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U0073 on Cadillac CT5-V Blackwing

Control Module Communication Bus A Off

Factory diagnostic protocol and troubleshooting wire for fault code U0073 specifically for the Cadillac CT5-V Blackwing (2022–2026, 6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto)).

Verified OEM Telemetry & Field Repair Tree
Cadillac CT5-V Blackwing2022–2026
Cadillac CT5-V Blackwing
Sedan6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
CT5-V Blackwing 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 Cadillac Model:
Diagnose U0073 on Specific CT5-V Blackwing Model Year:

1. Symptoms of U0073 on Cadillac CT5-V Blackwing

When the Engine Control Module (ECM/PCM) on your Cadillac CT5-V Blackwing (6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto)) logs fault code U0073, drivers commonly observe:

StabiliTrak / Traction / ABS / Engine warning lights lit on Cadillac CT5-V Blackwing (6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto))
Transmission shifting harshly or refusing to shift out of 2nd gear on Cadillac CT5-V Blackwing (6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto))
No communication with TCM, ABS, or BCM on Cadillac CT5-V Blackwing (6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto))
Engine may refuse to crank on Cadillac CT5-V Blackwing (6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto))
Cadillac CT5-V Blackwing OBD-II Port Location
The 16-pin diagnostic connector is located Driver A-pillar base kick panel. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Cadillac CT5-V Blackwing

Historical warranty claims and technical repair bulletins for Cadillac CT5-V Blackwing point to the following failure distribution:

55%
Loose or corroded ground connection on transmission or frame (Cadillac OEM Part)
25%
Faulty Transmission Control Module (TCM) or ABS module pulling bus down (Cadillac OEM Part)
12%
Poor connection at large body-to-chassis pass-through harness connector (Cadillac OEM Part)
8%
Aftermarket accessory (remote starter, GPS tracker, cheap OBD scanner) broadcasting invalid data (Cadillac OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Cadillac CT5-V Blackwing.

3. Step-by-Step DIY Repair Guide for Cadillac CT5-V Blackwing

01
Unplug All Aftermarket OBD-II Devices

Remove any aftermarket insurance dongles, GPS trackers, or scan tools plugged into the DLC port. on the Cadillac CT5-V Blackwing equipped with 6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto).

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 Cadillac CT5-V Blackwing equipped with 6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto).

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 Cadillac CT5-V Blackwing equipped with 6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto).

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 Cadillac CT5-V Blackwing equipped with 6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto).

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 Cadillac CT5-V Blackwing equipped with 6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto).

Required Tool: Scan Tool
Recommended Parts & Testing Tools

Equipment for Diagnosing Cadillac CT5-V Blackwing (U0073)

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Direct-Fit Replacement Part

Cadillac CT5-V Blackwing OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Cadillac CT5-V Blackwing.

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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
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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 Cadillac CT5-V BlackwingVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Cadillac CT5-V Blackwing

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Cadillac CT5-V Blackwing:

4. Cadillac CT5-V Blackwing U0073 FAQs

What causes code U0073 to trigger on a Cadillac CT5-V Blackwing?

On the Cadillac CT5-V Blackwing (6.2L Handbuilt Supercharged LT4 V8 (668HP / 659 lb-ft / 6-Speed Manual / 10-Speed Auto)), 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 Cadillac CT5-V Blackwing?

On the Cadillac CT5-V Blackwing, the 16-pin DLC diagnostic connector is located Driver A-pillar base kick panel. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Cadillac CT5-V Blackwing 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.