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U00732019 Model Year TelemetryCritical Severity

U0073 on 2019 Toyota Prius

Control Module Communication Bus A Off

Technical troubleshooting wire for fault code U0073 specifically tailored for the 2019 Toyota Prius. Includes wiring sensor pinouts, freeze frame PID parameters, and step-by-step diagnostic tree.

2019 Engine Control Module (ECM) Specific Calibration
Toyota Prius2019 Prius
2019 Toyota Prius
EV2.0L 4-Cyl Hybrid (M20A-FXS 196HP) / Prius Prime PHEV (220HP)
2019 Stats
Vehicle
2019 Prius
2.0L 4-Cyl Hybrid (M20A-FXS 196HP) / Prius Prime PHEV (220HP)
ECU Subsystem
Automotive OBD-II
SAE Mode $01 & $02
Est. Repair Cost
$150 - $850 (DIY: $40 - $200)
OEM Parts & DIY
Urgency Level
Critical
Tow to Shop
Switch Prius Model Year for U0073

Common 2019 Prius Symptoms

  • StabiliTrak / Traction / ABS / Engine warning lights lit
  • Transmission shifting harshly or refusing to shift out of 2nd gear
  • No communication with TCM, ABS, or BCM
  • Engine may refuse to crank

Likely Root Causes on 2019 Prius

  • Loose or corroded ground connection on transmission or frame
  • Faulty Transmission Control Module (TCM) or ABS module pulling bus down
  • Poor connection at large body-to-chassis pass-through harness connector
  • Aftermarket accessory (remote starter, GPS tracker, cheap OBD scanner) broadcasting invalid data

Step-by-Step Fix Protocol for 2019 Toyota Prius

Step 1: Scan & Record Freeze Frame Data

Connect an OBD-II scanner to the DLC port under the driver dashboard. Record engine RPM, Short Term / Long Term Fuel Trim (STFT/LTFT), and engine coolant temperature at the moment U0073 set.

Step 2: Inspect Wiring Harness & Pin Voltages

Inspect the sensor connector on the 2019 Prius engine bay. Use a multimeter to verify reference voltage (5.0V / 12.0V) and ground continuity.

Step 3: Component Replacement & PCM Reset

Replace the verified defective component using OEM or equivalent grade parts. Clear DTC U0073 and complete an EPA drive cycle to verify readiness monitors set to READY.

Recommended Parts & Testing Tools

Equipment for Diagnosing 2019 Toyota Prius (U0073)

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Direct-Fit Replacement Part

2019 Toyota Prius OEM Replacement Sensor

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Direct-fit replacement assembly engineered to OEM tolerances for 2019 Toyota Prius.

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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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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 2019 Toyota PriusVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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