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U0073LexusLexus ES HubAll Lexus U0073Critical Severity

U0073 on Lexus ES

Control Module Communication Bus A Off

Factory diagnostic protocol and troubleshooting wire for fault code U0073 specifically for the Lexus ES (2020–2026, 3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD).

Verified OEM Telemetry & Field Repair Tree
Lexus ES2020–2026
Lexus ES
Sedan3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
ES 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 Lexus Model:
Diagnose U0073 on Specific ES Model Year:

1. Symptoms of U0073 on Lexus ES

When the Engine Control Module (ECM/PCM) on your Lexus ES (3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD) logs fault code U0073, drivers commonly observe:

StabiliTrak / Traction / ABS / Engine warning lights lit on Lexus ES (3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD)
Transmission shifting harshly or refusing to shift out of 2nd gear on Lexus ES (3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD)
No communication with TCM, ABS, or BCM on Lexus ES (3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD)
Engine may refuse to crank on Lexus ES (3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD)
Lexus ES OBD-II Port Location
The 16-pin diagnostic connector is located Directly under driver dash, left side of steering column. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Lexus ES

Historical warranty claims and technical repair bulletins for Lexus ES point to the following failure distribution:

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

3. Step-by-Step DIY Repair Guide for Lexus ES

01
Unplug All Aftermarket OBD-II Devices

Remove any aftermarket insurance dongles, GPS trackers, or scan tools plugged into the DLC port. on the Lexus ES equipped with 3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD.

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 Lexus ES equipped with 3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD.

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 Lexus ES equipped with 3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD.

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 Lexus ES equipped with 3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD.

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 Lexus ES equipped with 3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD.

Required Tool: Scan Tool
Recommended Parts & Testing Tools

Equipment for Diagnosing Lexus ES (U0073)

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Direct-Fit Replacement Part

Lexus ES OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Lexus ES.

$45 – $95 Prime
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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 Lexus ESVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Lexus ES

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Lexus ES:

4. Lexus ES U0073 FAQs

What causes code U0073 to trigger on a Lexus ES?

On the Lexus ES (3.5L V6 (2GR-FKS 302HP) / 2.5L Hybrid (ES 300h 215HP) / 2.5L AWD), 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 Lexus ES?

On the Lexus ES, the 16-pin DLC diagnostic connector is located Directly under driver dash, left side of steering column. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Lexus ES 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.