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 one of the car's computer parts isn't talking correctly with another part that helps control the pressure in the transmission. It's like when two friends are trying to play a game but their walkie-talkies aren't working right.
The P27AA code indicates that the data from the pressure control solenoid D is not matching the expected parameters set by the vehicle's computer system.
The pressure control solenoid D is responsible for regulating hydraulic pressure in the transmission. The vehicle's powertrain control module (PCM) monitors the data from this solenoid to ensure it is functioning correctly. If the data received is incompatible or outside the expected range, the PCM triggers the P27AA code.
• Transmission slipping
• Erratic shifting
• Illuminated check engine light
• Faulty pressure control solenoid D
• Wiring issues or poor electrical connections
• Faulty PCM or 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 connections to the solenoid.
• Test the solenoid's operation and resistance.
• Replace the faulty pressure control solenoid D.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM/TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular transmission maintenance
• Ensure proper electrical connections
• Avoid harsh driving conditions
Transmission Control Issue
• Avoid driving aggressively until the issue is resolved.
• Consult a professional mechanic for accurate diagnosis.
Check if the vehicle's powertrain warranty covers transmission components.
This code has been associated with transmission control issues in vehicles with electronic control systems.
Moderate – Addressing this issue soon can prevent further transmission damage.
Driving with a malfunctioning transmission can be unsafe and may lead to further damage.
• Vehicle at operating temperature
• Transmission in drive mode
The pressure control solenoid D is located within the transmission assembly.
Q: Can I drive with a P27AA code?
A: It's not recommended to drive with this code as it can cause further transmission damage.
Q: How do I clear the P27AA code?
A: The code can be cleared using an OBD-II scanner after the issue is resolved, but it may return if the problem persists.
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