AutoCodes – Generic – P0C74

P0C74 Code - Motor Electronics Coolant Pump 'B' Control Performance

Quick Answer

The inverter water pump assembly transmits rotation speed information to the power management control ECU (HV CPU). Common causes include Faulty Inverter cooling system, Inverter cooling system harness is open or shorted, Inverter cooling system circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0C74 indicates Motor Electronics Coolant Pump 'B' Control Performance.
Common causes: Common causes include Faulty Inverter cooling system, Inverter cooling system harness is open or shorted, Inverter cooling system circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 3,931

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Feb 13, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P0C74 Description

The inverter water pump assembly transmits rotation speed information to the power management control ECU (HV CPU). The power management control ECU (HV CPU) monitors the speed and detects malfunctions.

OBDII Code P0C74 - Motor Electronics Coolant Pump 'B' Control Performance - AutoCodes.com — P0C74 Code - Motor Electronics Coolant Pump 'B' Control Performance

What does this mean?

What are the Possible Causes of the DTC P0C74?

Faulty Inverter cooling system
Inverter cooling system harness is open or shorted
Inverter cooling system circuit poor electrical connection
Inverter water pump assembly
Power management control ECU

How to Fix the DTC P0C74?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0C74 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P0C74 code?

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Need Help with the Code?

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Information for Specific Makes

P0C74 Lexus — Motor Electronics Coolant Pump 'B' Control Performance
P0C74 Toyota — Motor Electronics Coolant Pump 'B' Control Performance

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.