U0422 on 2017-2018 Chevrolet Bolt EV: Invalid Data from Body Control Module Explained

What's Unique About the 2017-2018 Chevrolet BOLT EV

For the Chevy Bolt EV, this code is the subject of a specific General Motors Technical Service Bulletin (TSB #16-NA-407). The bulletin explains that U0422 can be set by the Integrated Chassis Control Module (ICCM) during vehicle startup. This happens because arbitration from the PEPS (Passive Entry Passive Start) module combined with high bus traffic can cause the BCM to momentarily set the door open switch signal's availability to 'unavailable'. The BCM won't update this status until the door is physically opened and closed again. GM advises that this specific stored code should be ignored unless it is currently active or accompanied by other specific BCM-related fault codes.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Check Engine Light or other malfunction indicator lamp may be illuminated
• In many cases, there will be no noticeable symptoms at all.

Most Likely Causes

1. Temporary Software Glitch at Startup 🔴 High Probability GM TSB #16-NA-407 directly states this code can be set during vehicle startup due to high bus traffic and PEPS module arbitration causing a momentary loss of the BCM's door switch availability signal. The ICCM sets U0422 if this signal is unavailable for more than one second.
   How to confirm: Check if the code is stored (historical) rather than active. If no other codes (specifically U1534 or U1538) are present and there are no symptoms, this is the likely cause.
   Typical fix: Clear the code. If it does not return and no other codes are present, no further action is needed per GM's official procedure.
   Est. part cost: $0
2. Body Control Module (BCM) Fault ⚪ Low Probability → Shop Body Control Module
   How to confirm: The code will be active or will return immediately after clearing. It will likely be accompanied by other BCM-related codes (like U1534 or U1538) or functional problems with body electronics (lights, locks, windows).
   Typical fix: The BCM may require reprogramming or replacement. This must be done by a qualified technician 🎬 Watch: How a Chevy BCM is replaced and programmed. with access to GM's Service Programming System (SPS).
   Est. part cost: $250-$450
3. Wiring or Connection Issue ⚪ Low Probability
   How to confirm: Visually inspect the wiring harnesses and connectors at both the Body Control Module and the Integrated Chassis Control Module (ICCM) for any signs of damage, corrosion, or loose pins.
   Typical fix: Repair the damaged wiring or clean/reseat the affected connector.
   Est. part cost: $5-$50

Rare But Worth Checking

• Low 12V Auxiliary Battery Voltage: → Shop Vehicle Battery A weak 12V battery can cause unpredictable communication errors between various modules on an EV. Before diving into complex network diagnostics, it's always wise to ensure the 12V battery is healthy and fully charged (at least 12.4-12.6 volts at rest).
🎬 Watch: How to test your EV 12V battery at home.

Diagnosis Steps

1. Use an OBD-II scanner to check if the code is 'Active/Current' or 'Stored/History'.
2. Scan all other vehicle modules for additional codes. Pay close attention to any codes stored in the Body Control Module (BCM), especially U1534 and U1538.
3. Refer to GM Technical Service Bulletin #16-NA-407.
4. If U0422 is the only code present and it is not active, clear the code and monitor to see if it returns. No further action is likely needed.
5. If the code is active or returns, and is accompanied by BCM codes U1534 or U1538, the issue points towards a legitimate BCM or network fault.
6. Test the vehicle's 12V auxiliary battery to ensure it is holding a proper charge (at least 12.6 volts at rest). Low voltage can cause numerous communication faults.
7. Inspect the wiring and connectors for the BCM and Integrated Chassis Control Module (ICCM) for any visible damage or corrosion.
8. If the battery and wiring are confirmed to be good, the problem likely lies within the BCM itself, which may require professional diagnosis with a GM-specific scan tool for reprogramming or replacement.

Parts You'll Likely Need

• Body Control Module (BCM) (OEM #13534187, 13516918, 13543436) — In the rare case that this code indicates a hard fault, the BCM is the source of the invalid data and may need replacement. Part numbers can supersede; confirm with a dealer using the vehicle's VIN.
  Trusted brands: ACDelco (Genuine GM)
  OEM price range: $250-$450
  Aftermarket price range: $150-$300

Related Codes That Often Appear With This One

• U1534 — This is a BCM-related code. TSB #16-NA-407 specifically mentions that U0422 should only be investigated if it is accompanied by this or other BCM faults.
• U1538 — Another BCM fault code. Its presence alongside U0422 indicates a more genuine problem with the BCM or its communications, rather than just a startup glitch.

Technical Service Bulletins (TSBs) & Recalls

• 16-NA-407: Information on Chassis Control Module (CCM) Receives Invalid Data and Sets DTC U0422. This TSB explains the specific conditions under which this code can be set without a true fault and advises technicians to ignore it unless other codes are active.

