Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with one of the parts in the car's transmission that helps it change gears. It's like if a switch isn't working right, so the car can't shift gears smoothly.
The P099D code is triggered when the powertrain control module (PCM) detects a problem with the electrical circuit controlling the shift solenoid H. This solenoid is responsible for managing the flow of transmission fluid to change gears.
The shift solenoid H is part of the automatic transmission system. It is an electrically controlled valve that directs transmission fluid to change gears. The PCM monitors the solenoid's performance and range, and if it detects a deviation from expected parameters, it sets the P099D code.
• Transmission slipping
• Harsh or delayed shifting
• Illuminated check engine light
• Faulty shift solenoid H
• Wiring issues in the shift solenoid circuit
• Malfunctioning transmission control module (TCM)
PCM: Powertrain Control Module
TCM: Transmission Control Module
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the shift solenoid H for proper operation.
• Replace the faulty shift solenoid H.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid changes
• Routine inspection of transmission wiring
• Avoiding aggressive driving habits
Transmission Control Issue
• Have a professional diagnose the issue.
• Avoid driving the vehicle until the problem is fixed to prevent further damage.
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with issues in vehicles with high mileage or those that have not had regular transmission maintenance.
Moderate – It is recommended to address this issue soon to prevent further damage to the transmission.
Driving with a faulty transmission can lead to unsafe driving conditions. Address the issue promptly.
• Vehicle at operating temperature
• Transmission in drive mode
The shift solenoid is located inside the transmission, usually accessible by removing the transmission pan.
Q: Can I drive with a P099D code?
A: It's not recommended to drive with this code, as it can lead to further transmission damage.
Q: How do I reset the P099D 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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