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 in the car that helps move the transmission fluid is getting too hot. It's like when your phone gets too hot and stops working well.
The control module for the electric or auxiliary transmission fluid pump is detecting an internal temperature that is higher than the set threshold.
The P0C1B code is triggered when the Powertrain Control Module (PCM) detects that the internal temperature of the Electric/Auxiliary Transmission Fluid Pump Control Module is too high. This can affect the performance of the transmission fluid pump, which is responsible for maintaining proper fluid pressure and flow in the transmission system.
• Illuminated Check Engine Light
• Transmission overheating warning
• Reduced transmission performance
• Faulty electric/auxiliary transmission fluid pump
• Poor electrical connections
• Overheating due to excessive load or environmental conditions
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for any signs of damage or corrosion.
• Check the transmission fluid level and condition.
• Repair or replace damaged wiring or connectors.
• Replace the electric/auxiliary transmission fluid pump if faulty.
• Ensure proper cooling and ventilation around the control module.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Toyota Prius
• Chevrolet Volt
• Ford Fusion Hybrid
• Regularly check and maintain transmission fluid levels.
• Ensure proper cooling system function.
• Avoid excessive loads that may overheat the transmission.
Transmission Control System
• Avoid driving the vehicle if the transmission is overheating.
• Have the vehicle inspected by a professional mechanic.
Check with your vehicle manufacturer for warranty coverage on transmission components.
This code has become more common with the increasing use of electric and hybrid vehicles, which often use electric pumps for transmission fluid.
High – Continued driving with this issue can lead to severe transmission damage.
Driving with a faulty transmission can be dangerous and may result in legal consequences if it leads to an accident.
• Vehicle should be at operating temperature.
• Ensure the transmission is in use.
The electric/auxiliary transmission fluid pump is usually located near the transmission assembly.
Q: Can I drive with a P0C1B code?
A: It's not recommended, as it can lead to further damage.
Q: How do I know if my transmission fluid pump is failing?
A: Symptoms include overheating warnings and reduced transmission performance.
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