P0694: Fan 2 Control Circuit High Voltage
The P0694 code indicates that the Powertrain Control Module (PCM) has detected a high voltage condition in the control circuit for the cooling fan 2. This typically means the circuit voltage is above the expected range, often due to a short to power, a faulty fan relay, or a damaged wiring harness. The PCM monitors the fan control circuit for proper voltage levels; when it sees excessive voltage, it sets this code. This can cause the fan to run continuously or not operate correctly, leading to potential overheating issues.
1. Most Common Causes
- Short to power in the fan 2 control circuit
- Faulty cooling fan relay (fan 2)
- Damaged wiring or connector in the fan circuit
- Faulty PCM (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine overheating or higher than normal operating temperature
- Cooling fan running continuously or not at all
- Reduced air conditioning performance
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to verify the code and check for related codes (e.g., P0691-P0694).
Step 2: Visually inspect the fan 2 wiring and connector for damage, corrosion, or shorts to power.
Step 3: Test the fan 2 relay and control circuit voltage with a multimeter; compare to manufacturer specs.
Step 4: If wiring and relay are okay, test the fan motor itself for proper operation and resistance.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code, as it can lead to engine overheating and potential damage. Have the issue diagnosed and repaired promptly.
How much does it cost to fix?▼
The typical repair cost ranges from $50 to $150, depending on the cause. Replacing a relay or repairing wiring is usually inexpensive, but if the PCM is faulty, costs can be higher.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.