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Home / DTC / U0104 — Lost Communication With Cruise Control Module

U0104 — Lost Communication With Cruise Control Module

Detailed page for trouble code U0104.

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U0104

Generic U — Network/User

Lost Communication With Cruise Control Module

Brand: Generic
Type: U — Network/User
Views: UK: 38 EN: 35 RU: 58
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open or shorted wiring to the cruise control module (CAN high/low, power, ground)
  • Blown fuse or faulty power/ignition feed to the module
  • Corroded or loose connector at the cruise control module
  • Failed cruise control module
  • CAN bus wiring shorted to chassis or battery
  • Missing or failed CAN bus termination (open/incorrect resistance)

Symptoms

  • Cruise control inoperative or unavailable
  • Cruise control warning or message on instrument cluster
  • One or more network communication DTCs present
  • Related systems that share the network may show errors or reduced functionality
  • Inconsistent or intermittent module response to scan tool

What to check

  • Verify code with a full OBD-II scan tool and record freeze frame and related U-codes
  • Check battery voltage (should be ~12–14 V) and charging system health
  • Inspect and test fuses/relays for cruise control and instrument/communication bus
  • Visually inspect module connector for corrosion, bent pins, water intrusion
  • Scan all modules to see if multiple modules report network faults (bus-off, U-codes)
  • Measure CAN H and CAN L voltages at the cruise control connector with key ON

Signal parameters

  • CAN_H idle ≈ 2.5 V (dominant ~3.5 V)
  • CAN_L idle ≈ 2.5 V (dominant ~1.5 V)
  • Differential CAN voltage: ≈ 0 V idle, ≈ 2 V dominant
  • Termination resistance across CAN_H and CAN_L ≈ 60 Ω (two 120 Ω terminators in parallel)
  • Module supply voltage (Vbatt/ignition feed) ≈ 9–14 V when key on
  • Module ground continuity near 0 Ω to chassis

Diagnostic algorithm

  1. Confirm the U0104 code and note if it is current, historic, or intermittent. Check freeze frame and related U-codes.
  2. Verify battery voltage and charging system; low voltage can cause communication faults. Recharge or test battery if necessary.
  3. Scan all control modules to identify other communication errors or a module reporting bus-off. Record all module responses.
  4. Check fuses and ignition-switched power feeding the cruise control module and related networks. Repair any open circuits.
  5. Visually inspect the cruise control module connector and wiring harness for corrosion, damage, or pin damage. Repair or clean as required.
  6. With key ON (per manufacturer safety procedures), backprobe the module connector and measure CAN_H and CAN_L voltages and differential. Compare to expected signal parameters.
  7. Measure termination resistance across CAN_H and CAN_L near the module (≈ 60 Ω). If open or incorrect, trace to missing/failed terminators.
  8. Check ground and power pin continuity to their chassis/power sources. Repair any high-resistance connections.
  9. If intermittent, perform wiggle tests on harness and connectors while monitoring communication. Use a scope or serial-data display to watch message traffic if available.
  10. If another module is forcing the bus off, isolate by disconnecting suspect modules one at a time (follow safe manufacturer procedures) to identify the faulted node.
  11. If wiring and power/ground are good but the module does not respond to the scan tool, consider module failure or software/configuration mismatch. Verify correct part number and software level before replacement.
  12. After repairs, clear codes and re-check for reoccurrence. Road test and re-scan to confirm resolution.

Likely causes

  • Loose or corroded connector at the cruise control module
  • Blown fuse or lost ignition feed to the cruise module
  • Shorted or open CAN H/L wiring in harness (damage, pinched, rodent)
  • Failed cruise control module electronics
  • Faulty ground at module chassis point
  • Another failed module causing network communication failure

Fault status

⚠️ Status
Stored when the vehicle communication network (e.g., CAN) does not receive expected responses from the Cruise Control Module during key-on/run. May be set as intermittent or continuous and often appears with other network-related U-codes.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

U0100 U0101 U0121 U0140 U0073
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Code

U0104

HYUNDAI U — Network/User

Lost Communication With Cruise Control Module | ECM-Cruise Control Module Communication

Brand: HYUNDAI
Type: U — Network/User
Views: UK: 25 EN: 22 RU: 53
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open or shorted wiring to the cruise control module (CAN high/low, power, ground)
  • Blown fuse or faulty power/ignition feed to the module
  • Corroded or loose connector at the cruise control module
  • Failed cruise control module
  • CAN bus wiring shorted to chassis or battery
  • Missing or failed CAN bus termination (open/incorrect resistance)

