U0194
Lost Communication With Digital Audio Control Module B
Causes
- Faulty or disconnected DACM (Digital Audio Control Module B)
- Open, shorted or high-resistance wiring on CAN/LIN communication circuits
- Poor power or ground supply to the DACM
- Blown fuse or relay supplying the module
- Corroded/damaged connectors or pins
- Fault in another network module (BCM, gateway, audio head unit) affecting bus traffic
Symptoms
- No audio or intermittent audio from affected zones
- Audio-related features (phone, navigation, presets) unavailable or showing errors
- Infotainment or radio display may show module missing or communication fault
- One or more related modules report U0194 or other network U-codes
- Possible warning message or chime related to audio or network
What to check
- Read all U-codes and freeze frame with a dealer-level scan tool; note related network codes
- Check battery voltage (should be stable ~12–14 V) and clear low-voltage conditions
- Inspect fuses and relays that feed the DACM and associated network modules
- Visually inspect DACM connector and wiring for corrosion, damage, or loose pins
- Check for physical damage or water intrusion in dash/console areas
- Verify presence of the DACM on the bus with a scan tool (module list)
Signal parameters
- CAN High and CAN Low idle voltage: approximately 2.5 V each; differential ~0 V
- CAN dominant state: CANH ≈ 3.5 V, CANL ≈ 1.5 V (differential ≈ 2.0 V) during activity
- Typical CAN bus data rates: 500 kbps (high speed) or 250 kbps (mid speed) depending on vehicle
- Bus termination: approx. 60 ohms measured across CANH–CANL at key harness connector
- Module supply voltage: battery voltage (approx. 12–14 V) at DACM power pin
- Module ground: continuity to chassis ground with low ohms (
Diagnostic algorithm
- Connect a professional scan tool; read and record all stored and pending U-codes and any related audio or network codes.
- Verify vehicle battery voltage and charging system are within spec. Recharge or stabilize battery if low and clear codes; attempt to reproduce.
- Check fuses and relays for the audio module and related network nodes; replace if blown and retest.
- Inspect the DACM connector and harness for damage, corrosion, bent pins, or water intrusion. Repair or secure connectors as needed.
- With ignition on, verify power and ground at the DACM connector (backprobe): module should have battery voltage on supply pin and good chassis ground.
- Use a scope or DVOM to measure CANH and CANL at the DACM connector: confirm idle voltages (~2.5 V), differential transitions during bus activity, and proper termination resistance (~60 Ω).
- If CAN lines show short to voltage or ground, trace and repair the shorted section of harness; perform wiggle testing while monitoring bus traffic to find intermittent breaks.
- Check for other modules on the same bus reporting faults. If the DACM is absent on the module list, attempt re-detection by cycling power, clearing codes, or performing a module scan/initialization procedure.
- If wiring and bus are OK but communication is still lost, check for required software updates or module programming. Reflash or reprogram the DACM or gateway per manufacturer procedures.
- If the DACM fails to respond after power/ground/wiring and software checks, consider replacing the DACM. After replacement, program/configure the new module and clear codes, then retest for proper communication.
Likely causes
- Loose or corroded connector at the DACM
- Damaged CAN high/low wiring near door harness or dash area
- Module has lost internal power/ground
- Faulty BCM/gateway not forwarding messages
- Recent repairs or parts replacement left the module unprogrammed
Fault status
Similar codes
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U0194
Lost Communication With “Digital Audio Control Module B”
Causes
- Faulty or disconnected DACM (Digital Audio Control Module B)
- Open, shorted or high-resistance wiring on CAN/LIN communication circuits
- Poor power or ground supply to the DACM
- Blown fuse or relay supplying the module
- Corroded/damaged connectors or pins
- Fault in another network module (BCM, gateway, audio head unit) affecting bus traffic
Symptoms
- No audio or intermittent audio from affected zones
- Audio-related features (phone, navigation, presets) unavailable or showing errors
- Infotainment or radio display may show module missing or communication fault
- One or more related modules report U0194 or other network U-codes
- Possible warning message or chime related to audio or network
What to check
- Read all U-codes and freeze frame with a dealer-level scan tool; note related network codes
- Check battery voltage (should be stable ~12–14 V) and clear low-voltage conditions
- Inspect fuses and relays that feed the DACM and associated network modules
- Visually inspect DACM connector and wiring for corrosion, damage, or loose pins
- Check for physical damage or water intrusion in dash/console areas
- Verify presence of the DACM on the bus with a scan tool (module list)
Signal parameters
- CAN High and CAN Low idle voltage: approximately 2.5 V each; differential ~0 V
- CAN dominant state: CANH ≈ 3.5 V, CANL ≈ 1.5 V (differential ≈ 2.0 V) during activity
- Typical CAN bus data rates: 500 kbps (high speed) or 250 kbps (mid speed) depending on vehicle
- Bus termination: approx. 60 ohms measured across CANH–CANL at key harness connector
- Module supply voltage: battery voltage (approx. 12–14 V) at DACM power pin
- Module ground: continuity to chassis ground with low ohms (
Diagnostic algorithm
- Connect a professional scan tool; read and record all stored and pending U-codes and any related audio or network codes.
