The 07 Dodge Caliber is known for its Continuously Variable Transmission (CVT), which unfortunately, can experience overheating issues. One common problem is the transmission temperature sensor providing inaccurate readings, leading to the car entering “failsafe” mode and limiting performance. This article outlines a potential solution for addressing this issue by modifying the temperature sensor circuit.
Understanding the Problem: Inaccurate Temperature Readings
The root cause of the overheating issue often lies in a discrepancy between the actual transmission fluid temperature and the temperature reported by the sensor to the car’s computer. When the sensor reads higher than the actual temperature, the car’s computer can prematurely activate failsafe mode, even when the transmission fluid is within safe operating temperatures. This can result in reduced power and limited speed. A common symptom of this issue is the illumination of the transmission temperature warning light.
A Potential Solution: Modifying the Temperature Sensor Circuit
One potential solution involves adding a resistor to the temperature sensor circuit to adjust the signal sent to the car’s computer. By carefully selecting the resistor value, it’s possible to bring the reported temperature closer to the actual fluid temperature, preventing the premature activation of failsafe mode.
In one user’s experience with a 2007 Dodge Caliber CVT, a 150-ohm, 1/2-watt resistor was added to the circuit. This modification resulted in a more accurate temperature reading, allowing the vehicle to operate at highway speeds for extended periods without triggering the warning light or entering failsafe mode. Before the modification, the warning light would illuminate after approximately 20 miles of highway driving at 70 mph. After the modification, the vehicle could be driven for 40 miles at 75-80 mph without issue.
The temperature sensor circuit wire is typically a red wire with a white stripe, located in the round connector at the transmission. It’s important to note that cutting this wire completely will cause the computer to register an extremely low temperature (around -40 degrees). Therefore, adding a resistor is the preferred method.
Important Considerations and Disclaimer
This modification involves altering the vehicle’s electrical system and should only be attempted by individuals with experience in automotive electrical repair. Incorrectly modifying the circuit could potentially damage the transmission or other components. It’s crucial to measure the actual transmission fluid temperature using a reliable external thermometer and compare it to the reading from a diagnostic scanner to determine the appropriate resistor value.
Additionally, this modification may not address all potential causes of transmission overheating. Other factors, such as low fluid levels, worn clutches, or a faulty transmission cooler, could also contribute to overheating. A thorough diagnosis by a qualified mechanic is always recommended before attempting any repairs.
Throttle Calibration Issues
Some 07 Dodge Caliber owners have also reported issues with throttle calibration, particularly after the vehicle has reached operating temperature. This can manifest as hesitation or sluggish acceleration from a stop. A common temporary fix involves a throttle relearn procedure: turning the ignition on, pressing the gas pedal to the floor for 20 seconds, releasing the pedal for 20 seconds, and then turning the ignition off. In some cases, addressing the transmission temperature sensor issue has also resolved the throttle calibration problems.
Conclusion
Modifying the temperature sensor circuit with a resistor can be a potential solution for addressing inaccurate temperature readings in the 07 Dodge Caliber CVT. However, this modification should be performed with caution and only after careful diagnosis. Consulting a qualified mechanic is always recommended for any transmission-related issues.
