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 the car shifts into 4th or 6th gear. It's like when you're riding a bike and the chain slips when you try to switch gears.
The transmission control module (TCM) has detected an incorrect gear ratio for either 4th or 6th gear, which means the actual gear ratio does not match the expected ratio.
When the TCM detects that the gear ratio for 4th or 6th gear is not as expected, it triggers the P188E code. This could be due to a mechanical failure in the transmission, a problem with the shift solenoids, or an issue with the transmission fluid.
• Check Engine Light is on
• Transmission slipping
• Poor acceleration or power loss
• Faulty shift solenoid
• Low or dirty transmission fluid
• Worn clutch or gears in the transmission
Transmission: A system in a car that transmits power from the engine to the wheels.
Shift Solenoid: An electromechanical device that controls the flow of transmission fluid.
• Check transmission fluid level and condition
• Inspect the wiring and connectors to the transmission
• Test the shift solenoids for proper operation
• Replace or repair faulty shift solenoid
• Change or flush transmission fluid
• Rebuild or replace the transmission if necessary
• OBD-II scanner
• Transmission fluid dipstick
• Multimeter
$200 - $2000 depending on the issue
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and change transmission fluid
• Avoid aggressive driving habits
• Perform regular transmission maintenance
Transmission Issue
• Drive gently to avoid further damage
• Have the vehicle inspected by a professional mechanic
Transmission issues may be covered under powertrain warranty, check with your manufacturer.
This code has been reported in vehicles with high mileage or those that have not had regular transmission maintenance.
Moderate – Should be addressed soon to prevent further damage.
Ignoring transmission issues can lead to unsafe driving conditions.
• Vehicle should be at operating temperature
• Test drive the vehicle to replicate the issue
The transmission is located beneath the vehicle, typically between the engine and the driveshaft.
Q: Can I drive with a P188E code?
A: It's not recommended to drive for long periods with this code, as it can lead to further damage.
Q: Will fixing the transmission fluid solve the P188E code?
A: If low or dirty fluid is the cause, then changing the fluid might solve the issue, but further diagnosis is recommended.
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