- Verify vehicle battery voltage and charging system are within spec. Recharge or stabilize battery if low and clear codes; attempt to reproduce.
- Check fuses and relays for the audio module and related network nodes; replace if blown and retest.
- Inspect the DACM connector and harness for damage, corrosion, bent pins, or water intrusion. Repair or secure connectors as needed.
- With ignition on, verify power and ground at the DACM connector (backprobe): module should have battery voltage on supply pin and good chassis ground.
- Use a scope or DVOM to measure CANH and CANL at the DACM connector: confirm idle voltages (~2.5 V), differential transitions during bus activity, and proper termination resistance (~60 Ω).
- If CAN lines show short to voltage or ground, trace and repair the shorted section of harness; perform wiggle testing while monitoring bus traffic to find intermittent breaks.
- Check for other modules on the same bus reporting faults. If the DACM is absent on the module list, attempt re-detection by cycling power, clearing codes, or performing a module scan/initialization procedure.
- If wiring and bus are OK but communication is still lost, check for required software updates or module programming. Reflash or reprogram the DACM or gateway per manufacturer procedures.
- If the DACM fails to respond after power/ground/wiring and software checks, consider replacing the DACM. After replacement, program/configure the new module and clear codes, then retest for proper communication.
Likely causes
- Loose or corroded connector at the DACM
- Damaged CAN high/low wiring near door harness or dash area
- Module has lost internal power/ground
- Faulty BCM/gateway not forwarding messages
- Recent repairs or parts replacement left the module unprogrammed
Fault status
Similar codes
Manual library for HYUNDAI
Browse 371 HYUNDAI manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
HYUNDAI
-
HYUNDAI: 2023
-
Elantra
-
Elantra N
-
Kona N
-
Tucson
- Hybrid Blue
- Hybrid Limited
- Hybrid SEL Convenience
- Limited, Eng CD G4EN, 4WD
- Limited, Eng CD G4EN, FWD
- Limited, Eng CD G4KN, 4WD
- Limited, Eng CD G4KN, FWD
- N Line, Eng CD G4EN, 4WD
- N Line, Eng CD G4EN, FWD
- N Line, Eng CD G4KN, 4WD
- N Line, Eng CD G4KN, FWD
- Plug-In Hybrid Limited
- Plug-In Hybrid SEL
- SE, Eng CD G4EN, 4WD
- SE, Eng CD G4EN, FWD
- SE, Eng CD G4KN, 4WD
- SE, Eng CD G4KN, FWD
- SEL, Eng CD G4EN, 4WD
- SEL, Eng CD G4EN, FWD
- SEL, Eng CD G4KN, 4WD
- SEL, Eng CD G4KN, FWD
- XRT, Eng CD G4EN, 4WD
- XRT, Eng CD G4EN, FWD
- XRT, Eng CD G4KN, 4WD
- XRT, Eng CD G4KN, FWD
-
-
HYUNDAI: 2022
-
Elantra N
-
Kona N
-
Veloster N
-
HYUNDAI: 2021
-
Veloster N
-
HYUNDAI: 2020
-
Palisade
-
Veloster N
U0194
Lost communication with the digital audio control module - B
Causes
- Faulty or disconnected DACM (Digital Audio Control Module B)
- Open, shorted or high-resistance wiring on CAN/LIN communication circuits
- Poor power or ground supply to the DACM
- Blown fuse or relay supplying the module
- Corroded/damaged connectors or pins
- Fault in another network module (BCM, gateway, audio head unit) affecting bus traffic
Symptoms
- No audio or intermittent audio from affected zones
- Audio-related features (phone, navigation, presets) unavailable or showing errors
- Infotainment or radio display may show module missing or communication fault
- One or more related modules report U0194 or other network U-codes
- Possible warning message or chime related to audio or network
What to check
- Read all U-codes and freeze frame with a dealer-level scan tool; note related network codes
- Check battery voltage (should be stable ~12–14 V) and clear low-voltage conditions
- Inspect fuses and relays that feed the DACM and associated network modules
- Visually inspect DACM connector and wiring for corrosion, damage, or loose pins
- Check for physical damage or water intrusion in dash/console areas
- Verify presence of the DACM on the bus with a scan tool (module list)
Signal parameters
- CAN High and CAN Low idle voltage: approximately 2.5 V each; differential ~0 V
- CAN dominant state: CANH ≈ 3.5 V, CANL ≈ 1.5 V (differential ≈ 2.0 V) during activity
- Typical CAN bus data rates: 500 kbps (high speed) or 250 kbps (mid speed) depending on vehicle
- Bus termination: approx. 60 ohms measured across CANH–CANL at key harness connector
- Module supply voltage: battery voltage (approx. 12–14 V) at DACM power pin
- Module ground: continuity to chassis ground with low ohms (
Diagnostic algorithm
- Connect a professional scan tool; read and record all stored and pending U-codes and any related audio or network codes.
