Code
U0197
Generic
U — Network/User
Lost Communication With Telephone Control Module
Views:
UK: 16
EN: 32
RU: 27
AI status
Completed
Completed
100%
Causes
- Telephone control module failure
- Loss of module power or ground (blown fuse, disconnected/failed power feed)
- Damaged or disconnected wiring or connectors to the module
- CAN/LIN bus wiring fault (open, short to ground/power, high resistance)
- Network termination or bus short (low resistance or missing termination)
- Battery low voltage or poor battery connections
Symptoms
- Loss of hands-free phone, Bluetooth, or telematics services (SOS, concierge)
- Telematics or phone menu/options disabled or not responding
- Warning or communication error messages on the instrument cluster or infotainment screen
- Other network-related features not functioning if the module shared the bus
- Stored U0197 code and possibly other network communication DTCs
What to check
- Scan vehicle for U0197 and any related U0xxx codes; record freeze frame and history data
- Check battery voltage (key on and cranking) and battery connections
- Verify fuses and relays powering the telephone control module
- Visually inspect the module connectors and wiring for damage, corrosion, or water intrusion
- Check for presence of the module in the scanner’s module list (does tool detect the module?)
- Measure CAN bus voltages at the module connector (CAN_H, CAN_L) with key on, engine off
Signal parameters
- CAN bus recessive voltages: CAN_H ≈ 2.5 V, CAN_L ≈ 2.5 V (idle)
- CAN bus dominant voltages: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (during transmission) — verify with scope
- Expected bus termination: total ≈ 60 Ω across CAN_H and CAN_L
- Typical CAN data rate: 250 kb/s or 500 kb/s depending on vehicle (check OEM spec)
- Module should respond to diagnostic request frames; absence indicates no communication
Diagnostic algorithm
- Retrieve and record all network communication DTCs and freeze frame data.
- Confirm battery voltage is within specification (≥12.4 V at rest); retest after charging if low.
- Inspect fuses and wiring for the telephone control module; replace any blown fuses and repair visible damage.
- With ignition on, confirm power and ground at the module connector (measure pin voltages).
- Check connector integrity: disconnect, inspect pins for corrosion/bent pins, then reconnect securely.
- Check CAN bus presence at the module: measure CAN_H and CAN_L with a multimeter and verify against expected idle voltages.
- Use an oscilloscope or CAN bus analyzer to view frames on the bus and confirm whether the telephone module transmits or receives frames. Look for bus errors or bus-off conditions.
- Measure termination resistance across CAN_H and CAN_L; repair missing or incorrect terminators.
- If wiring is suspect, perform continuity and short-to-power/ground tests from the module connector to the next nodes and to chassis ground.
- Isolate network segments if possible (disconnect nearby modules or harness branches) to identify a faulty device causing bus issues.
- If wiring and power/ground are good but no communication, verify software/firmware version and reflash or update the module per OEM procedures if available.
- If module fails to communicate after all checks and known-good network present, consider replacing the telephone control module and program it per manufacturer procedure.
Likely causes
- Blown fuse or disconnected power/ground to the telephone control module
- Damaged connector pins or corrosion at the module harness
- Open or shorted CAN bus wiring near the telephone module
- Telephone module hardware failure
- Another module placed the network in bus-off or collision state
Fault status
Status
Lost communication with the Telephone Control Module — no responses received from the telematics/phone module on the vehicle data bus.