Symptoms

  • Cruise control inoperative or unavailable
  • Cruise control warning or message on instrument cluster
  • One or more network communication DTCs present
  • Related systems that share the network may show errors or reduced functionality
  • Inconsistent or intermittent module response to scan tool

What to check

  • Verify code with a full OBD-II scan tool and record freeze frame and related U-codes
  • Check battery voltage (should be ~12–14 V) and charging system health
  • Inspect and test fuses/relays for cruise control and instrument/communication bus
  • Visually inspect module connector for corrosion, bent pins, water intrusion
  • Scan all modules to see if multiple modules report network faults (bus-off, U-codes)
  • Measure CAN H and CAN L voltages at the cruise control connector with key ON

Signal parameters

  • CAN_H idle ≈ 2.5 V (dominant ~3.5 V)
  • CAN_L idle ≈ 2.5 V (dominant ~1.5 V)
  • Differential CAN voltage: ≈ 0 V idle, ≈ 2 V dominant
  • Termination resistance across CAN_H and CAN_L ≈ 60 Ω (two 120 Ω terminators in parallel)
  • Module supply voltage (Vbatt/ignition feed) ≈ 9–14 V when key on
  • Module ground continuity near 0 Ω to chassis

Diagnostic algorithm

  1. Confirm the U0104 code and note if it is current, historic, or intermittent. Check freeze frame and related U-codes.
  2. Verify battery voltage and charging system; low voltage can cause communication faults. Recharge or test battery if necessary.
  3. Scan all control modules to identify other communication errors or a module reporting bus-off. Record all module responses.
  4. Check fuses and ignition-switched power feeding the cruise control module and related networks. Repair any open circuits.
  5. Visually inspect the cruise control module connector and wiring harness for corrosion, damage, or pin damage. Repair or clean as required.
  6. With key ON (per manufacturer safety procedures), backprobe the module connector and measure CAN_H and CAN_L voltages and differential. Compare to expected signal parameters.
  7. Measure termination resistance across CAN_H and CAN_L near the module (≈ 60 Ω). If open or incorrect, trace to missing/failed terminators.
  8. Check ground and power pin continuity to their chassis/power sources. Repair any high-resistance connections.
  9. If intermittent, perform wiggle tests on harness and connectors while monitoring communication. Use a scope or serial-data display to watch message traffic if available.
  10. If another module is forcing the bus off, isolate by disconnecting suspect modules one at a time (follow safe manufacturer procedures) to identify the faulted node.
  11. If wiring and power/ground are good but the module does not respond to the scan tool, consider module failure or software/configuration mismatch. Verify correct part number and software level before replacement.
  12. After repairs, clear codes and re-check for reoccurrence. Road test and re-scan to confirm resolution.

Likely causes

  • Loose or corroded connector at the cruise control module
  • Blown fuse or lost ignition feed to the cruise module
  • Shorted or open CAN H/L wiring in harness (damage, pinched, rodent)
  • Failed cruise control module electronics
  • Faulty ground at module chassis point
  • Another failed module causing network communication failure

Fault status

⚠️ Status
Stored when the vehicle communication network (e.g., CAN) does not receive expected responses from the Cruise Control Module during key-on/run. May be set as intermittent or continuous and often appears with other network-related U-codes.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

U0100 U0101 U0121 U0140 U0073
Your experience will help others
+100 karma for a short comment :)
Keep it short and practical. Up to 500 characters.
Send to email
Code

U0104

LAND ROVER U — Network/User

Lost communication with the speed control module

Brand: LAND ROVER
Type: U — Network/User
Views: UK: 14 EN: 13 RU: 39
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Open or shorted wiring to the cruise control module (CAN high/low, power, ground)
  • Blown fuse or faulty power/ignition feed to the module
  • Corroded or loose connector at the cruise control module
  • Failed cruise control module
  • CAN bus wiring shorted to chassis or battery
  • Missing or failed CAN bus termination (open/incorrect resistance)

Symptoms

  • Cruise control inoperative or unavailable
  • Cruise control warning or message on instrument cluster
  • One or more network communication DTCs present
  • Related systems that share the network may show errors or reduced functionality
  • Inconsistent or intermittent module response to scan tool

What to check

  • Verify code with a full OBD-II scan tool and record freeze frame and related U-codes
  • Check battery voltage (should be ~12–14 V) and charging system health
  • Inspect and test fuses/relays for cruise control and instrument/communication bus
  • Visually inspect module connector for corrosion, bent pins, water intrusion
  • Scan all modules to see if multiple modules report network faults (bus-off, U-codes)
  • Measure CAN H and CAN L voltages at the cruise control connector with key ON

