What this code means
U0155 may mean the acoustic vehicle alerting control unit is not receiving expected communication from the gauge control module.
What the vehicle may do
- The vehicle may show warning indicators or communication-related symptoms.
- The acoustic vehicle alerting system may not behave normally.
- Symptoms can vary depending on whether the gauge control module wakes up and communicates.
Possible fault areas
- Possible gauge control module start-up concern.
- Possible gauge control module power or ground circuit concern.
- Possible communication network concern between the acoustic vehicle alerting control unit and the gauge control module.
Diagnostic path
Opening context
On this Accord Hybrid, U0155 is a lost-communication code between the acoustic vehicle alerting control unit and the gauge control module. In plain terms, the alerting control unit may not be getting the gauge data it expects. The vehicle may have warning indicators, communication-related symptoms, or acoustic alerting behavior that is not normal. Broadly, the fault area can involve module wake-up, power and ground to the gauge control module, or the communication network path between the modules.
Pre-checks before chasing the network
Before you go deep into the communication side, handle the basics in order. If other codes are present, check what they mean first and follow the appropriate B-CAN diagnostic direction. Also keep in mind that this code may set if the gauge control module does not start normally, and it may also set from a gauge control module power or ground circuit problem. So before troubleshooting U0155 itself, check the gauge control module power and ground circuits first.
Confirmation setup
To run the confirmation portion, turn the vehicle to the ON mode.
Monitor gate
Once the vehicle is in ON mode, wait for at least 6 seconds. That wait gives the communication monitor time to run under the required condition.
Testing logic
The diagnostic logic is simple: the acoustic vehicle alerting control unit expects specified data from the gauge control module. If that data is not received, it determines there is an abnormality and stores U0155. So the path starts with module start-up and gauge power and ground, then moves into the communication diagnosis if those basics check out.
Verification and takeaway
Keep verification separate from the testing steps. After the basic checks and any network diagnosis are complete, verify the repair and confirm the code stays gone. The takeaway: for U0155, do not jump straight to a module. Make sure the gauge control module wakes up, has good power and ground, and can communicate as expected. For more diagnostic training, visit stepdiagnostics.com.
Final check
U0155 is best approached by checking module start-up, power and ground, and communication logic before making any parts decision.
For more guided automotive diagnostics, visit STEP Diagnostics.
