Engine-Codes - Generic - U1100

U1100 - Invalid Or Missing Data For Primary Id

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

U1100 Possible Causes

  • Faulty Powertrain Control Module (PCM)
  • Powertrain Control Module (PCM) harness is open or shorted
  • Powertrain Control Module (PCM) circuit poor electrical connection

How is the U1100 code repair?

Start by checking 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 connector's pins.

What is the cost to diagnose the U1100 code

Labor: 1.0

The cost to diagnose the U1100 code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Engine cranks but may not start – may be intermittent
  • May or may not be able to communicate with a scan tool / depends on problem

U1100 Meaning

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. When a module receives a message for a critical operating parameter, the module records the identification number of the module which sent the message for State of Health monitoring. A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. When a module does not associate an identification number with at least one critical parameter within 5 seconds of beginning serial data communication, the Diagnostic Trouble Code (DTC) is set.

More Information

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