Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is making the car shift gears to cool down because the engine is getting too hot.
The engine control module (ECM) detects that the engine oil or coolant temperature is too high, and it forces an upshift in the transmission to help reduce engine load and temperature.
P1248 is triggered when the ECM senses that either the engine oil or coolant temperature exceeds a predefined threshold. To protect the engine from overheating, the ECM commands the transmission to upshift, reducing engine RPM and load, thereby helping to lower the temperature.
• Engine overheating
• Transmission shifting at unusual times
• Check engine light illuminated
• Low engine coolant level
• Faulty thermostat
• Malfunctioning engine oil cooler
ECM: Engine Control Module
RPM: Revolutions Per Minute
• Check engine coolant and oil levels.
• Inspect the thermostat for proper operation.
• Examine the engine oil cooler for blockages or leaks.
• Refill engine coolant to the proper level.
• Replace faulty thermostat.
• Repair or replace the engine oil cooler if necessary.
• OBD-II scanner
• Coolant system pressure tester
• Thermometer
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain coolant levels.
• Schedule routine maintenance for the cooling system.
• Inspect hoses and belts for wear and tear.
Engine Performance
• Avoid driving aggressively when the engine is hot.
• Ensure regular maintenance checks are performed.
Check with your vehicle manufacturer; cooling system components may be covered under the powertrain warranty.
This code typically appears in vehicles with high mileage or those that have not been maintained regularly.
High – Continuing to drive with this code can lead to severe engine damage.
Ignoring engine overheating can lead to engine failure, which is both a safety hazard and can result in costly repairs.
• Engine at operating temperature
• Vehicle driven under normal conditions
The thermostat is typically located near the engine block connected to the radiator via a hose.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to severe engine damage due to overheating.
Q: Can I drive my car with a P1248 code?
A: It's not recommended to drive with this code as it indicates the engine is overheating, which can cause damage.
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Fitment Required · Vehicle-fitment part
Relevant when coolant-temperature and warm-up faults indicate a thermostat-related issue.
Coolant-temperature and warm-up faults often lead to thermostat testing and replacement.
Thermostats are vehicle-specific and should be matched by engine and housing style.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.