Signal parameters

  • CAN_H idle ≈ 2.5 V (dominant ~3.5 V)
  • CAN_L idle ≈ 2.5 V (dominant ~1.5 V)
  • Differential CAN voltage: ≈ 0 V idle, ≈ 2 V dominant
  • Termination resistance across CAN_H and CAN_L ≈ 60 Ω (two 120 Ω terminators in parallel)
  • Module supply voltage (Vbatt/ignition feed) ≈ 9–14 V when key on
  • Module ground continuity near 0 Ω to chassis

Diagnostic algorithm

  1. Confirm the U0104 code and note if it is current, historic, or intermittent. Check freeze frame and related U-codes.
  2. Verify battery voltage and charging system; low voltage can cause communication faults. Recharge or test battery if necessary.
  3. Scan all control modules to identify other communication errors or a module reporting bus-off. Record all module responses.
  4. Check fuses and ignition-switched power feeding the cruise control module and related networks. Repair any open circuits.
  5. Visually inspect the cruise control module connector and wiring harness for corrosion, damage, or pin damage. Repair or clean as required.
  6. With key ON (per manufacturer safety procedures), backprobe the module connector and measure CAN_H and CAN_L voltages and differential. Compare to expected signal parameters.
  7. Measure termination resistance across CAN_H and CAN_L near the module (≈ 60 Ω). If open or incorrect, trace to missing/failed terminators.
  8. Check ground and power pin continuity to their chassis/power sources. Repair any high-resistance connections.
  9. If intermittent, perform wiggle tests on harness and connectors while monitoring communication. Use a scope or serial-data display to watch message traffic if available.
  10. If another module is forcing the bus off, isolate by disconnecting suspect modules one at a time (follow safe manufacturer procedures) to identify the faulted node.
  11. If wiring and power/ground are good but the module does not respond to the scan tool, consider module failure or software/configuration mismatch. Verify correct part number and software level before replacement.
  12. After repairs, clear codes and re-check for reoccurrence. Road test and re-scan to confirm resolution.

Likely causes

  • Loose or corroded connector at the cruise control module
  • Blown fuse or lost ignition feed to the cruise module
  • Shorted or open CAN H/L wiring in harness (damage, pinched, rodent)
  • Failed cruise control module electronics
  • Faulty ground at module chassis point
  • Another failed module causing network communication failure

Fault status

⚠️ Status
Stored when the vehicle communication network (e.g., CAN) does not receive expected responses from the Cruise Control Module during key-on/run. May be set as intermittent or continuous and often appears with other network-related U-codes.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

U0100 U0101 U0121 U0140 U0073
Workshop Manuals

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Land Rover Defender 300Tdi — Workshop Manual (1996 model year)

Workshop Manual
Defender 300Tdi Years: 1996 Manual in English 7.5 MB
Short description

Official workshop manual for the Land Rover Defender 300Tdi (from 1996 model year). Contains specifications, adjustment, fault diagnosis and step-by-step repair and overhaul procedures for engine, transmission, axles, suspension, brakes, electrical and body. Intended for dealer workshops and trained technicians.

199,00 UAH
Contents
Key sections:
  • 01 INTRODUCTION
  • 04 GENERAL SPECIFICATION DATA
  • 05 ENGINE TUNING DATA
  • 07 GENERAL FITTING REMINDERS
  • 09 LUBRICANTS, FLUIDS AND CAPACITIES
  • 10 MAINTENANCE
  • 12 ENGINE Tdi
  • - Description and operation
  • - Fault diagnosis
  • - Adjustment
  • - Repair and overhaul procedures
  • 19 FUEL SYSTEM Tdi
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Workshop Manual
Defender Years: 1999–2002 Manual in English 7.6 MB
Short description

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199,00 UAH
Contents
Key sections:
  • 01 - INTRODUCTION
  • - Introduction
  • - Dimensions
  • - References
  • - Repairs and replacements
  • - Poisonous substances
  • - Fuel handling precautions
  • - Synthetic rubber
  • - Recommended sealants
  • - Used engine oil precautions
  • - Accessories and conversions
  • - Wheels and tyres
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Land Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)

Workshop Manual
Manual in English Pages: 494 7.1 MB
Short description

Land Rover Range Rover Electrical Library (LRL 0453ENG). Comprehensive manual covering fuse details, earth points, system descriptions, diagnostics and connector pin-outs for electrical troubleshooting and repair. Intended for technicians and service workshops.

