P1589 Code - Throttle Control Unit Modulated Command Malfunction
Quick Answer
The Powertrain Control Module (PCM) tests the electronic throttle for the ability of the throttle plate to return to the default (limp home) position from both the open and closed positions. Common causes include Faulty Throttle Control Unit, Throttle Control Unit harness is open or shorted, Throttle Control Unit 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
- P1589 indicates Throttle Control Unit Modulated Command Malfunction.
- Common causes
- Common causes include Faulty Throttle Control Unit, Throttle Control Unit harness is open or shorted, Throttle Control Unit 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 P1589 Description
What are the Possible Causes of the DTC P1589?
- Faulty Throttle Control Unit
- Throttle Control Unit harness is open or shorted
- Throttle Control Unit circuit poor electrical connection
How to Fix the DTC P1589?
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 P1589 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 P1589 code?
Need more information on how to fix the P1589 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P1589 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- P1589 Ford — Throttle Control Unit Unable To Control Desired Throttle Angle
- P1589 Honda — Motor Power Inverter Module Current Signal Circuit Problem
- P1589 Toyota — Acceleration Sensor Learning Value
Frequently Asked Questions about P1589 Code
1. What are the common symptoms of OBDII code P1589 (Throttle Control Unit Modulated Command Malfunction)?
The common symptoms include engine stalling, rough idling, poor acceleration, and the check engine light being illuminated.
2. What are the possible causes of OBDII code P1589?
Possible causes of this code include a faulty throttle control unit, wiring issues, sensor malfunctions, or problems with the engine control module.
3. How serious is OBDII code P1589?
This code can cause drivability issues and potentially lead to unsafe driving conditions. It is recommended to address this issue promptly to avoid further damage to the vehicle.
4. How can I diagnose OBDII code P1589?
Diagnosing this code typically involves using an OBDII scanner to retrieve the code and then conducting further testing to pinpoint the exact cause, which may require professional diagnostic equipment.
5. Can I continue driving with OBDII code P1589?
It is not recommended to continue driving with this code present, as it can lead to further damage to the vehicle and potentially unsafe driving conditions.
6. How can OBDII code P1589 be repaired?
Repairing this code often involves inspecting and repairing the throttle control unit, checking and repairing any wiring issues, replacing faulty sensors, or reprogramming the engine control module.
7. Will resetting the check engine light resolve OBDII code P1589?
Resetting the check engine light may temporarily turn it off, but it will not fix the underlying issue causing the code. It is important to diagnose and repair the problem to prevent the code from reappearing.
8. Can a DIYer fix OBDII code P1589?
Depending on the cause of the code, some DIYers may be able to address the issue themselves, such as checking and cleaning connections. However, more complex repairs may require professional assistance.
9. How much does it cost to repair OBDII code P1589?
The cost of repairing this code varies depending on the specific cause and the labor rates in your area. It is recommended to obtain quotes from multiple mechanics to compare prices.
10. Is OBDII code P1589 a common issue in certain car models?
This code may be more common in certain car models that have a history of throttle control unit or sensor issues. It is advisable to check with your vehicle's manufacturer or online forums for specific model-related information.
Discuss the causes and fixes for P1589 OBDII Code
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replaced the evr valve as well as replace the car vacuum control switch solenoid. the code is gone, cycle drive for 15 miles or so and it went to 1 inc and 7 ready mode. passed the state inspection afterwards, this is for my 2002 Mazda Protege5
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