Platform-Specific Known Issues

• TSB #16-NA-407 was issued by GM specifically to address this code on the 2017-2018 Bolt EV (and other models). It clarifies that the code can be set spuriously on startup due to PEPS module arbitration and high bus traffic causing a temporary loss of the door switch availability signal. It advises to ignore the code unless other specific fault codes (U1534, U1538) are also present.

Mechanic-Grade Diagnostic Values

• CAN Bus Voltage (Recessive/Idle State) — expected: CAN High (Pin 6) and CAN Low (Pin 14) should both be approximately 2.5V.. Failure: Significant deviation from 2.5V on either line when the bus is idle indicates a potential short or open.
• CAN Bus Voltage (Dominant/Transmitting State) — expected: CAN High (Pin 6) rises to ~3.5V and CAN Low (Pin 14) drops to ~1.5V.. Failure: Voltages that do not reach these approximate levels, or are noisy, indicate a communication problem, possibly from a faulty module or wiring.
• CAN Bus Termination Resistance — expected: Approximately 60 Ohms when measured across Pin 6 (CAN High) and Pin 14 (CAN Low) of the OBD-II port with the 12V battery disconnected.. Failure: A reading of ~120 Ohms indicates a missing termination resistor or a break in one of the CAN lines. A reading near 0 Ohms indicates a short between the CAN lines.
• CAN Bus Baud Rate — expected: 500 kbps for the main CAN bus on the Chevrolet Bolt.. Failure: Incorrect configuration in a diagnostic tool will result in no communication.

Hidden / Shadow Codes Worth Checking

• U0422-71: The '-71' is a GM-specific symptom byte meaning 'Invalid Serial Data Received'. This indicates the receiving module has determined the data is invalid, often due to a logic failure, as opposed to a simple loss of communication. GM bulletin PIT5569A clarifies this points to an issue with the data's content, not just its presence, and advises diagnosing the source module's inputs first. (see via A professional scan tool like the GM GDS2 (Global Diagnostic System 2) is required to read these two-digit symptom bytes.)

Scan Tool Commands That Help

• GM GDS2: Vehicle DTC Information — This is the initial full-system scan to see which modules are reporting U0422 and, more importantly, to check for any other codes (like U1534/U1538 in the BCM) or modules that are not communicating at all.
• GM GDS2: Module Diagnostics > BCM > Data Display — To view the live data stream from the Body Control Module. This allows a technician to observe the data being sent to other modules in real-time to check for irrational values, which is the root cause of a U0422 code.
• GM GDS2: Module Diagnostics > BCM > Control Functions — To perform bidirectional tests, such as commanding lights, locks, or windows to operate. If the BCM can successfully command these functions, it suggests the module's core hardware is likely okay, pointing the diagnosis more toward a software or communication bus issue.

Wiring & Ground Locations

• K9 Body Control Module (BCM) — Located on the floor, under the dashboard, near the passenger side of the center console. The carpeting must be pulled back to access it.. This is the module sending the invalid data. Physical inspection for water intrusion, corrosion, or loose connectors is a key diagnostic step for a persistent U0422 fault.
• K17 Chassis Control Module (ICCM) — The specific location for the Bolt EV's Chassis Control Module (also called Integrated Chassis Control Module) is not clearly detailed in the search results, but it is the module that *sets* the U0422 code upon receiving bad data from the BCM.. This module is the 'receiver' of the bad data. While less likely to be the cause, its connector and wiring should be inspected if BCM-side checks reveal no issues.
• OBD-II Port CAN Pins — The standard OBD-II diagnostic port under the driver's side dashboard.. Pin 6 is CAN High and Pin 14 is CAN Low. A technician will use these pins with a breakout box and oscilloscope or multimeter to measure bus voltage and resistance to diagnose the health of the entire network.
• Cabin Ground Stud — There is a ground stud on the body located below the instrument panel fuse box, near the floor in the driver's footwell area.. A poor ground connection for the BCM or other modules can cause unstable voltage and lead to corrupted data transmission, triggering U-codes. Ensuring this ground is clean and tight is a fundamental step in diagnosing any network code.

OEM Part Supersession History

• 13534187 → 13543436 — Part number evolution and consolidation by the manufacturer.
  Heads up: While these part numbers may supersede, programming is always required. A BCM must be programmed with the vehicle's specific VIN and configuration using GM's Service Programming System (SPS) to function correctly.

Model Year Variations Within This Range

• 2017-2018: The primary differences between 2017 and 2018 Bolt EVs were minor feature and color options, such as the introduction of an automatic heated steering wheel and new paint colors in 2018. There is no evidence from the search results to suggest any changes to the BCM, ICCM, or related network architecture that would affect the diagnosis of U0422 within this year range.