AutoCodesBMW – P0598 BMW

P0598 BMW Code - Thermostat Heater Control Circuit Low

Quick Answer

The Engine Control Module (ECM) controls the Pulse Width Modulated (PWM) thermostat. Common causes include Failed Engine Cooling Thermostat, Engine Cooling Thermostat harness is open or shorted, Engine Cooling Thermostat 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
P0598 BMW indicates Thermostat Heater Control Circuit Low.
Common causes
Common causes include Failed Engine Cooling Thermostat, Engine Cooling Thermostat harness is open or shorted, Engine Cooling Thermostat 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.
AI answers can be wrong. Verify repairs with testing. Open full chat
Code Popularity 23,058
How popular is this code, among other codes? Low
Table of contents Created and updated by William Orellana on May 27, 2024
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Code P0598 BMW Description

The Engine Control Module (ECM) controls the Pulse Width Modulated (PWM) thermostat. The engine coolant thermostat heater controls coolant flow and regulates the engine operating temperature. The ECM supplies 12 V to the thermostat. The ECM controls the engine coolant thermostat heater by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage.
OBDII Code P0598 BMW - Thermostat Heater Control Circuit Low - AutoCodes.com
P0598 BMW Code - Thermostat Heater Control Circuit Low

What are the Possible Causes of the DTC P0598 BMW?

  • Failed Engine Cooling Thermostat
  • Engine Cooling Thermostat harness is open or shorted
  • Engine Cooling Thermostat circuit poor electrical connection

How to Fix the DTC P0598 BMW?

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.

Code Tech Notes

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0598 BMW 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 P0598 BMW code?

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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.

Frequently Asked Questions about P0598 BMW Code

1. What does the OBDII code P0598 mean on a BMW?

P0598 indicates a "Thermostat Heater Control Circuit Low," meaning there is an issue with the thermostat heater circuit receiving insufficient voltage.

2. What are the common symptoms of a P0598 code in a BMW?

Symptoms may include an illuminated check engine light, poor engine warm-up, reduced fuel efficiency, and irregular engine temperature readings.

3. What causes the P0598 code to appear on a BMW?

Common causes include a faulty thermostat heater, damaged wiring or connectors in the circuit, a blown fuse, or a malfunctioning engine control module (ECM).

4. Can I drive my BMW with a P0598 code?

While the car may still be drivable, ignoring the code can lead to engine performance issues, poor fuel economy, and potential overheating or underheating problems.

5. How do I diagnose the P0598 code on my BMW?

Start by inspecting the thermostat heater wiring and connectors for damage, check the corresponding fuse, and use a multimeter to test for proper voltage at the thermostat heater.

6. What is the cost to fix a BMW with a P0598 code?

Repair costs vary but typically range from $100 to $300, depending on whether the thermostat heater, wiring, or other components need replacement.

7. Can a faulty thermostat itself cause the P0598 code?

Yes, a malfunctioning thermostat or its internal heater can trigger this code due to its inability to regulate engine temperature properly.

8. How do I reset the P0598 code after repairs on a BMW?

You can reset the code using an OBDII scanner. However, ensure the issue is fully resolved before clearing the code to prevent it from returning.

9. What tools are needed to troubleshoot the P0598 code on a BMW?

You’ll need an OBDII scanner, a multimeter for electrical testing, and basic hand tools to inspect and repair wiring or replace the thermostat.

10. Could a P0598 code lead to engine damage if not addressed?

Yes, prolonged engine temperature irregularities caused by this issue can eventually lead to overheating or other engine-related problems.

Discuss the causes and fixes for P0598 BMW OBDII Code

  • Changed thermostat. What's next

  • What model and year is your BMW? Did you use a factory thermostat? Some aftermarket thermostats do not meet the factory specifications and could trigger the code.

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