AutoCodes – GMC – U1073 GMC

U1073 GMC Code - Invalid Or Missing Data For Engine Coolant

Quick Answer

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Common causes include Faulty Engine Coolant Sensor, Engine Coolant Sensor harness is open or shorted, Engine Coolant Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: U1073 GMC indicates Invalid Or Missing Data For Engine Coolant.
Common causes: Common causes include Faulty Engine Coolant Sensor, Engine Coolant Sensor harness is open or shorted, Engine Coolant Sensor circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 633

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 22, 2020

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code U1073 GMC Description

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 the state of health monitoring/node alive messages. A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. Once an identification number is learned by a module, it will monitor for that module node alive message. Each module on the class 2 serial data circuit is required to send a Node Alive message every 2 seconds. When no message is detected from a learned identification number for 5 seconds, a Diagnostic Trouble Code (DTC) U1073 is set.

OBDII Code U1073 GMC - Invalid Or Missing Data For Engine Coolant - AutoCodes.com — U1073 GMC Code - Invalid Or Missing Data For Engine Coolant

What does this mean?

What are the Possible Causes of the DTC U1073 GMC?

Faulty Engine Coolant Sensor
Engine Coolant Sensor harness is open or shorted
Engine Coolant Sensor circuit poor electrical connection

How to Fix the DTC U1073 GMC?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What does this mean?

Code 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:
Someone changes a battery while the ignition switch is left on, that is, left in the RUN position.
Someone flashes/upgrades their engine controller - other modules unable to communicate with PCM during this process - this will set U1073 at a multitude of controllers on the vehicle - all false codes. Erase and carry on.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the U1073 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about U1073 GMC Code

1. What are the common symptoms of OBDII code U1073 GMC?

- Common symptoms include engine overheating, erratic temperature gauge readings, poor fuel efficiency, and possible engine stalling.

2. What are the possible causes of OBDII code U1073 GMC?

- The code can be triggered by issues such as a faulty engine coolant temperature sensor, damaged wiring or connectors, low coolant levels, or a malfunctioning engine control module (ECM).

3. How can I diagnose the cause of OBDII code U1073 GMC?

- Diagnose the code by checking the coolant level, inspecting the temperature sensor and its connections, testing the ECM, and scanning for any other related codes to pinpoint the issue.

4. Can I continue driving with OBDII code U1073 GMC active?

- It is not recommended to drive with this code active, as it can lead to engine damage or overheating. It's best to address the underlying issue promptly.

5. What are some repair tips for resolving OBDII code U1073 GMC?

- Repair tips include checking and topping up coolant levels, testing and replacing the coolant temperature sensor, repairing any damaged wiring, and resetting the ECM after repairs.

6. How much does it typically cost to fix OBDII code U1073 GMC?

- The cost of fixing this code can vary depending on the underlying issue. Repairs may range from a simple sensor replacement (around $50-$200) to more complex wiring or ECM repairs ($200-$500+).

7. Can a DIY enthusiast fix OBDII code U1073 GMC themselves?

- Depending on their skill level, DIY enthusiasts can attempt to fix this code by following repair guides, using diagnostic tools, and performing basic checks. However, more complex issues may require professional help.

8. Are there any preventive measures to avoid OBDII code U1073 GMC in the future?

- Regularly check coolant levels, inspect the cooling system for leaks or damage, perform routine maintenance on the temperature sensor, and address any warning signs promptly to prevent this code from reoccurring.

9. Will resetting the OBDII code U1073 GMC make it go away permanently?

- Resetting the code may temporarily clear the error, but if the underlying issue is not addressed, it is likely to trigger the code again. It's crucial to diagnose and repair the root cause for a permanent fix.

10. Is OBDII code U1073 GMC specific to GMC vehicles only?

- While the code designation may mention GMC, OBDII code U1073 related to engine coolant issues can be found in various vehicle makes and models, not exclusive to GMC vehicles.