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 the part of the car that controls the hydraulic pump, which helps the car change gears. It's like when a light switch is stuck on, and the light won't turn off.
The P0948 code indicates that the powertrain control module (PCM) has detected a high voltage condition in the hydraulic pump relay or control circuit.
The hydraulic pump relay is responsible for supplying power to the hydraulic pump, which is used in automatic transmissions to control gear shifts. A 'high' condition means the voltage is above the expected range, which could indicate a short circuit or a faulty relay.
• Transmission not shifting properly
• Check Engine Light illuminated
• Vehicle may enter limp mode
• Faulty hydraulic pump relay
• Short circuit in the control circuit
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Inspect the hydraulic pump relay for damage or corrosion.
• Check the wiring and connectors for signs of wear or shorts.
• Test the relay with a multimeter to ensure it is functioning correctly.
• Replace the hydraulic pump relay if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• Multimeter
• OBD-II scanner
• Relay tester
$100 - $300
Moderate
• Honda Accord
• Toyota Camry
• Ford F-150
• Regularly inspect electrical connections for corrosion.
• Ensure proper maintenance of the transmission system.
• Avoid overloading the vehicle.
Transmission Control Issue
• Do not ignore the Check Engine Light.
• Avoid driving the vehicle if it is not shifting properly.
• Seek professional diagnosis and repair.
Check your vehicle's warranty for coverage on transmission components.
This code has been associated with vehicles that have a history of electrical issues in the transmission system.
Moderate – Address the issue soon to avoid further transmission damage.
Driving with a malfunctioning transmission can be dangerous and may lead to further damage.
• Vehicle in park with engine running
• Transmission at operating temperature
The hydraulic pump relay is typically located in the engine compartment fuse box.
Q: Can I drive with a P0948 code?
A: It's not recommended to drive with this code as it can lead to transmission damage.
Q: How do I clear a P0948 code?
A: After repairs, you can clear the code using an OBD-II scanner.
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