U0107 – Lost Communication With Throttle Actuator Control Module

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

Definition source: SAE J2012/J2012DA (industry standard)

U0107 indicates that one or more control modules on the vehicle network have detected a loss of communication with the Throttle Actuator Control Module. In practical terms, the modules expected to exchange messages over the network but could not receive valid data from that throttle actuator control module within the required time. Because network design, module naming, and monitoring logic vary by vehicle, the exact conditions that set U0107 (and the resulting operating strategy) can differ. Always confirm which module is reporting the code, whether U0107 is current or history, and what other network or power-related DTCs are present using the correct service information for the vehicle.

What Does U0107 Mean?

U0107 – Lost Communication With Throttle Actuator Control Module means the vehicle’s networked control system has identified a communication loss involving the Throttle Actuator Control Module. Under SAE J2012 DTC conventions, a “U” code points to a network communication concern, and this specific entry is defined strictly as a loss of message exchange with that module. The code does not, by itself, prove the throttle actuator, throttle body, or a specific wire is failed; it only indicates that expected network messages from the Throttle Actuator Control Module were not successfully received or validated during the monitor’s decision window.

Quick Reference

• Subsystem: Vehicle communication network (module-to-module messaging) involving the Throttle Actuator Control Module.
• Common triggers: Module offline, network bus interruption, missing power/ground to the throttle actuator control module, or high resistance/intermittent connections causing message loss.
• Likely root-cause buckets: Wiring/connector issues on the network; power/ground supply problems; module internal fault; network topology issues (varies by vehicle); software/configuration concerns where applicable.
• Severity: Often moderate to high; may cause reduced engine power, poor throttle response, or a no-start/stall depending on strategy.
• First checks: Scan for related U-codes and power-supply DTCs, verify module power/grounds, inspect network connectors for damage/corrosion, and confirm the code is current.
• Common mistakes: Replacing throttle/actuator parts without confirming network communication, overlooking shared power/ground faults, and ignoring companion network or voltage-related codes.

Theory of Operation

The Throttle Actuator Control Module (implementation varies by vehicle) participates on the vehicle network and exchanges data such as actuator status, commanded position, and diagnostic state with other controllers. The network uses periodic messages and acknowledgments (protocol varies by vehicle). Other modules continuously monitor whether expected messages arrive on time and whether message content is valid.

U0107 is set when the monitoring module determines that communication with the Throttle Actuator Control Module has been lost, typically after a defined number of missed messages or failed validations. Causes can include the throttle actuator control module losing power or ground, a network bus open/short/high resistance, poor terminal fit, or an internal module fault. Many vehicles will enter a protective strategy to limit throttle authority when the module’s data cannot be trusted.

Symptoms

• Warning light: Malfunction indicator or other warning indicators illuminated (varies by vehicle).
• Reduced power: Limited throttle response or reduced engine power mode.
• Poor throttle control: Hesitation, delayed response, or inconsistent acceleration.
• No-start: Engine may crank but not start on some platforms depending on control strategy.
• Stall: Engine may stall, especially during transitions like idle-to-acceleration.
• Multiple codes: Additional network communication codes or low-voltage/power supply related DTCs may be present.
• Intermittent behavior: Symptoms may come and go with vibration, temperature change, or harness movement.

Common Causes

• Open, shorted, chafed, or high-resistance wiring in the network communication circuits between the throttle actuator control module and the rest of the network
• Loose connectors, poor terminal tension, pushed-out pins, corrosion, or moisture intrusion at the throttle actuator control module connector or network junction points
• Loss of module power supply (blown fuse, faulty relay, open feed, excessive voltage drop on the power circuit)
• Loss of module ground (open ground, high resistance at ground point, ground fastener/eyelet issues, excessive voltage drop on the ground return)
• Network faults elsewhere that disrupt communication (short-to-power/short-to-ground on the bus, damaged backbone wiring, failed splice/junction, incorrect termination or termination issue where applicable)
• Throttle actuator control module internal fault (hardware failure) preventing it from communicating on the network
• Software/configuration issue affecting module communication (programming mismatch or corrupted software, where applicable by vehicle design)
• Low system voltage or unstable electrical supply causing modules to drop offline intermittently (battery/charging system concerns, poor main connections)

Diagnosis Steps

Tools typically needed include a capable scan tool with network functions (module list, DTC details, live data, and logging), a digital multimeter, and access to wiring diagrams and connector views for the vehicle. Depending on design, a breakout lead set and test light may help for basic feed checks. Use service information for connector pinouts, fuse/relay identification, and network topology (varies by vehicle).

