Comprehensive electrical system diagnosis procedure for the 2024 Rivian EDV 500 dual motor electric delivery van, including high-voltage and low-voltage system troubleshooting.

Warnings

Tools required

Parts

• 12V auxiliary battery (if defective) × 1 — Use OEM specification
• High-voltage connector seals (if damaged) × 1 — Use OEM specification
• Fuses (various ratings as needed) × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Ensure vehicle is in PARK mode and powered OFF
3. Chock rear wheels for safety
4. Put on appropriate PPE including insulated gloves rated for high-voltage work if HV diagnosis is required
5. Access Rivian service information system and retrieve any stored diagnostic trouble codes (DTCs)
6. Document customer complaint with specific symptoms, frequency, and environmental conditions
7. Verify 12V auxiliary battery voltage is above 12.4V before beginning diagnosis
8. Ensure diagnostic equipment is properly calibrated and functioning
9. Review vehicle wiring diagrams and component locations for the affected system

Procedure

1. 1

   Initial System Scan and Code Retrieval
   Connect the diagnostic scanner to the OBD-II port located beneath the driver side dashboard. Power on the vehicle to accessory mode by pressing brake and pushing power button once without holding. Establish communication with all vehicle modules and perform a comprehensive system scan. Record all diagnostic trouble codes (DTCs) from all modules including battery management system, motor inverters, body control module, gateway module, and auxiliary systems. Note any pending, current, or history codes. Document freeze frame data associated with each code.
2. 2

   Verify 12V Auxiliary Battery System
   Using the CAT III rated multimeter, measure 12V auxiliary battery voltage at the battery terminals located in the front compartment. Voltage should read 12.4-12.8V with vehicle off, and 13.8-14.4V with vehicle in accessory or ready mode. Perform a load test if voltage is marginal. Check all 12V battery connections for corrosion, looseness, or damage. The auxiliary battery powers all low-voltage systems and communication networks; a weak battery can cause multiple seemingly unrelated electrical faults.
3. 3

   Inspect High-Voltage Service Disconnect Status
   Verify the high-voltage service disconnect plug is fully seated and locked in position. This is located in the left rear compartment behind an access panel. Look for the green indicator light or position marker confirming proper connection. Check for any signs of arcing, melting, discoloration, or damage to the disconnect housing. Verify the interlock circuit continuity through the diagnostic scanner. A faulty service disconnect or interlock will prevent high-voltage system operation and set DTCs.
4. 4

   Analyze CAN Bus Communication Networks
   Using the diagnostic scanner, verify communication on all CAN bus networks: high-speed CAN, medium-speed CAN, and low-speed CAN. Check for U-codes (network communication codes) that indicate module communication failures. Measure CAN bus termination resistance between CAN-High and CAN-Low pins at the OBD-II port; should read approximately 60 ohms with vehicle off (two 120-ohm terminators in parallel). If communication faults exist, use wiring diagrams to identify the affected network segment and trace for shorts, opens, or damaged wiring.
5. 5

   Test High-Voltage Battery Pack Isolation
   Using the diagnostic scanner, access the battery management system (BMS) live data and check the high-voltage isolation resistance values. The BMS continuously monitors isolation between the high-voltage battery pack and vehicle chassis. Isolation resistance should typically be above 500 ohms per volt (minimum 200 kΩ for a 400V system). Low isolation resistance indicates a potential high-voltage current leak to ground, which is a serious safety concern and will prevent vehicle operation.
6. 6

   Inspect High-Voltage Wiring and Connectors
   Perform a thorough visual inspection of all high-voltage cables (identified by orange coloring). Check for physical damage, chafing, cuts, heat damage, or exposure of conductors. Inspect all high-voltage connectors for proper seating, locking tabs engaged, and seal integrity. Look for signs of moisture intrusion, corrosion, or arcing at connector interfaces. Pay special attention to areas where cables pass through bulkheads or near moving components. Any damage to high-voltage components requires immediate attention.
7. 7

