U0160 – Lost Communication With Audible Alert Control Module

System: Network | Standard: ISO/SAE Controlled | Fault type: General

Definition source: SAE J2012/J2012DA (industry standard)

DTC U0160 indicates the vehicle detected a network communication problem involving the Audible Alert Control Module. In practical terms, one or more other modules on the vehicle data network expected to receive messages from (or exchange messages with) the audible alert control module, but those messages were not seen within the required time window. Exact behavior varies by vehicle architecture, including which module sets the code, what messages are considered required, and whether the issue is logged as current or history. Always verify the affected network, module locations, connector views, and pinpoint tests in the correct service information before making repairs.

What Does U0160 Mean?

U0160 – Lost Communication With Audible Alert Control Module means the vehicle’s network diagnostics determined that communication with the audible alert control module was lost. Under SAE J2012 DTC structure, a “U” code is a network-related fault, and this specific entry is defined strictly as a loss of communication with that module—not a direct indication that the module is failed. The code is typically set when expected network messages are missing, invalid, or not acknowledged for a calibrated period, which can be caused by network wiring faults, power/ground issues to the module, connector problems, or the module being offline.

Quick Reference

• Subsystem: Vehicle network communications related to the Audible Alert Control Module.
• Common triggers: Missing periodic network messages, module offline due to power/ground loss, network bus open/short, or poor connector contact.
• Likely root-cause buckets: Wiring/connector faults, network integrity issues, power/ground supply problems, module internal fault, configuration/software issues (varies by vehicle).
• Severity: Usually moderate; audible warnings/alerts may be reduced or unavailable, and other systems may post warnings depending on how alerts are routed.
• First checks: Scan for related U-codes, confirm module presence on the network, inspect fuses and grounds feeding the module, and check connectors for looseness/corrosion.
• Common mistakes: Replacing the module before verifying power/ground and network wiring, or ignoring other network codes that point to the true fault location.

Theory of Operation

The audible alert control module is part of the vehicle’s communication network and is responsible for generating or controlling audible warnings (such as chimes or alert tones) as commanded by other modules. On many platforms, other controllers request audible alerts by sending network messages; the audible alert module may also broadcast its status so the network can confirm it is online and functioning.

U0160 is set when a supervising module determines that required communication with the audible alert control module has stopped. This determination is typically based on message timeouts, missing acknowledgments, or the absence of a module’s expected network activity. The underlying cause may be the module losing power/ground, an open or short in the network wiring, excessive resistance at terminals, or a fault that prevents the module from participating on the bus.

Symptoms

• No chime or reduced audible warnings for conditions that normally trigger alerts.
• Warning indicators or messages related to multiple systems due to shared alert pathways.
• Intermittent operation where audible alerts work sometimes and fail at other times.
• Multiple U-codes stored across modules, especially other network “lost communication” faults.
• Startup alerts missing such as key-in or reminder tones (feature set varies by vehicle).
• Network-related faults appearing after repairs, battery service, or connector disturbance (not proof of cause without testing).

Common Causes

• Open circuit, short-to-power, or short-to-ground on the network communication lines between modules
• High resistance or intermittent connection at the Audible Alert Control Module connector (poor pin fit, corrosion, backed-out terminals)
• Loss of power feed to the Audible Alert Control Module (blown fuse, faulty relay, open in the feed circuit)
• Ground path issue for the Audible Alert Control Module (loose ground fastener, corrosion at ground splice, damaged ground wire)
• Network wiring damage near common flex points (harness chafe, pinch points, prior repair area) causing intermittent bus faults
• Another module on the same network creating bus disruption (dominant bus state, internal fault, or wiring short affecting network integrity)
• Configuration or software-related communication mismatch after service (programming/setup varies by vehicle and may be required)
• Audible Alert Control Module internal fault (consider only after power/ground and network circuits test good)

Diagnosis Steps

Tools typically needed: a scan tool capable of full-network scans and reading module status, a digital multimeter, and access to vehicle-specific wiring diagrams/service information. Helpful extras include back-probing leads, terminal inspection tools, and a way to log live data. Use appropriate battery support if extended key-on testing or module programming is required.

