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 noticed something unusual with the electric pump that helps move the transmission fluid. It's like when a pump in a fish tank isn't working right, and the water doesn't flow as it should.
The P1B18 code indicates a problem with the control of the electric or auxiliary transmission fluid pump. The pump is not operating as expected, leading to a deviation from the desired performance.
The electric or auxiliary transmission fluid pump is responsible for circulating transmission fluid, which is essential for cooling and lubricating the transmission components. The control deviation means the pump is not maintaining the expected flow or pressure, which can affect transmission performance.
• Transmission overheating
• Poor transmission performance
• Warning light on the dashboard
• Faulty transmission fluid pump
• Electrical issues such as wiring or connector problems
• Malfunctioning control module
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics and reporting in vehicles.
• Check for any other related trouble codes.
• Inspect the wiring and connectors to the pump.
• Test the operation of the transmission fluid pump.
• Replace the faulty transmission fluid pump.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$300 - $800
Moderate
• Chevrolet Volt
• Cadillac ELR
• Toyota Prius
• Regular maintenance and fluid checks
• Inspect wiring and connectors periodically
• Ensure proper cooling system function
Sensor Issue
• Avoid heavy driving until the issue is resolved.
• Consult a professional mechanic for diagnosis and repair.
Check with your vehicle manufacturer for specific warranty coverage related to transmission components.
This code has been reported in hybrid and electric vehicles where electric pumps are used for transmission fluid circulation.
Moderate – It is recommended to address this issue soon to prevent transmission damage.
Driving with a malfunctioning transmission pump can lead to further damage and potential safety issues.
• Engine running
• Transmission at operating temperature
The electric transmission fluid pump is typically located near the transmission or integrated within the transmission assembly.
Q: Can I drive with a P1B18 code?
A: It's not recommended to drive for long periods with this code active, as it can lead to transmission damage.
Q: How can I reset the P1B18 code?
A: After repairs, use an OBD-II scanner to clear the code. If the problem persists, the code will reappear.
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