U0193

Code

Generic U — Network/User

Lost Communication With Digital Audio Control Module A

Brand: Generic

Type: U — Network/User

Views: UK: 30 EN: 54 RU: 29

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Page language: EN

Connect a factory-level or capable scan tool, read U0193 and freeze frame/occurrence data
Check list of modules the scan tool can see — is the audio module present or absent?
Inspect relevant fuses and relays for the audio module and accessory power circuits
Visually inspect module connectors and harness for corrosion, bent pins, water intrusion, or damage
Measure supply voltage and ground at the audio module power pins with key on and key off as required
Check for CAN/LIN/MOST data activity at the module connector with a scope or breakout tool

Battery/ignition supply to module: approx. 11–14.5 V (key ON/engine RUN)
Module ground: near 0 V; continuity to chassis ground
CAN_H idle: ~2.5 V; CAN_L idle: ~2.5 V (recessive state)
CAN dominant state: CAN_H ~3.5 V, CAN_L ~1.5 V (when active)
Differential idle voltage: ~0 V with matching ~2.5 V rails
Bus termination resistance (CAN): ~60 Ω measured across CAN_H and CAN_L with key OFF

Verify the code and occurrence conditions with a scan tool; record freeze frame and related U-codes
Confirm whether the audio module appears on the vehicle network via the scan tool node list or network map
Check for obvious issues: blown fuses, disconnected connectors, water damage, or damaged wiring near the module
With vehicle OFF, perform an ohm check of power and ground pins at the module connector to chassis ground and battery positive
With ignition ON, backprobe the audio module data pins and measure CAN_H/CAN_L (or LIN/MOST) voltages for correct idle values and for traffic using a scope or CAN bus monitor
If no bus activity at the module but present at gateway, check continuity of data pair from gateway to module and inspect connectors; repair wiring as required
If the entire bus is inactive or shows abnormal voltages, isolate sections of the bus to find the shorted node (unplug suspected modules one at a time and observe bus behavior)
Inspect and measure termination resistors; replace or repair missing/incorrect termination
If wiring and power/ground are good and the bus is healthy but the module still doesn’t respond, try reflashing/reprogramming to correct software mismatch if applicable
If reprogramming not possible or fails and wiring is verified good, consider replacing the audio control module and retest
Clear codes, road test, and verify the module communicates reliably and that the original symptom is resolved

No battery power or missing ground at the audio module connector
Open or shorted CAN/LIN/MOST data pair to the module
Corroded connector pins at the module or body harness
Faulty audio module internal electronics
Bus off condition caused by a shorted node or missing termination resistor
After-market device or improper module programming interfering with bus communication