1. Confirm the DTC and capture freeze-frame or event data if available. Run a complete network scan and record all codes in every module, not just U0160, to see whether the issue is isolated to one module or a broader network problem.
2. Check whether the scan tool can communicate directly with the Audible Alert Control Module. If it will not communicate, treat it as a current loss-of-communication condition; if it communicates, treat the concern as intermittent or historical and prioritize harness/connector checks and data logging.
3. Verify the concern is not being created by low system voltage. Check battery state and charging system operation using service information procedures. If multiple modules have communication or undervoltage codes, address power supply stability before deeper network diagnostics.
4. Inspect fuses and relays that feed the Audible Alert Control Module (varies by vehicle). Do not rely on visual inspection alone; confirm power is present on the expected sides of the fuse/relay under the same key position that sets the fault.
5. Perform a targeted visual inspection of the module area and harness routing. Look for unplugged connectors, damaged conduit, chafing, pinched wiring, signs of moisture/corrosion, and evidence of prior repairs. Correct any obvious physical issues found.
6. Check power and ground at the module connector with the connector plugged in where possible. Use voltage-drop testing on the ground path and the power feed(s) under load (key on, and with commanded functions if applicable). Excessive drop indicates resistance in the circuit that can cause module resets and communication loss.
7. With the key off as required by service information, inspect the module connector terminals. Look for spread terminals, backed-out pins, fretting, or corrosion. Perform a light terminal tension check using appropriate tools; repair or replace terminals/connectors as needed.
8. Evaluate the network circuits to the module. Verify continuity end-to-end per wiring diagrams, and check for shorts to ground or power. If the fault is intermittent, perform a wiggle test while monitoring scan tool module status and network DTC counters to see if movement triggers a dropout.
9. Determine whether the network is being disrupted by another module. If multiple “lost communication” codes appear, identify the common network segment and isolate by disconnecting suspected modules one at a time (only as allowed by service procedures) to see whether communication stability returns.
10. After repairs, clear DTCs and perform a verification drive or functional test while logging network/module status. Confirm the Audible Alert Control Module stays online, U0160 does not reset, and no related network codes return.
11. If all power, ground, connector integrity, and network wiring tests pass and the problem persists, follow service information for any required configuration, setup, or software updates. Replace the Audible Alert Control Module only after confirming inputs/feeds and network integrity are correct and stable.

Professional tip: When U0160 is intermittent, prioritize evidence capture over guesswork: log a full-module status list and communication DTC counters during a wiggle test and a road test. A repeating pattern (module resets, multiple modules dropping offline together, or failure only when a harness moves) is often the deciding clue that separates a power/ground issue from a network wiring fault or a disruptive module.

Possible Fixes & Repair Costs

Repair cost for U0160 varies widely because it depends on which part of the network path failed, how accessible the wiring is, and whether the issue is power/ground, a connector problem, or a module-level fault. Diagnose first, then repair only what testing confirms.

• Restore module power and ground: Repair blown fuses, faulty relays, poor grounds, or power feeds that keep the audible alert control module from powering up.
• Repair wiring faults on the network: Fix opens, shorts, chafed sections, or pin-fit issues affecting the communication lines between modules.
• Clean/repair connectors: Address corrosion, moisture intrusion, backed-out terminals, bent pins, or damaged connector locks at the audible alert control module and any in-line junctions.
• Correct high resistance issues: Repair splices or terminals that pass a static check but fail under load; verify with voltage-drop testing on power/ground circuits.
• Re-seat and secure modules and harness routing: Ensure connectors are fully latched and harnesses are not strained, rubbing, or intermittently tugged by movement or vibration.
• Module replacement when proven: Replace the audible alert control module only after verifying correct power/ground and a healthy network at the connector, and after confirming the module will not communicate.
• Configuration/programming as required: Some vehicles require setup, coding, or relearn procedures after module replacement; follow service information.

Can I Still Drive With U0160?

You can sometimes drive with U0160 if the vehicle operates normally and no safety-critical warnings are present, but the loss of communication can disable audible alerts and may coincide with other network-related faults. If you have warning lamps related to braking, steering, stability control, or a no-start/stall condition, or if multiple modules show communication errors, do not drive until the network issue is diagnosed.

What Happens If You Ignore U0160?

Ignoring U0160 can lead to missing audible warnings and intermittent or escalating network issues, including additional communication DTCs, unpredictable feature operation, and repeated battery drain events if a module or network segment fails to sleep properly. An intermittent wiring or connector fault can worsen over time and become a hard no-communication condition.

Last updated: March 15, 2026

Vehicles Commonly Affected by U0160

• Vehicles with a dedicated audible alert control module: Systems where the chime/buzzer functions are handled by a separate controller.
• Vehicles with extensive networked comfort and safety features: More modules increase the likelihood of communication-related DTCs when wiring issues occur.
• Vehicles with recent electrical repairs: Harness routing changes, connector disturbance, or improper pin seating can trigger lost communication.
• Vehicles operated in harsh environments: Corrosion risk at connectors and grounds can contribute to network dropouts.
• Vehicles with prior low-voltage events: Battery or charging issues can expose weak connections and cause modules to reset or drop off the network.
• Vehicles with underbody/impact damage history: Pinched or abraded harness sections can intermittently disrupt the network.
• Vehicles with water intrusion history: Moisture in connectors or junctions can affect communication integrity.
• High-mileage vehicles: Normal aging of terminals, grounds, and harness supports can create intermittent opens.

If U0160 returns after repairs, re-check for intermittent power/ground drops and connector pin-fit issues, and confirm all modules on the network can communicate consistently during a road test and post-test scan.