U1039

Code

LAND ROVER U — Network/User

SCP (J1850) invalid or missing data for vehicle speed

Brand: LAND ROVER

Type: U — Network/User

Views: UK: 17 EN: 27 RU: 22

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Lost or intermittent SCP (J1850) network communication for vehicle speed
Faulty wheel speed sensor or ABS module not producing speed message
Damaged wiring or connectors in speed-sensor or network circuits
Corroded ground or supply to ABS/BCM/instrument cluster
Module software/firmware fault or mismatch after replacement
High network load, improper termination, or short on the J1850 bus

Symptoms

Speedometer or odometer inoperative or erratic
Cruise control disabled or unavailable
Transmission shifting abnormalities or limp-home behavior
ABS, ESC, or traction control warnings/lights illuminated
Other modules report communication-related U-codes or loss of speed PID in live data

What to check

Read all stored and pending U‑codes and related freeze frame/PCM codes
Use a capable scan tool to view live vehicle speed PID and J1850/SCP bus messages
Check for additional ABS, instrument cluster, transmission, or network fault codes
Visually inspect wiring and connectors at ABS module, wheel speed sensors, instrument cluster, and central junctions for corrosion or damage
Verify battery voltage and engine/vehicle grounds (ABS, BCM, cluster) are within spec
Perform wiggle tests while monitoring the speed message for intermittent behavior

Signal parameters

Vehicle-speed SCP/J1850 message should be periodic (typically several Hz) and present when vehicle is rolling
Payload contains wheel-speed or computed vehicle-speed field (encoded per manufacturer; expected numeric range 0 = stopped to vehicle top speed)
Signal integrity: J1850 logic-level voltages and bus timing consistent with factory specification
Expected presence: message ID for vehicle-speed present on the SCP bus and not flagged as 'invalid' by receiving modules

Diagnostic algorithm

Connect a diagnostic tool capable of monitoring SCP/J1850 network traffic and read all modules
Confirm U1039 and note any accompanying codes (ABS, instrument cluster, PCM/TCM)
Check live-data: is vehicle speed PID present from any module? If absent, locate which module normally supplies speed data (often ABS/ESC module)
Visually inspect connectors/pins at ABS, wheel sensors, and instrument cluster; repair corrosion or damage
Backprobe the wheel-speed sensor circuit at a representative wheel to check sensor pulses while rotating the wheel (or road test with technician)
Verify power and ground at the transmitting module(s); repair any poor connections
If wheel-speed sensors show correct pulses but no vehicle-speed message appears on SCP, test ABS/module communication lines for continuity or shorts to battery/ground
Perform wiggle testing of wiring while watching the network message to find intermittent faults
If wiring and sensors are good, check for software updates or TSBs; reprogram or replace the module if it fails bench communication tests
Clear codes and test drive to confirm repair; monitor for reoccurrence

Likely causes

Faulty ABS/traction control module failing to transmit wheel-speed data
Open/short in the speed-sensor wiring harness or poor connector pins
Corroded or lost ground at ABS or instrument cluster
Missing or corrupted message due to a failed gateway or module update

Fault status

⚠️ Status

Invalid or missing SCP (J1850) vehicle speed data: the periodic vehicle-speed message is absent, corrupted, or not accepted by receiving modules.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1.5-3.0 hours

Similar codes

Repair manuals

Manual library for LAND ROVER

320

Browse 320 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.

LAND ROVER

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