Repair difficulty: Medium
Diagnostic time: 1.5-3.5 hours
Workshop Manuals
Available brands with manuals
2
AUDI 11
6-speed manual gearbox 0B1, front-wheel drive — Workshop Manual (Edition 05.2014)
Workshop Manual199,00 UAH
Audi A3 (1997) – 1.6L 4-cylinder (2‑valve) Engine Mechanical Components Service Manual (AEH, AKL, APF) – Edition 07.2002
Workshop Manual199,00 UAH
AUDI A3 (2004) Workshop Manual — 2.0L FSI Turbo (4‑cyl, 4‑valve) Engine, Mechanics — Edition 03.2017
Workshop Manual199,00 UAH
Audi A3 2004 — Electrical System (Workshop Manual, Edition 02.2018)
Workshop Manual199,00 UAH
Audi A4 / A4 Cabriolet – 4.2 l V8 (5‑valve, timing chains) – Workshop Manual (Mechanics) – Edition 04.2007
Workshop Manual199,00 UAH
Audi A4 / A4 Cabriolet — Auxiliary Heater Workshop Manual (Edition 08.2004)
Workshop Manual199,00 UAH
Audi A4 / A4 Cabriolet (1.8T 4‑cyl turbo) — Motronic Injection & Ignition System Service Manual (Edition 01.2015)
Workshop Manual199,00 UAH
Audi A8 (2003) — Electrical System Workshop Manual (Edition 08.2014)
Workshop Manual199,00 UAH
Audi Q4 e-tron (Type F4) - Self-study Programme SSP 685
Workshop Manual199,00 UAH
Audi Q8 (2018) — Electrical System Workshop Manual (Edition 05.2019)
Workshop Manual199,00 UAH
Audi Servicing Manual — 7‑Speed Dual Clutch Transmission 0CJ / 0CL / 0CK / 0DN / 0DP / 0HL (Edition 05.2018)
Workshop Manual199,00 UAH
LAND ROVER 3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop Manual199,00 UAH
Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop Manual199,00 UAH
Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop Manual199,00 UAH
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Code
U0197
HYUNDAI
U — Network/User
Lost Communication With Telephone Control Module
Views:
UK: 12
EN: 16
RU: 15
AI status
Completed
Completed
100%
Causes
- Telephone control module failure
- Loss of module power or ground (blown fuse, disconnected/failed power feed)
- Damaged or disconnected wiring or connectors to the module
- CAN/LIN bus wiring fault (open, short to ground/power, high resistance)
- Network termination or bus short (low resistance or missing termination)
- Battery low voltage or poor battery connections
Symptoms
- Loss of hands-free phone, Bluetooth, or telematics services (SOS, concierge)
- Telematics or phone menu/options disabled or not responding
- Warning or communication error messages on the instrument cluster or infotainment screen
- Other network-related features not functioning if the module shared the bus
- Stored U0197 code and possibly other network communication DTCs
What to check
- Scan vehicle for U0197 and any related U0xxx codes; record freeze frame and history data
- Check battery voltage (key on and cranking) and battery connections
- Verify fuses and relays powering the telephone control module
- Visually inspect the module connectors and wiring for damage, corrosion, or water intrusion
- Check for presence of the module in the scanner’s module list (does tool detect the module?)
- Measure CAN bus voltages at the module connector (CAN_H, CAN_L) with key on, engine off
Signal parameters
- CAN bus recessive voltages: CAN_H ≈ 2.5 V, CAN_L ≈ 2.5 V (idle)
- CAN bus dominant voltages: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (during transmission) — verify with scope
- Expected bus termination: total ≈ 60 Ω across CAN_H and CAN_L
- Typical CAN data rate: 250 kb/s or 500 kb/s depending on vehicle (check OEM spec)
- Module should respond to diagnostic request frames; absence indicates no communication
Diagnostic algorithm
- Retrieve and record all network communication DTCs and freeze frame data.
- Confirm battery voltage is within specification (≥12.4 V at rest); retest after charging if low.
- Inspect fuses and wiring for the telephone control module; replace any blown fuses and repair visible damage.
- With ignition on, confirm power and ground at the module connector (measure pin voltages).
- Check connector integrity: disconnect, inspect pins for corrosion/bent pins, then reconnect securely.
- Check CAN bus presence at the module: measure CAN_H and CAN_L with a multimeter and verify against expected idle voltages.
- Use an oscilloscope or CAN bus analyzer to view frames on the bus and confirm whether the telephone module transmits or receives frames. Look for bus errors or bus-off conditions.
- Measure termination resistance across CAN_H and CAN_L; repair missing or incorrect terminators.
- If wiring is suspect, perform continuity and short-to-power/ground tests from the module connector to the next nodes and to chassis ground.
