieve all DTCs from all vehicle modules including: Battery Management System (BMS), Front Motor Inverter, Rear Motor Inverter, Vehicle Control Module, Gateway Module, and Body Control Module. Document all codes with freeze frame data. Pay special attention to codes related to: motor temperature sensors, resolver position sensors, inverter faults, battery cell voltage deviations, isolation faults, contactor failures, and communication errors. Prioritize addressing any high-voltage safety-related codes first.
4. 4

   Inspect High-Voltage Battery System
   Review battery system data from scan tool including: state of charge, total pack voltage (should be 330-420V depending on charge level), individual cell group voltages (no more than 0.05V deviation between groups), battery temperature (should be 60-85°F in normal operation), charge/discharge current, and isolation resistance (should be above 100 ohms/volt). Check for any battery thermal management system faults. Visually inspect high-voltage battery enclosure underneath vehicle for damage, leaks of coolant, or corrosion at connections. Do not open high-voltage battery enclosure without proper training and safety equipment.
   ⚠️Visual inspection only. Do not attempt to disconnect or open high-voltage battery pack without manufacturer-specific high-voltage safety training.
5. 5

   Test Motor and Inverter Systems
   Review motor and inverter data from scan tool for both front and rear motors: motor temperatures, inverter temperatures, motor RPM, motor torque commands vs actual torque, resolver position sensor signals, three-phase current balance, and inverter DC bus voltage. Use infrared thermometer to check actual motor and inverter housing temperatures and compare to scan tool data - significant differences indicate sensor faults. Check for DTCs related to motor position sensors (resolvers), as these cause jerking, reduced power, or loss of propulsion. Inspect motor high-voltage connectors for damage, corrosion, or loose connections.
6. 6

   Inspect Drivetrain and Differential Fluid
   Lift vehicle on hoist and support safely. Visually inspect front and rear drive units for leaks, damage, or loose mounting bolts. Check differential fluid levels through fill plugs - front differential should have 1.5 quarts 75W-90 GL-5, rear differential should have 2.0 quarts 75W-90 GL-5. Low fluid can cause whining noises, vibration, or driveline shudder. Inspect CV axles and boots for damage or grease leakage. Rotate each wheel by hand and listen for grinding or roughness indicating bearing failure. Check for excessive play in axle shafts.
7. 7

   Test Drive and Data Logging
   If safe to operate, perform test drive with scan tool connected and data logging active. Monitor in real-time: motor torque commands, actual motor torque, motor speeds, battery current, state of charge, accelerator pedal position, brake pedal position, and regenerative braking current. Attempt to replicate customer complaint conditions. Note any specific speed ranges, acceleration rates, or temperatures where symptoms occur. Check for torque reductions commanded by BMS due to temperature limits, cell voltage limits, or isolation faults. Verify both front and rear motors are contributing power equally during acceleration.
8. 8

   Check Cooling System Operation
   Electric motors and inverters require active cooling. Review coolant temperatures from scan tool - motor/inverter coolant should typically run 100-140°F during operation. Verify coolant pump operation by checking pump speed/current data and listening for pump operation. Check coolant level in reservoir (approximately 10 quarts EV Battery/Motor Coolant total capacity). Inspect coolant hoses and connections for leaks. Use thermal camera if available to verify coolant is circulating through motors and inverters. Overheating can cause power reduction or complete shutdown.
   ⚠EV cooling system may contain hot coolant even when vehicle has been off. Allow cooling before opening any coolant system components.
9. 9

   Verify Software Versions and Updates
   Using diagnostic scan tool, check software versions for all control modules including BMS, motor inverters, and vehicle control module. Compare to latest available versions from manufacturer technical information system. Many drivability issues including jerking, power limitations, regenerative braking problems, and range issues are resolved through software updates. Check for any available over-the-air updates or required dealer programming. Document all module software versions before and after any updates.
10. 10

    Inspect Brake System and Regenerative Braking Integration
    Test brake pedal feel and travel. The EDV 500 uses regenerative braking blended with friction brakes. Using scan tool, monitor regenerative braking current during moderate braking - should see negative current (charging) to battery. Check brake fluid level (DOT 4) in reservoir. Inspect brake system for any hydraulic leaks or air in system. Verify ABS module has no faults. Test brake pedal position sensor readings - erratic readings can cause poor regenerative/friction brake blending resulting in jerky stops or reduced regeneration.
11. 11

    Check High-Voltage Contactor Operation
    High-voltage contactors connect battery to motors. Monitor contactor status on scan tool when transitioning vehicle from OFF to READY mode. Should see contactor pre-charge sequence followed by main contactor closure. Check for contactor fault codes. Verify DC bus voltage rises smoothly during pre-charge (should take 1-3 seconds). Listen for contactor clicking sounds from battery area during power-up. Failed or sticking contactors cause no-start, loss of power, or intermittent propulsion loss. Check contactor control circuit voltages if DTCs present.
12. 12

    Verify Torque Vectoring and AWD System Operation
    The dual motor system provides torque vectoring for improved handling. During test drive data logging, verify both motors are operating and responding to commands. Check for individual motor disable flags or faults. Monitor torque distribution between front and rear - should vary based on driving conditions. A failed motor or inverter will result in single-motor operation with reduced performance. Check for yaw rate sensor and steering angle sensor faults that affect torque vectoring logic.
13. 13

    Analyze Communication Network Health
    Electric vehicles rely heavily on CAN bus communication between modules. Using scan tool, check for communication DTCs or module timeout codes. Verify all expected modules are communicating. Check CAN bus voltage on diagnostic connector pins - should see ~2.5V on both CAN High and CAN Low with vehicle powered on. Poor communication can cause limp mode, reduced power, or complete loss of function. Check for water intrusion in connector areas under vehicle that may cause corrosion and communication failures.
14. 14

    Document Findings and Determine Root Cause
    Review all collected data including DTCs, scan tool parameters, test drive observations, and inspection findings. Correlate customer complaint with diagnostic findings. Determine if issue is: electrical (sensors, connectors, modules), mechanical (drivetrain, bearings, mounts), thermal (cooling system), software-related, or 12V system related. Create a prioritized repair plan addressing safety-critical items first. If root cause cannot be determined, consult manufacturer technical support with vehicle VIN, software versions, and detailed symptom description. Document all findings in repair order with specific test results and recommended repairs.

Reassembly

1. Ensure all high-voltage connectors are properly seated and locked if any were inspected
2. Reinstall any inspection covers or panels removed during diagnosis
3. Verify all fluid fill plugs are properly torqued if checked
4. Clear any diagnostic trouble codes that were addressed during diagnosis
5. Lower vehicle from hoist if raised

Verification

• Power vehicle to READY mode and verify no warning lights on dashboard
• Verify all diagnostic trouble codes have been addressed or documented
• Perform final test drive replicating original customer complaint conditions
• Monitor scan tool data during test drive to confirm all systems operating normally
• Verify motor temperatures, battery temperatures, and coolant temperatures are within normal range
• Confirm both front and rear motors are producing commanded torque
• Test regenerative braking operation with smooth deceleration and battery charging
• Verify accelerator response is smooth with no hesitation, jerking, or power loss
• Check that state of charge is stable or increasing during regenerative braking
• Document final test results and provide detailed explanation to customer of findings and any required repairs

More procedures for this vehicle