   Check Motor Inverter Operation and Faults
   Access motor inverter diagnostic data for both front and rear drive units through the scanner. Review inverter temperature readings, gate driver status, IGBT health parameters, and any inverter-specific fault codes. Check for phase current balance issues, temperature anomalies, or gate driver faults. Review resolver or encoder signals for motor position feedback. Motor inverter faults can cause reduced power, limp mode operation, or complete loss of propulsion.
8. 8

   Test Electric Motor Winding Resistance
   If motor faults are suspected and safe to access, verify high-voltage system is de-energized and locked out. Disconnect the motor phase cables at the inverter. Using a high-range ohmmeter, measure resistance between each motor phase winding (U-V, V-W, W-U). All three measurements should be equal within 5% (typically 0.1-0.5 ohms depending on motor design). Measure insulation resistance from each phase to motor housing; should be greater than 10 megohms. Unbalanced phase resistance indicates winding damage.
9. 9

   Verify DC-DC Converter Operation
   The DC-DC converter steps down high-voltage battery power to charge the 12V auxiliary battery and power low-voltage systems. With vehicle in ready mode, measure 12V system voltage at multiple points including the auxiliary battery, fuse box, and various loads. Voltage should be stable at 13.8-14.4V. Check for ripple voltage using oscilloscope; excessive AC ripple on DC output indicates converter issues. Access DC-DC converter data through scanner to check input voltage, output voltage, output current, and temperature.
10. 10

    Diagnose Specific Circuit or Component Fault
    Based on DTCs and symptoms, isolate the specific circuit or component causing the concern. Use wiring diagrams to identify circuit paths, connector locations, and component grounds. Perform voltage drop testing on suspect circuits with load applied. Check for proper power supply, ground integrity, and signal quality at the affected component. Use backprobing techniques or connector breakout boxes to avoid damaging connectors. Compare live data readings to expected values from service information.
11. 11

    Inspect Fuses and Relay Connections
    Check all relevant fuses in both the main fuse box (front compartment) and auxiliary fuse panels. Use the vehicle fuse diagram to identify circuits related to the fault. Inspect fuse terminals for corrosion or looseness. Check relays for proper seating and test relay operation by swapping with an identical relay if available. Listen for relay click when circuit is activated. Use multimeter to verify relay coil resistance and contact continuity when energized.
12. 12

    Perform Pinpoint Tests per DTC
    Follow Rivian factory diagnostic procedures for the specific DTCs retrieved. Perform all pinpoint tests as outlined in service information, including resistance checks, voltage tests, and component activations using the scan tool. Document all test results. If service information is not available, use logical diagnostic flow: verify power and ground to component, check signal circuits for shorts or opens, verify component operation with direct tests, and confirm control module output commands are correct.
13. 13

    Clear Codes and Road Test Verification
    After identifying and addressing the root cause, clear all diagnostic trouble codes using the scan tool. Perform any required relearn or initialization procedures for replaced components. Conduct a comprehensive road test under conditions that replicate the original customer concern. Monitor live data during the test to verify proper system operation. Accelerate, decelerate, turn, and drive at various speeds to exercise all electrical systems. Return and perform a final system scan to verify no codes have returned.

Reassembly

1. Reinstall any access panels, covers, or trim pieces removed during diagnosis
2. Ensure all high-voltage connectors are properly seated with locking tabs engaged if any were disturbed
3. Verify high-voltage service disconnect is fully installed and locked
4. Reconnect 12V auxiliary battery if it was disconnected
5. Restore any protective covers over high-voltage components
6. Clean work area and remove any tools from vehicle compartments

Verification

• Perform final comprehensive scan of all vehicle modules to confirm no diagnostic trouble codes are present
• Verify all electrical systems function normally including propulsion, charging, lighting, HVAC, and accessories
• Check that battery state of charge, voltage, and isolation values are within normal range
• Confirm 12V auxiliary battery voltage remains stable at 13.8-14.4V with vehicle in ready mode
• Test drive vehicle and verify customer concern has been resolved under same conditions that caused original fault
• Document all diagnostic findings, tests performed, and repairs made in vehicle service history
• Provide customer with explanation of fault cause and any recommended preventive maintenance

More procedures for this vehicle