Engine Speed Input Circuit Malfunction (P0725)
The P0725 code indicates a malfunction in the engine speed input circuit, which is responsible for sending the engine RPM signal from the crankshaft position sensor to the PCM. This signal is critical for transmission shift timing and torque converter lockup. A failure can cause erratic shifting, no shifting, or a no-start condition.
01. Most Common Causes
- Faulty crankshaft position sensor
- Wiring or connector issues in the sensor circuit
- Damaged reluctor ring or tone wheel
- PCM failure (rare)
02. Symptoms You Will Notice
- Check Engine Light on
- Transmission shifting problems (erratic, harsh, or no shift)
- Engine stalling or no-start
- Speedometer or tachometer malfunction
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Inspect crankshaft position sensor wiring and connector for damage or corrosion.
Step 3: Test sensor resistance and AC voltage output while cranking.
Step 4: Check reluctor ring for damage or debris.
Step 5: Verify PCM power and ground, and test signal circuit continuity.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, driving with P0725 can cause transmission damage or sudden stalling, leading to a safety hazard. Have it diagnosed immediately.
How much does it cost to fix?▼
Typically $50-$150 for a sensor replacement, but diagnostic fees and labor may add $100-$200.