OBDII Code List

U1040 CADILLAC - SCP Invalid or Missing Data for Vehicle Speed

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
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U1040 CADILLAC Possible Causes

  • Faulty / intermittent vehicle speed sensor / connections
  • J1850 / SCP Bus wiring intermittently open, shorted to power or ground
  • Faulty / intermittent connection at the Powertrain Control Module (PCM)

First diagnose U1040 CADILLAC code

    Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.

U1040 CADILLAC Tech Notes

This is typically an electrical wiring connection issue, either at the engine controller or at the sensors being monitored by the manufacturer.
It can occur if:
Wiring to the vehicle speed sensor breaks or the sensor itself has issues.

Cost of diagnosing the U1040 CADILLAC code

    Labor: 1.0

    The cost of diagnosing the U1040 CADILLAC code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle's make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.

When is the U1040 CADILLAC code detected?

When the PCM is unable to communicate with any other controller on the bus network at any time while the ignition switch is in the “Run” position.

U1040 CADILLAC Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)
  • O/D Light Flashes Continuously
  • Speedometer does not register

U1040 Cadillac Description

This is a manufacturer specific fault code and can be used for several different faults, depending upon what the manufacturer wants to use it for. The Powertrain Control Module (PCM) communicates over the Serial Communication Protocol (SCP) bus network, or J1850 bus. This is a medium-speed bus communication system and is fault tolerant, which means any type of intermittent/loose connection at these controllers will cause this code to set in memory, but will still operate, provided a data path is available. When the PCM is unable to communicate with any other controller at any time while the ignition switch is turned on, code U1040 will set. This is the typical reason for this code to set.
OBDII Code U1040 Cadillac - SCP Invalid or Missing Data for Vehicle Speed -

U1040 CADILLAC More Information

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