MazicBay Diagnostics
MAZICBAYDiagnostics
FTC Reader Disclosure: When you purchase or register through links on our site, we may earn an affiliate commission at no extra cost to you. Read our Editorial & Advertising Policy.

U0073 on Chevrolet Colorado

Control Module Communication Bus A Off

Factory diagnostic protocol and troubleshooting wire for fault code U0073 specifically for the Chevrolet Colorado (2021–2026, 2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road).

Verified OEM Telemetry & Field Repair Tree
Chevrolet Colorado2021–2026
Chevrolet Colorado
Truck2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Colorado SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Not Recommended
Critical urgency level
Est. Repair Cost
$150 - $850 (DIY: $40 - $200)
Parts & Labor DIY
Check U0073 On Another Chevrolet Model:
Diagnose U0073 on Specific Colorado Model Year:

1. Symptoms of U0073 on Chevrolet Colorado

When the Engine Control Module (ECM/PCM) on your Chevrolet Colorado (2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road) logs fault code U0073, drivers commonly observe:

StabiliTrak / Traction / ABS / Engine warning lights lit on Chevrolet Colorado (2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road)
Transmission shifting harshly or refusing to shift out of 2nd gear on Chevrolet Colorado (2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road)
No communication with TCM, ABS, or BCM on Chevrolet Colorado (2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road)
Engine may refuse to crank on Chevrolet Colorado (2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road)
Chevrolet Colorado OBD-II Port Location
The 16-pin diagnostic connector is located Under driver side dashboard, left of center stack. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Chevrolet Colorado

Historical warranty claims and technical repair bulletins for Chevrolet Colorado point to the following failure distribution:

55%
Loose or corroded ground connection on transmission or frame (Chevrolet OEM Part)
25%
Faulty Transmission Control Module (TCM) or ABS module pulling bus down (Chevrolet OEM Part)
12%
Poor connection at large body-to-chassis pass-through harness connector (Chevrolet OEM Part)
8%
Aftermarket accessory (remote starter, GPS tracker, cheap OBD scanner) broadcasting invalid data (Chevrolet OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Chevrolet Colorado.

3. Step-by-Step DIY Repair Guide for Chevrolet Colorado

01
Unplug All Aftermarket OBD-II Devices

Remove any aftermarket insurance dongles, GPS trackers, or scan tools plugged into the DLC port. on the Chevrolet Colorado equipped with 2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road.

Required Tool: None
02
Inspect Frame and Transmission Ground Straps

Inspect braided ground straps on engine and transmission. Clean all contact surfaces to bare metal. on the Chevrolet Colorado equipped with 2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road.

Required Tool: Wire Brush, Sockets
03
Perform Full Vehicle Network Topology Scan

Scan all modules on vehicle. Note which modules are online and which are offline to pinpoint the break in the network daisy-chain. on the Chevrolet Colorado equipped with 2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road.

Required Tool: Full-System OBD-II Diagnostic Scanner
04
Check Terminating Resistance (60 Ohms)

Verify 60 ohms across Pins 6 and 14 with battery disconnected. on the Chevrolet Colorado equipped with 2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road.

Required Tool: Multimeter
05
Clear All System DTCs & Road Test

Clear DTCs from all modules and road test to verify error-free network transmission. on the Chevrolet Colorado equipped with 2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road.

Required Tool: Scan Tool
Recommended Parts & Testing Tools

Equipment for Diagnosing Chevrolet Colorado (U0073)

Prime Fast Delivery & Verified Fitment
Direct-Fit Replacement Part

Chevrolet Colorado OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Chevrolet Colorado.

$45 – $95 Prime
Check Fitment on Amazon
Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Chevrolet ColoradoVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
Find Parts on Amazon
* As an Amazon Associate, MazicBay earns from qualifying purchases. Prices & availability subject to change.

Other Common Fault Codes on Chevrolet Colorado

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Chevrolet Colorado:

4. Chevrolet Colorado U0073 FAQs

What causes code U0073 to trigger on a Chevrolet Colorado?

On the Chevrolet Colorado (2.7L Turbo 4-Cyl (310HP) / 3.6L V6 (308HP) / ZR2 AEV / Bison Off-Road), U0073 is most frequently caused by Loose or corroded ground connection on transmission or frame or Faulty Transmission Control Module (TCM) or ABS module pulling bus down.

Where is the OBD-II port located on my Chevrolet Colorado?

On the Chevrolet Colorado, the 16-pin DLC diagnostic connector is located Under driver side dashboard, left of center stack. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Chevrolet Colorado with code U0073?

No. Bus is shut down due to excessive transmission errors, leaving vehicle in unpredictable limp mode. Given that U0073 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.