Output Speed Sensor Intermittent Signal
The P0723 code indicates that the powertrain control module (PCM) has detected an intermittent or erratic signal from the output speed sensor, which monitors the rotational speed of the transmission output shaft. This sensor is critical for proper transmission shift timing, torque converter lockup, and speedometer operation. An intermittent signal can cause transmission shifting issues, incorrect speed readings, and may trigger limp mode.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Erratic or inaccurate speedometer readings
- Harsh or delayed transmission shifts
- Transmission stuck in limp mode or fails to shift
2. Most Common Causes
- Faulty output speed sensor
- Damaged or corroded wiring/connectors
- Metal debris or contamination on sensor tip
- Intermittent electrical connection due to vibration
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data to confirm P0723 and check for related codes.
Step 2: Visually inspect the output speed sensor and its wiring for damage, corrosion, or loose connections.
Step 3: Test sensor resistance and AC voltage output while rotating the output shaft; compare to manufacturer specs.
Step 4: Check for metal debris on the sensor tip and clean or replace as needed.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the transmission may shift erratically or enter limp mode, potentially causing further damage.
How much does it cost to fix?▼
Typically $50-$150 for parts and labor, depending on vehicle and shop rates.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.