- Verify vehicle battery voltage and charging system are within spec. Recharge or stabilize battery if low and clear codes; attempt to reproduce.
- Check fuses and relays for the audio module and related network nodes; replace if blown and retest.
- Inspect the DACM connector and harness for damage, corrosion, bent pins, or water intrusion. Repair or secure connectors as needed.
- With ignition on, verify power and ground at the DACM connector (backprobe): module should have battery voltage on supply pin and good chassis ground.
- Use a scope or DVOM to measure CANH and CANL at the DACM connector: confirm idle voltages (~2.5 V), differential transitions during bus activity, and proper termination resistance (~60 Ω).
- If CAN lines show short to voltage or ground, trace and repair the shorted section of harness; perform wiggle testing while monitoring bus traffic to find intermittent breaks.
- Check for other modules on the same bus reporting faults. If the DACM is absent on the module list, attempt re-detection by cycling power, clearing codes, or performing a module scan/initialization procedure.
- If wiring and bus are OK but communication is still lost, check for required software updates or module programming. Reflash or reprogram the DACM or gateway per manufacturer procedures.
- If the DACM fails to respond after power/ground/wiring and software checks, consider replacing the DACM. After replacement, program/configure the new module and clear codes, then retest for proper communication.
Likely causes
- Loose or corroded connector at the DACM
- Damaged CAN high/low wiring near door harness or dash area
- Module has lost internal power/ground
- Faulty BCM/gateway not forwarding messages
- Recent repairs or parts replacement left the module unprogrammed
Fault status
Similar codes
Manual library for LAND ROVER
Browse 268 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
LAND ROVER
-
LAND ROVER: 2022
-
Defender
- 90
- 90
- 90 S
- 90 S
- 90 V8
- 90 V8
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- 90 X
- 90 X
- 90 X-Dynamic HSE
- 90 X-Dynamic HSE
- 90 X-Dynamic S
- 90 X-Dynamic S
- 90 X-Dynamic SE
- 90 X-Dynamic SE
- 110
- 110
- 110 S
- 110 S
- 110 SE
- 110 SE
- 110 V8
- 110 V8
- 110 V8 Carpathian Edition
- 110 V8 Carpathian Edition
- 110 X
- 110 X
- 110 X-Dynamic SE
- 110 X-Dynamic SE
- 110 XS Edition
- 110 XS Edition
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Discovery
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Discovery R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Discovery R-Dynamic S
- S
- S
-
Discovery Sport
-
Range Rover
- Autobiography, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover Autobiography
- Autobiography, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover Autobiography
- 2022 Range Rover Base
- 2022 Range Rover Base
- First Edition
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- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover HSE Westminster
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover HSE Westminster
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover SE
- SE, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover SE
- SE, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover SE
- SV
- SV
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
- SVAutobiography Dynamic Blk.
- SVAutobiography Dynamic Blk.
-
Range Rover Evoque
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar S
-
-
LAND ROVER: 2021
-
Discovery
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Discovery R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Discovery R-Dynamic S
- S
- S
-
Discovery Sport
-
Range Rover
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Autobiography
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Autobiography
- Autobiography Fifty Edition
- Autobiography Fifty Edition
- 2021 Range Rover Base
- 2021 Range Rover Base
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover HSE
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover HSE
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover HSE Westminster
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover HSE Westminster
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
- SVAutobiography Dynamic Blk.
- SVAutobiography Dynamic Blk.
-
Range Rover Evoque
-
Range Rover Sport
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography Dynamic
- HSE Dynamic
- HSE Dynamic
- HSE Silver Edition, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Sport HSE Silver Edition
- HST
- HST
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- SE
- SVR
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-
Range Rover Velar
- R-Dynamic HSE
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- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar S
-
LAND ROVER: 2020
-
Discovery
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE
- HSE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE
- HSE Luxury, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE Luxury
- HSE Luxury, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE Luxury
- Landmark
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery SE
- SE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery SE
-
Discovery Sport
-
Range Rover
- Autobiography
- Base, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Base
- Base, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Base
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover HSE
- SVAutobiography
- SVAutobiography Dynamic
-
Range Rover Evoque
-
Range Rover Sport
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport Autobiography Dynamic
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport HSE
- HSE Dynamic
- HSE PHEV
- HST
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport SE
- SVR
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar S
- S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar S
- SVAutobiography Dyn.
-
LAND ROVER: 2019
