P0699

Symptoms

• Check Engine Light
• Inflated readings from group C sensors
• Unstable engine operation
• Multiple sensor error codes
• Malfunction of engine control systems

Causes

• Short circuit of reference line C to power line
• Faulty sensor with internal short to power
• Internal fault of the ECU reference voltage stabilizer
• Wiring damage
• Extraneous voltage in the sensor circuit of group C

How to Fix

1. Read all OBD-II codes and record the complete list
2. Measure the voltage on reference line C (norm: 5 V, tolerance ±0.2 V)
3. Identify all sensors of group C according to the electrical diagram
4. Turn off the sensors one by one and monitor the voltage change
5. Repair short to power or replace faulty sensor
6. If the external circuits are in good condition, replace the ECU

Related codes

Error P0699 by Vehicle Brand