Transmission Park Position Sensor Circuit Low
The P07B3 code indicates that the transmission control module (TCM) has detected a low voltage condition in the park position sensor circuit. This sensor tells the TCM when the transmission is in park, enabling the engine to start and the key to be removed. A low circuit voltage can be caused by a faulty sensor, damaged wiring, or a poor electrical connection. This issue can prevent the vehicle from starting or cause incorrect gear position readings.
01. Most Common Causes
- Faulty park position sensor
- Damaged or corroded wiring/connectors in the sensor circuit
- Short to ground in the sensor circuit
- Faulty transmission control module (TCM)
02. Symptoms You Will Notice
- Engine may not start or start only in neutral
- Transmission stuck in park or unable to shift out of park
- Check Engine Light illuminated
- Incorrect gear position display on dashboard
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for other related codes.
Step 2: Visually inspect the park position sensor and its wiring for damage, corrosion, or loose connections.
Step 3: Test the sensor's voltage and ground signals using a multimeter; compare with manufacturer specifications.
Step 4: If sensor and wiring are okay, test the TCM for proper operation or perform a sensor replacement.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The vehicle may not start or could unexpectedly shift out of park, posing a safety risk. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
Typically between $50 and $150 for parts and labor, depending on whether the sensor or wiring needs replacement.