Code
U2150
HUMMER
U — Network/User
Navigation ECU Gateway Communication Error
Views:
UK: 19
EN: 27
RU: 22
AI status
Completed
Completed
100%
Causes
- Damaged or corroded connector at Navigation ECU or gateway module
- Broken or shorted CAN bus wiring (CANH/CANL) between Navigation ECU and gateway
- Missing or intermittent power or ground to the Navigation ECU
- Faulty CAN transceiver inside the Navigation ECU or gateway module
- Improper or missing termination resistor on the CAN bus
- Software/configuration mismatch or corrupted module programming
Symptoms
- Navigation unit partially or completely inoperative (no maps, no guidance)
- Other modules reporting communication-related DTCs or network errors
- Intermittent features tied to navigation (audio prompts, Bluetooth nav prompts) failing
- Instrument cluster or infotainment showing network warnings
- Possible no GPS display updates or frozen map screen
What to check
- Retrieve and record DTCs from all modules with a capable scan tool; note freeze-frame and occurrence count
- Inspect Navigation ECU and gateway connectors for corrosion, bent pins, water intrusion, or damage
- Verify battery voltage and ground integrity at the Navigation ECU with ignition ON
- Measure CANH and CANL voltages at the Navigation ECU connector with key ON (engine off)
- Measure DC resistance between CANH and CANL with ignition OFF (expected ≈60Ω if two 120Ω terminators present)
- Check for shorts to battery or chassis ground on CANH/CANL
Signal parameters
- Vehicle battery nominal supply at module: ~12 V (verify 11–14 V depending on state)
- CAN bus idle (recessive): CANH ≈ 2.5 V, CANL ≈ 2.5 V
- CAN bus dominant: CANH ≈ 3.5 V, CANL ≈ 1.5 V (differential ≈2 V)
- Termination resistance across CANH–CANL with ignition OFF: ≈60 Ω (two 120 Ω terminators in parallel)
- Typical high-speed CAN data rates: 250 kb/s or 500 kb/s (verify specific vehicle network rate with factory data)
- No DC short between CANH/CANL and battery or chassis ground
Diagnostic algorithm
- Connect a factory-level or equivalent scan tool. Read and log all network DTCs and module communication status; note freeze-frame data and occurrence conditions.
- Clear the DTC and see if it returns; determine if fault is intermittent or constant.
- Visually inspect Navigation ECU and gateway connectors, wiring harness, and nearby components for damage, corrosion, or water intrusion.
- Verify power and ground at the Navigation ECU pins with ignition ON. Repair any low voltage or bad ground before further testing.
- With ignition ON (engine off), measure CANH and CANL voltages at the Navigation ECU connector. Compare to expected values in signal_params.
- With ignition OFF, measure resistance across CANH–CANL at the same connector. Expect ≈60 Ω. If open or unusually high/low, trace wiring and check terminators.
- Use a scan tool to observe live CAN messages. If Navigation messages are absent but other modules communicate, the problem is likely module-specific or wiring to that module.
- Use an oscilloscope to inspect waveform quality on CANH and CANL if available. Look for glitching, excessive noise, or missing dominant/recessive transitions.
- Isolate the circuit: disconnect the Navigation ECU (with ignition OFF) and verify whether the rest of the bus returns to normal. If disconnecting one module restores network, suspect that module.
- Repair any identified wiring faults, damaged connectors, poor grounds, or replace blown fuses. If wiring and power/ground are good and the module still does not communicate, consider module replacement or reprogramming per manufacturer procedures.
- After repairs or replacements, reprogram/configure modules as required, clear codes, and verify restoration of normal communication; perform functional test/road test as applicable.
Likely causes
- Loose or corroded connector or pin at Navigation ECU
- Open or short in the local CAN wiring harness
- Failed Navigation ECU CAN transceiver
- Faulty gateway/module that routes messages between networks
- Blown fuse or lost power/ground to Navigation ECU
Fault status
Status
Navigation ECU Gateway Communication Error — The Navigation module failed to send/receive expected gateway network messages. Stored when the gateway or navigation unit messages time out, are missing, or are corrupted. May be intermittent or permanent depending on wiring, power, or module condition.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Similar codes
Repair manuals
Manual library for HUMMER
69
Browse 69 HUMMER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
HUMMER
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