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 of the car that helps move the transmission fluid is spinning too fast, kind of like a fan spinning too quickly.
The code indicates that the auxiliary transmission fluid pump B is operating at a speed higher than its intended range.
The P28ED code is triggered when the Engine Control Module (ECM) detects that the electric or auxiliary transmission fluid pump B is exceeding its specified speed threshold. This could be due to a malfunction in the pump itself or an issue with the control system that regulates its speed.
• Check Engine Light is on
• Unusual noise from the transmission area
• Transmission overheating or slipping
• Faulty transmission fluid pump B
• Electrical issues such as short circuits
• Faulty speed sensor or wiring problems
ECM: Engine Control Module, the computer that controls engine functions.
Transmission Fluid Pump: A component that circulates fluid within the transmission.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connections to the pump
• Test the pump's operation and speed sensor
• Replace the faulty transmission fluid pump B
• Repair or replace damaged wiring
• Replace the speed sensor if faulty
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance of the transmission system
• Ensure proper fluid levels
• Inspect electrical connections periodically
Transmission System Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving the vehicle until repaired
Check with the vehicle manufacturer for coverage related to powertrain components.
This code is relatively uncommon and typically associated with newer vehicles equipped with advanced transmission systems.
High – Continuing to drive with this issue can lead to transmission damage.
Ignoring this issue could lead to further damage and potential safety hazards while driving.
• Vehicle at operating temperature
• Transmission engaged in drive mode
The auxiliary transmission fluid pump B is typically located near the transmission housing.
Q: Can I drive with a P28ED code?
A: It's not recommended to drive with this code, as it can lead to further transmission damage.
Q: How is the pump speed monitored?
A: The pump speed is monitored by a speed sensor that sends data to the ECM.
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