Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that a part in your car that helps change gears is getting too much power. It's like if you were trying to water a plant with a fire hose instead of a watering can.
The P099F code indicates that the power going to the shift solenoid H is higher than it should be, which can affect the transmission's ability to change gears smoothly.
The shift solenoid H is responsible for controlling the flow of transmission fluid within the valve body to engage the correct gear. A 'high' circuit condition suggests that the voltage or current in the circuit is above the expected range, which can be due to a short circuit or a faulty solenoid.
• Harsh or erratic shifting
• Transmission stuck in one gear
• Illuminated check engine light
• Short circuit in the wiring
• Faulty shift solenoid H
• Transmission control module (TCM) malfunction
Shift Solenoid: An electromechanical device that controls the flow of transmission fluid.
Transmission Control Module (TCM): A computer that controls the transmission's operations.
• Use an OBD-II scanner to confirm the code
• Inspect wiring and connectors for damage
• Test the shift solenoid H for proper function
• Repair or replace damaged wiring
• Replace faulty shift solenoid H
• Reprogram or replace the TCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 to $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid checks
• Routine maintenance of the transmission system
• Avoiding heavy towing beyond vehicle capacity
Transmission Control System Issue
• Do not ignore the check engine light; get the vehicle inspected.
• Avoid driving at high speeds until the issue is resolved.
Check if the vehicle's transmission warranty covers solenoid issues.
This code has been commonly reported in vehicles with over 100,000 miles and is often associated with transmission wear.
Moderate – Should be addressed soon to avoid further transmission damage.
Driving with a malfunctioning transmission can be unsafe and may lead to further mechanical issues.
• Vehicle at operating temperature
• Transmission in drive mode
The shift solenoid is located within the transmission valve body, which is typically accessible from the transmission pan.
Q: Can I drive with a P099F code?
A: It's not recommended to drive for long periods with this code, as it can lead to further transmission damage.
Q: How do I reset the P099F code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, the code should not return.
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