- Isolate network segments if possible (disconnect nearby modules or harness branches) to identify a faulty device causing bus issues.
- If wiring and power/ground are good but no communication, verify software/firmware version and reflash or update the module per OEM procedures if available.
- If module fails to communicate after all checks and known-good network present, consider replacing the telephone control module and program it per manufacturer procedure.
Likely causes
- Blown fuse or disconnected power/ground to the telephone control module
- Damaged connector pins or corrosion at the module harness
- Open or shorted CAN bus wiring near the telephone module
- Telephone module hardware failure
- Another module placed the network in bus-off or collision state
Fault status
Status
Lost communication with the Telephone Control Module — no responses received from the telematics/phone module on the vehicle data bus.
Repair difficulty: Medium
Diagnostic time: 1.5-3.5 hours
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Was this AI description helpful?
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Code
U0197
LAND ROVER
U — Network/User
Lost communication with the phone control module
Views:
UK: 7
EN: 14
RU: 11
AI status
Completed
Completed
100%
Causes
- Telephone control module failure
- Loss of module power or ground (blown fuse, disconnected/failed power feed)
- Damaged or disconnected wiring or connectors to the module
- CAN/LIN bus wiring fault (open, short to ground/power, high resistance)
- Network termination or bus short (low resistance or missing termination)
- Battery low voltage or poor battery connections
Symptoms
- Loss of hands-free phone, Bluetooth, or telematics services (SOS, concierge)
- Telematics or phone menu/options disabled or not responding
- Warning or communication error messages on the instrument cluster or infotainment screen
- Other network-related features not functioning if the module shared the bus
- Stored U0197 code and possibly other network communication DTCs
What to check
- Scan vehicle for U0197 and any related U0xxx codes; record freeze frame and history data
- Check battery voltage (key on and cranking) and battery connections
- Verify fuses and relays powering the telephone control module
- Visually inspect the module connectors and wiring for damage, corrosion, or water intrusion
- Check for presence of the module in the scanner’s module list (does tool detect the module?)
- Measure CAN bus voltages at the module connector (CAN_H, CAN_L) with key on, engine off
Signal parameters
- CAN bus recessive voltages: CAN_H ≈ 2.5 V, CAN_L ≈ 2.5 V (idle)
- CAN bus dominant voltages: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (during transmission) — verify with scope
- Expected bus termination: total ≈ 60 Ω across CAN_H and CAN_L
- Typical CAN data rate: 250 kb/s or 500 kb/s depending on vehicle (check OEM spec)
- Module should respond to diagnostic request frames; absence indicates no communication
Diagnostic algorithm
- Retrieve and record all network communication DTCs and freeze frame data.
- Confirm battery voltage is within specification (≥12.4 V at rest); retest after charging if low.
- Inspect fuses and wiring for the telephone control module; replace any blown fuses and repair visible damage.
- With ignition on, confirm power and ground at the module connector (measure pin voltages).
- Check connector integrity: disconnect, inspect pins for corrosion/bent pins, then reconnect securely.
- Check CAN bus presence at the module: measure CAN_H and CAN_L with a multimeter and verify against expected idle voltages.
- Use an oscilloscope or CAN bus analyzer to view frames on the bus and confirm whether the telephone module transmits or receives frames. Look for bus errors or bus-off conditions.
- Measure termination resistance across CAN_H and CAN_L; repair missing or incorrect terminators.
- If wiring is suspect, perform continuity and short-to-power/ground tests from the module connector to the next nodes and to chassis ground.
- Isolate network segments if possible (disconnect nearby modules or harness branches) to identify a faulty device causing bus issues.
- If wiring and power/ground are good but no communication, verify software/firmware version and reflash or update the module per OEM procedures if available.
- If module fails to communicate after all checks and known-good network present, consider replacing the telephone control module and program it per manufacturer procedure.
