P1702 - TRS Sensor Intermittent Circuit Malfunction
The P1702 code indicates an intermittent electrical fault in the Transmission Range Sensor (TRS) circuit, which monitors the gear selector position. This sensor provides critical input to the Powertrain Control Module (PCM) for shift logic, torque converter lockup, and reverse lights. An intermittent circuit malfunction means the signal is lost or erratic, often due to wiring issues, corrosion, or a failing sensor. This can cause incorrect gear engagement, harsh shifts, or no start condition.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Transmission stuck in limp mode or fails to shift properly
- Incorrect gear indication on dashboard
- Engine may not start or starts only in Park/Neutral intermittently
2. Most Common Causes
- Faulty transmission range sensor
- Damaged or corroded wiring/connectors in the TRS circuit
- Intermittent short or open in the sensor harness
- Poor ground connection
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data to confirm P1702 and check for related codes.
Step 2: Visually inspect the TRS connector and wiring for damage, corrosion, or loose pins.
Step 3: Test the TRS circuit continuity and resistance using a multimeter per manufacturer specs.
Step 4: If wiring is good, replace the transmission range sensor and clear codes.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. The transmission may shift erratically or get stuck in limp mode, which can cause unsafe driving conditions and potential transmission damage.
How much does it cost to fix?▼
Typically $50-$150 for parts and labor if it's just the sensor. Wiring repairs may add cost, but overall it's a relatively inexpensive fix.
5. Commonly Affected Makes
This is a manufacturer-specific code. The exact manufacturer is not confirmed in our current database.