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U01152021 Model Year TelemetryCritical Severity

U0115 on 2021 Acura RDX

Lost Communication with ECM/PCM B

Technical troubleshooting wire for fault code U0115 specifically tailored for the 2021 Acura RDX. Includes wiring sensor pinouts, freeze frame PID parameters, and step-by-step diagnostic tree.

2021 Engine Control Module (ECM) Specific Calibration
Acura RDX2021 RDX
2021 Acura RDX
SUV2.0L VTEC Turbo (272HP / 280 lb-ft / SH-AWD)
2021 Stats
Vehicle
2021 RDX
2.0L VTEC Turbo (272HP / 280 lb-ft / SH-AWD)
ECU Subsystem
Automotive OBD-II
SAE Mode $01 & $02
Est. Repair Cost
$150 - $800
OEM Parts & DIY
Urgency Level
Critical
Tow to Shop
Switch RDX Model Year for U0115

Common 2021 RDX Symptoms

  • Multiple warning lights
  • Limp mode
  • No start

Likely Root Causes on 2021 RDX

  • CAN bus wire short/open
  • Blown ECM fuse
  • Faulty secondary ECM/PCM

Step-by-Step Fix Protocol for 2021 Acura RDX

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 U0115 set.

Step 2: Inspect Wiring Harness & Pin Voltages

Inspect the sensor connector on the 2021 RDX 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 U0115 and complete an EPA drive cycle to verify readiness monitors set to READY.

Recommended Parts & Testing Tools

Equipment for Diagnosing 2021 Acura RDX (U0115)

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Direct-Fit Replacement Part

2021 Acura RDX OEM Replacement Sensor

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Direct-fit replacement assembly engineered to OEM tolerances for 2021 Acura RDX.

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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.

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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.

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