P0599 BMW Code - Thermostat Heater Control Circuit High
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
- P0599 BMW indicates Thermostat Heater Control Circuit High.
- 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.
Code P0599 BMW Description
What are the Possible Causes of the DTC P0599 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 P0599 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 P0599 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.
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Frequently Asked Questions about P0599 BMW Code
1. What does the OBDII code P0599 mean on a BMW?
The P0599 code indicates a problem with the thermostat heater control circuit, specifically that the circuit is registering a high voltage condition.
2. What are the common symptoms of a P0599 code on a BMW?
Symptoms may include the check engine light turning on, engine overheating or running cooler than normal, reduced fuel efficiency, and poor heater performance.
3. What causes the P0599 code to appear in a BMW?
Common causes include a faulty thermostat, damaged thermostat heater control wiring, corroded electrical connectors, or a malfunctioning engine control module (ECM).
4. Can I continue driving my BMW with a P0599 code?
While it may be safe to drive for short distances, ignoring this code can lead to engine overheating or inefficient operation, potentially causing further damage.
5. How is the P0599 code diagnosed on a BMW?
A mechanic will typically use a scan tool to confirm the code, visually inspect wiring and connectors, and test the thermostat heater circuit and related components for proper function.
6. What repairs are needed to fix the P0599 code on a BMW?
Repairs may include replacing the thermostat, repairing or replacing damaged wiring or connectors, or in rare cases, reprogramming or replacing the engine control module.
7. Is the thermostat the only component that can cause the P0599 code?
No, other issues like short circuits, open circuits, or problems within the ECM can also trigger this code.
8. How much does it cost to repair a P0599 code on a BMW?
The cost can vary depending on the specific issue, but replacing the thermostat typically costs between $150 and $400, including parts and labor.
9. Can a P0599 code affect my BMW’s fuel efficiency?
Yes, a malfunctioning thermostat can cause the engine to run at incorrect temperatures, leading to reduced fuel efficiency.
10. How can I prevent the P0599 code from recurring on my BMW?
Regular maintenance, including inspecting wiring and connectors and ensuring the cooling system is in good condition, can help prevent this code from returning.
Discuss the causes and fixes for P0599 BMW OBDII Code
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Fyi I fix the small thermosat and I am leaking from the expansion tank
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You need to find out where the leak is coming from and replaced or repair the part. If for example the leak comes from a radiator hose, then replaced the hose and clear the code
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How did you fix the thermostat?
If the leak comes from the expansion tank, then you need to repair or replaced the tank.
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had to fix this but in order for a shop to fix it they had to buy a part from bmw so it was like $399 or 400$
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