199,00 UAH
Contents
Key sections:
  • 1 INTRODUCTION
  • 1.1 About this document
  • 1.2 Battery voltage
  • 1.3 Electrical precautions
  • 1.4 Battery disconnecting / charging
  • 1.5 Disciplines / greases
  • 1.6 Abbreviations
  • 1.7 HeVAC, sensors abbreviations
  • 1.8 How to use this document
  • 1.9 Connector detail format
  • 1.10 Fault diagnosis
  • 1.11 Wire colour codes
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Code

U0104

MERCEDES-BENZ U — Network/User

Lost Communication with Cruise Control Module

Brand: MERCEDES-BENZ
Type: U — Network/User
Views: UK: 30 EN: 28 RU: 47
AI status
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Page language: EN

Causes

  • Open or shorted wiring to the cruise control module (CAN high/low, power, ground)
  • Blown fuse or faulty power/ignition feed to the module
  • Corroded or loose connector at the cruise control module
  • Failed cruise control module
  • CAN bus wiring shorted to chassis or battery
  • Missing or failed CAN bus termination (open/incorrect resistance)

Symptoms

  • Cruise control inoperative or unavailable
  • Cruise control warning or message on instrument cluster
  • One or more network communication DTCs present
  • Related systems that share the network may show errors or reduced functionality
  • Inconsistent or intermittent module response to scan tool

What to check

  • Verify code with a full OBD-II scan tool and record freeze frame and related U-codes
  • Check battery voltage (should be ~12–14 V) and charging system health
  • Inspect and test fuses/relays for cruise control and instrument/communication bus
  • Visually inspect module connector for corrosion, bent pins, water intrusion
  • Scan all modules to see if multiple modules report network faults (bus-off, U-codes)
  • Measure CAN H and CAN L voltages at the cruise control connector with key ON

Signal parameters

  • CAN_H idle ≈ 2.5 V (dominant ~3.5 V)
  • CAN_L idle ≈ 2.5 V (dominant ~1.5 V)
  • Differential CAN voltage: ≈ 0 V idle, ≈ 2 V dominant
  • Termination resistance across CAN_H and CAN_L ≈ 60 Ω (two 120 Ω terminators in parallel)
  • Module supply voltage (Vbatt/ignition feed) ≈ 9–14 V when key on
  • Module ground continuity near 0 Ω to chassis

Diagnostic algorithm

  1. Confirm the U0104 code and note if it is current, historic, or intermittent. Check freeze frame and related U-codes.
  2. Verify battery voltage and charging system; low voltage can cause communication faults. Recharge or test battery if necessary.
  3. Scan all control modules to identify other communication errors or a module reporting bus-off. Record all module responses.
  4. Check fuses and ignition-switched power feeding the cruise control module and related networks. Repair any open circuits.
  5. Visually inspect the cruise control module connector and wiring harness for corrosion, damage, or pin damage. Repair or clean as required.
  6. With key ON (per manufacturer safety procedures), backprobe the module connector and measure CAN_H and CAN_L voltages and differential. Compare to expected signal parameters.
  7. Measure termination resistance across CAN_H and CAN_L near the module (≈ 60 Ω). If open or incorrect, trace to missing/failed terminators.
  8. Check ground and power pin continuity to their chassis/power sources. Repair any high-resistance connections.
  9. If intermittent, perform wiggle tests on harness and connectors while monitoring communication. Use a scope or serial-data display to watch message traffic if available.
  10. If another module is forcing the bus off, isolate by disconnecting suspect modules one at a time (follow safe manufacturer procedures) to identify the faulted node.
  11. If wiring and power/ground are good but the module does not respond to the scan tool, consider module failure or software/configuration mismatch. Verify correct part number and software level before replacement.
  12. After repairs, clear codes and re-check for reoccurrence. Road test and re-scan to confirm resolution.

Likely causes

  • Loose or corroded connector at the cruise control module
  • Blown fuse or lost ignition feed to the cruise module
  • Shorted or open CAN H/L wiring in harness (damage, pinched, rodent)
  • Failed cruise control module electronics
  • Faulty ground at module chassis point
  • Another failed module causing network communication failure

Fault status

⚠️ Status
Stored when the vehicle communication network (e.g., CAN) does not receive expected responses from the Cruise Control Module during key-on/run. May be set as intermittent or continuous and often appears with other network-related U-codes.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 1.0-3.0 hours

Similar codes

U0100 U0101 U0121 U0140 U0073
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