Likely causes
- Blown fuse or disconnected power/ground to the telephone control module
- Damaged connector pins or corrosion at the module harness
- Open or shorted CAN bus wiring near the telephone module
- Telephone module hardware failure
- Another module placed the network in bus-off or collision state
Fault status
Status
Lost communication with the Telephone Control Module — no responses received from the telematics/phone module on the vehicle data bus.
Repair difficulty: Medium
Diagnostic time: 1.5-3.5 hours
Workshop Manuals
Repair manuals for LAND ROVER
3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop Manual199,00 UAH
Land Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop Manual199,00 UAH
Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop Manual199,00 UAH
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
U0197
MERCEDES-BENZ
U — Network/User
Lost Communication with Telephone Control Module
Views:
UK: 13
EN: 25
RU: 19
AI status
Completed
Completed
100%
Causes
- Telephone control module failure
- Loss of module power or ground (blown fuse, disconnected/failed power feed)
- Damaged or disconnected wiring or connectors to the module
- CAN/LIN bus wiring fault (open, short to ground/power, high resistance)
- Network termination or bus short (low resistance or missing termination)
- Battery low voltage or poor battery connections
Symptoms
- Loss of hands-free phone, Bluetooth, or telematics services (SOS, concierge)
- Telematics or phone menu/options disabled or not responding
- Warning or communication error messages on the instrument cluster or infotainment screen
- Other network-related features not functioning if the module shared the bus
- Stored U0197 code and possibly other network communication DTCs
What to check
- Scan vehicle for U0197 and any related U0xxx codes; record freeze frame and history data
- Check battery voltage (key on and cranking) and battery connections
- Verify fuses and relays powering the telephone control module
- Visually inspect the module connectors and wiring for damage, corrosion, or water intrusion
- Check for presence of the module in the scanner’s module list (does tool detect the module?)
- Measure CAN bus voltages at the module connector (CAN_H, CAN_L) with key on, engine off
Signal parameters
- CAN bus recessive voltages: CAN_H ≈ 2.5 V, CAN_L ≈ 2.5 V (idle)
- CAN bus dominant voltages: CAN_H ≈ 3.5 V, CAN_L ≈ 1.5 V (during transmission) — verify with scope
- Expected bus termination: total ≈ 60 Ω across CAN_H and CAN_L
- Typical CAN data rate: 250 kb/s or 500 kb/s depending on vehicle (check OEM spec)
- Module should respond to diagnostic request frames; absence indicates no communication
Diagnostic algorithm
- Retrieve and record all network communication DTCs and freeze frame data.
- Confirm battery voltage is within specification (≥12.4 V at rest); retest after charging if low.
- Inspect fuses and wiring for the telephone control module; replace any blown fuses and repair visible damage.
- With ignition on, confirm power and ground at the module connector (measure pin voltages).
- Check connector integrity: disconnect, inspect pins for corrosion/bent pins, then reconnect securely.
- Check CAN bus presence at the module: measure CAN_H and CAN_L with a multimeter and verify against expected idle voltages.
- Use an oscilloscope or CAN bus analyzer to view frames on the bus and confirm whether the telephone module transmits or receives frames. Look for bus errors or bus-off conditions.
- Measure termination resistance across CAN_H and CAN_L; repair missing or incorrect terminators.
- If wiring is suspect, perform continuity and short-to-power/ground tests from the module connector to the next nodes and to chassis ground.
- Isolate network segments if possible (disconnect nearby modules or harness branches) to identify a faulty device causing bus issues.
- If wiring and power/ground are good but no communication, verify software/firmware version and reflash or update the module per OEM procedures if available.
- If module fails to communicate after all checks and known-good network present, consider replacing the telephone control module and program it per manufacturer procedure.
Likely causes
- Blown fuse or disconnected power/ground to the telephone control module
- Damaged connector pins or corrosion at the module harness
- Open or shorted CAN bus wiring near the telephone module
- Telephone module hardware failure
- Another module placed the network in bus-off or collision state
Fault status
Status
Lost communication with the Telephone Control Module — no responses received from the telematics/phone module on the vehicle data bus.
Repair difficulty: Medium
Diagnostic time: 1.5-3.5 hours
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
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0
Send to email