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 thinks there's a problem with how one of the clutches in the transmission is working. It's like when you try to squeeze a toy and it doesn't work right because you're not pressing hard enough.
The P2858 code indicates that the transmission control module (TCM) has detected an issue with the pressure or engagement performance of Clutch B within the transmission system.
The P2858 code is set when the TCM detects that the hydraulic pressure or engagement timing of Clutch B is below the expected range. This can affect the transmission's ability to shift gears properly, leading to performance issues.
• Check Engine Light is on
• Transmission slipping
• Poor acceleration
• Faulty clutch pressure control solenoid
• Low transmission fluid level
• Internal transmission mechanical failure
TCM: Transmission Control Module
Solenoid: An electromechanical device used to control fluid flow in the transmission
• Check transmission fluid level and condition
• Inspect wiring and connectors to the clutch pressure control solenoid
• Perform a transmission pressure test
• Replace the clutch pressure control solenoid
• Repair or replace damaged wiring or connectors
• Rebuild or replace the transmission if necessary
• OBD-II scanner
• Transmission pressure gauge
• Multimeter
$500 - $2500
Difficult
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regular transmission fluid changes
• Routine transmission inspections
• Avoid aggressive driving
Transmission Performance
• Avoid driving the vehicle until repaired
• Have the vehicle inspected by a professional mechanic
Check the vehicle's powertrain warranty for coverage on transmission components.
This code has been reported more frequently in vehicles with high mileage or those used in heavy-duty conditions.
High – This issue can lead to severe transmission damage if not addressed promptly.
Driving with a transmission issue can be unsafe and may lead to further vehicle damage.
• Vehicle at operating temperature
• Transmission in drive mode
Clutch B is located within the automatic transmission assembly.
Q: Can I drive my car with a P2858 code?
A: It's not recommended to drive with this code active, as it can cause further damage to the transmission.
Q: How do I know if my transmission fluid is low?
A: Check the transmission dipstick for fluid level and condition. The fluid should be at the correct level and not discolored or burnt.
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