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 the car's computer is having trouble with the part that controls the hydraulic pump. It's like when a remote control doesn't work right with a toy car.
The P0946 code is triggered when the powertrain control module (PCM) detects a problem with the hydraulic pump relay or control circuit. This could mean the circuit is not working within the expected range.
The hydraulic pump relay is responsible for controlling the operation of the hydraulic pump, which is crucial for the transmission system. If there is an issue with the relay or the control circuit, such as a short or open circuit, the PCM will set the P0946 code.
• Transmission not shifting properly
• Warning light on the dashboard
• Possible decrease in fuel efficiency
• Faulty hydraulic pump relay
• Wiring issues in the control circuit
• Defective PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Check for any additional codes
• Inspect the wiring and connections to the hydraulic pump relay
• Test the hydraulic pump relay for proper operation
• Replace faulty hydraulic pump relay
• Repair or replace damaged wiring
• Reprogram or replace the PCM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $500
Moderate
• Honda Accord
• Toyota Camry
• Ford Fusion
• Regular maintenance checks
• Ensure proper electrical connections
• Avoid overloading the vehicle
Transmission Control System Issue
• Do not ignore the warning light
• Consult a professional mechanic
• Avoid driving under heavy loads until fixed
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has been associated with issues in vehicles with electronic transmission controls, particularly in models with complex hydraulic systems.
Moderate – It should be addressed soon to avoid transmission damage.
Driving with a malfunctioning transmission can lead to unsafe driving conditions. Always prioritize safety.
• Vehicle at operating temperature
• Transmission in drive mode
The hydraulic pump relay is usually located in the engine compartment fuse box or near the transmission.
Q: Can I drive with a P0946 code?
A: It's not recommended to drive for long periods with this code, as it can lead to transmission damage.
Q: How can I reset the P0946 code?
A: After fixing the issue, you can reset the code using an OBD-II scanner.
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