1. Confirm the complaint and capture data: Retrieve all stored and pending DTCs from all modules, not just one. Save freeze-frame/environment data and record which modules report U0107 or other network-related codes.
2. Check module presence on the network: Use the scan tool’s module list/network test to see whether the throttle actuator control module is detected. Note if communication is completely absent or intermittent.
3. Assess severity indicators: Observe the instrument cluster and scan data for reduced power mode, electronic throttle warnings, or other related indicators. If the vehicle exhibits stalling/no-start or severe throttle limitation, pause diagnosis for safe-work planning and avoid road testing.
4. Clear and recheck: Clear DTCs and cycle the ignition as directed by service information. Re-scan to see if U0107 resets immediately (hard fault) or only after a drive/heat/vibration event (intermittent).
5. Perform a careful visual inspection: With the ignition off, inspect the throttle actuator control module area (varies by vehicle) and harness routing. Look for rub-through, pinched sections, prior repairs, and signs of water intrusion. Verify connectors are fully seated and locked.
6. Wiggle test with live monitoring: While monitoring module presence and relevant network PIDs on the scan tool (and logging if available), gently wiggle the harness and connectors at the throttle actuator control module, nearby splices, and known flex points. If communication drops in/out, focus on that segment and connector terminals.
7. Verify powers and grounds under load: Using wiring diagrams, backprobe the module’s power feeds and grounds. Check for voltage drop on the power circuit and on the ground return while the circuit is loaded (key on, and as applicable during commanded wake-up). Repair any high-resistance feeds, grounds, or poor connections found.
8. Check fuses/relays correctly: Confirm any module-related fuses are intact and that power is present on both sides when expected. Verify relay function where applicable. Do not rely on visual fuse inspection alone; verify with meter tests.
9. Inspect and test the network circuits: With the system powered down as required by service information, inspect network wiring at the module connector for damaged terminals and verify continuity and isolation between the network conductors and to power/ground. If service information calls for it, check for abnormal resistance conditions in the network path that would indicate opens/shorts or termination issues (procedure varies by vehicle).
10. Isolate the fault if needed: If the network is disrupted, isolate segments using approved disconnect points (junctions/connectors) per service information to determine whether the issue is in the module branch, the backbone, or another node pulling the network down.
11. Evaluate the module only after circuit checks pass: If the throttle actuator control module has correct power/ground, network circuits test good, and other modules communicate normally, suspect an internal module fault or a software/configuration issue. Follow service information for any required setup, programming, or relearn steps before/after replacement.
12. Verify the repair: After repairs, clear DTCs, run the network/module scan again, and perform a road test or functional test as allowed. Confirm U0107 does not return and that throttle-related warnings and drivability concerns are resolved.

Professional tip: Treat U0107 as a communication problem first: verify module power/ground integrity and the network path before condemning throttle components. Use scan-tool logging during a wiggle test to catch brief dropouts, and prioritize voltage-drop findings on feeds/grounds because a module can appear “dead on the network” even when fuses look good.

Possible Fixes & Repair Costs

Repair cost and time can vary widely because U0107 is a network communication fault and the underlying cause could be as simple as a connection issue or as involved as circuit repair or module replacement. Final scope depends on confirmed diagnosis, parts required, and labor access.

• Clean, reseat, and secure connectors related to the throttle actuator control module and the communication network; repair poor pin fit, corrosion, or water intrusion only if verified.
• Repair or replace damaged wiring in the network communication circuits (including shorts, opens, or high resistance) found during continuity and voltage-drop testing.
• Restore proper power and ground to the throttle actuator control module by repairing feeds, grounds, fuses, or splice points shown to be faulty under load.
• Correct network integrity issues by repairing affected harness sections, connectors, or splice packs where multiple modules share the communication bus.
• Perform a module reset/relearn procedure if required by service information after power repairs or connector work (procedure varies by vehicle).
• Reprogram or replace the throttle actuator control module only after all network, power, and ground checks pass and the module is confirmed not communicating.

Can I Still Drive With U0107?

Driving with U0107 is not recommended unless the vehicle is operating normally and no warning indicators or drivability changes are present. Loss of communication with the throttle actuator control module can lead to reduced power, limited throttle response, unstable idle, stalling, or a no-start condition depending on vehicle strategy. If you experience stalling, severe reduced power, inability to control speed, or any safety-related warning messages, do not continue driving; arrange for diagnosis and repair.

What Happens If You Ignore U0107?

Ignoring U0107 can result in intermittent or worsening communication loss, which may cause unpredictable throttle response, repeated reduced-power operation, stalling, or failure to start. Continued operation can also complicate diagnosis as additional network-related codes may set when modules drop off the bus due to the same underlying wiring, connector, or power/ground fault.

Last updated: March 14, 2026

Vehicles Commonly Affected by U0107

• Vehicles using electronic throttle control where a dedicated throttle actuator control module communicates over the vehicle network
• Platforms with high network traffic and multiple control modules sharing a common communication bus
• Vehicles with engine compartments prone to harness movement near the throttle body area
• Applications with long harness runs between the throttle actuator control module and main network junctions
• Vehicles with prior wiring repairs, accessory installations, or harness modifications affecting shared network circuits
• Vehicles exposed to moisture, heat cycling, or vibration that can degrade connectors and splice points over time
• Vehicles where the throttle actuator control module is mounted in a location with higher exposure to contaminants
• Vehicles with intermittent battery, charging, or ground-quality issues that can disrupt module communication

For best results, confirm the repair by running a complete drive cycle or functional check specified in service information and ensuring the throttle actuator control module remains online with stable communication during live-data monitoring.